scientific research paper reddit

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

• View all journals
• Explore content
• About the journal
• Publish with us
• Sign up for alerts
• CAREER FEATURE
• 01 April 2024

How scientists are making the most of Reddit

• Hannah Docter-Loeb 0

Hannah Docter-Loeb is a freelance writer in Washington DC.

You can also search for this author in PubMed   Google Scholar

It has been almost 18 months since Elon Musk purchased Twitter, now known as X. Since the tech mogul took ownership, in October 2022, the number of daily active users of the platform’s mobile app has fallen by around 15%, and in April 2023 the company cut its workforce by 80%. Thousands of scientists are reducing the time they spend on the platform ( Nature 613 , 19–21; 2023 ). Some have gravitated towards newer social-media alternatives, such as Mastodon and Bluesky. But others are finding a home on a system that pre-dates Twitter: Reddit.

Access options

Access Nature and 54 other Nature Portfolio journals

Get Nature+, our best-value online-access subscription

24,99 € / 30 days

cancel any time

Subscribe to this journal

Receive 51 print issues and online access

185,98 € per year

only 3,65 € per issue

Rent or buy this article

Prices vary by article type

Prices may be subject to local taxes which are calculated during checkout

Nature 628 , 221-223 (2024)

doi: https://doi.org/10.1038/d41586-024-00906-y

Fiesler, C., Zimmer, M., Proferes, N., Gilbert, S. & Jones, N. Proc. ACM Hum. Comp. Interact. 8 , 5 (2024).

Article   Google Scholar  

Proferes, N., Jones, N., Gilbert, S., Fiesler, C. & Zimmer, M. Soc. Media Soc . https://doi.org/10.1177/20563051211019004 (2021).

Download references

Related Articles

• Information technology

How religious scientists balance work and faith

Career Feature 20 MAY 24

How to set up your new lab space

Career Column 20 MAY 24

I’m worried I’ve been contacted by a predatory publisher — how do I find out?

Career Feature 15 MAY 24

How I fled bombed Aleppo to continue my career in science

Career Feature 08 MAY 24

The dream of electronic newspapers becomes a reality — in 1974

News & Views 07 MAY 24

A global timekeeping problem postponed by global warming

Article 27 MAR 24

AI image generators often give racist and sexist results: can they be fixed?

News Feature 19 MAR 24

Senior Postdoctoral Research Fellow

Senior Postdoctoral Research Fellow required to lead exciting projects in Cancer Cell Cycle Biology and Cancer Epigenetics.

Melbourne University, Melbourne (AU)

University of Melbourne & Peter MacCallum Cancer Centre

Overseas Talent, Embarking on a New Journey Together at Tianjin University

We cordially invite outstanding young individuals from overseas to apply for the Excellent Young Scientists Fund Program (Overseas).

Tianjin, China

Tianjin University (TJU)

Chair Professor Positions in the School of Pharmaceutical Science and Technology

SPST seeks top Faculty scholars in Pharmaceutical Sciences.

Chair Professor Positions in the School of Precision Instruments and Optoelectronic Engineering

We are committed to accomplishing the mission of achieving a world-top-class engineering school.

Chair Professor Positions in the School of Mechanical Engineering

Aims to cultivate top talents, train a top-ranking faculty team, construct first-class disciplines and foster a favorable academic environment.

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Quick links

• Explore articles by subject
• Guide to authors
• Editorial policies

Reddit's r/science community is one of science writing's biggest outlets, with the stats to prove it

At ASHG 2019, Jennifer (Piper) Below shares the numbers behind r/science's global reach

Farah Qaiser

Molecular Genetics

University of Toronto

By Kon Karampelas on Unsplash  

When scientists look to sharing their newly published research, they often turn to media outlets with large audiences. But at the American Society of Human Genetics ( ASHG) 2019 conference in October, I realized that Reddit's r/science community is the front page we may all be missing out on.

In case you haven't already stumbled on to the site, Reddit – “read and edit” – is a news aggregation social media platform which is often referred to as the front page of the internet. It's composed of over a million subreddits (communities), where the 13-year-old r/science is “a place to share and discuss new scientific research." Fun fact: r/science has over 22.6 million subscribers, making it the fifth largest subreddit on the site.

Jennifer (Piper) Below is an Assistant Professor of at Vanderbilt University Medical Center – and is also one of the 1,500+ moderators on Reddit's r/science community. At ASHG’s communications workshop, Below shared that in September 2019 alone, the r/science community “averaged 5.6 million unique users and 29 million page views” – which happens to be a larger circulation than all top ten US newspapers' weekday circulation (including USA Today, The New York Times, and the Wall Street Journal).

At r/science, Below says that there are three goals: to normalize interactions with scientists, to illuminate the processes of science (rather than only the results) and to promote disintermediation (i.e. skipping news outlets to go straight to the scientists). Below says that r/science does this in three ways: user-submitted links to research, hosting a monthly science discussion series (replacing the old Ask-Me-Anything format) and by verifying users.

As per Below, in September 2019 alone, the r/science community “averaged 5.6 million unique users and 29 million page views” – which happens to be a larger circulation than all top ten US newspapers' weekday circulation (including USA Today, The New York Times, and the Wall Street Journal).

By AbsolutVision on Unsplash  

Below says that “presenting your work in an r/science discussion is likely the largest audience you will ever have in your career” and hopes that science discussions on Reddit will become a culturally expected next step for scientists once they publish an “important” paper. For example, r/science has hosted discussion series on climate change , concussion injuries right after the 2019 Super Bowl and a conversation with the research group of Frances Arnold – the 2018 Nobel Prize in Chemistry winner , where the climate change science discussion had around ten million impressions and over 183k views.

Submissions requirements and comment rules help keep r/science conversations polite and scientific. In fact, by verifying their expertise and displaying an educational flair (e.g. “Grad Student | Physics”), Below says that Reddit users can help provide the context behind research, including methodology and statistics. Of r/science's 5,000+ verified users, 31% have a Bachelor of Science degree, where an additional 4% and 24% identify as professors and graduate students. Biology (19%) is the largest verified field, followed closely by engineering (16%) and medicine (12%). Journalists, writers and university press relations can also request flairs.

Interested in exploring r/science? Below recommends creating a Reddit account – and to consider adding an educational flair to your account or hosting a discussion series. After all, if you truly want to communicate your science with the public, why not head directly to the front page of the internet?

• Facebook Share
• Twitter Tweet

• Email Email

Get new Lab Notes sent to your inbox

Submit your own Lab Note

Share an interesting science story or tell a short one of your own

A newly discovered cryosphere-dwelling yeast stays alive by making ethanol

Rhodotorula frigidialcoholis was isolated from 150,000-year-old permafrost in the McMurdo Dry Valleys of Antarctica

Mitra Kashani

Microbial Ecology

Centers for Disease Control and Prevention

Photo by USGS on Unsplash

Most of the Earth’s biosphere is permanently cold and contains environments below 0° C,  known as the cryosphere. Microorganisms like bacteria and fungi call the cryosphere home, despite the seemingly inhospitable conditions. Some can even stick around in the ice for thousands of years .

To make this happen, microorganisms have evolved adaptations that help them survive their forever winter – whether it’s because they prefer cold environments (known as psychrophiles) or they can tolerate them (psychrotolerants) until more favorable conditions arise.

One example of cryosphere adapted fungi are a genus of single celled, pink pigmented yeast called Rhodotorula , which have been isolated and characterized from a range of cold ecosystems. In order to survive the coldest and driest parts of the Earth, they’ve evolved unique strategies to handle the elements. In a recent study by scientists at McGill University, a novel species of Rhodotorula yeast is changing our understanding of fungal cold adaptations in new and unexpected ways.

The newly identified psychrotolerant yeast, Rhodotorula frigidialcoholis, was isolated from 150,000-year-old ice cemented permafrost in the McMurdo Dry Valleys of Antarctica. The researchers found it has two novel responses to extreme cold temperatures: it can switch its metabolism from respiration to ethanol fermentation as its main pathway, and can overexpress molecules called small non-coding RNAs (sRNAs) that help regulate which genes are expressed after transcription. R. frigidialcoholis now also holds the record for the lowest temperature reported for ethanol production by any microorganism.

Scientists are still working to understand the precise role of sRNA expression in cold adaptation, but the metabolic switch from respiration to ethanol fermentation by R. frigidialcoholis may help the novel yeast – and potentially others like it – save energy, slowing down the freezing point in their cells as a long-term survival strategy.

El sur de Inglaterra alberga a una pequeña, pero prospera población de walabíes de cuello rojo

Los walabíes fueron introducidos al país al principio del siglo XX

Maria Gatta

Ecology and Conservation Biology

University of the Witwatersrand, Johannesburg

Image by  pen_ash  from  Pixabay  

Walabíes: son muy monos, relativamente pequeños, y para los europeos, tienen una apariencia inédita. Esto es lo que llevó a la introducción del walabí de cuello rojo, una especie australiana, a principios del siglo XX a países como Inglaterra, Irlanda, y Francia. En aquellos tiempos, los walabíes se mantenían en zoos y colecciones privadas. Algunos escaparon , sobre todo durante la segunda guerra mundial, cuando la gente tenía cosas más importantes por las que preocuparse por mantener vallas.

Hoy en día, hay muy poca información disponible sobre que les pasó a aquellos walabíes introducidos. Dos científicos, Holly English y Anthony Caravaggi , decidieron investigar qué pasó con aquellos animales. Recogieron información sobre avistamientos de walabíes en los registros oficiales, las redes sociales, y los periódicos. Gracias a lo monos e inusuales que son, los avistamientos suelen ser mencionados en los periódicos locales.

En su artículo reciente publicado en la revista científica Ecologia y Evolución , los investigadores encontraron pequeñas poblaciones de walabíes viviendo a lo largo del sur de Inglaterra. Aunque alguno de estos animales es probablemente un fugitivo moderno de una colección privada o un zoo, es improbable que tales escapadas sean el origen de todos los avistamientos de la región. Por ello, los investigadores creen que las poblaciones del sur de Inglaterra se están reproduciendo en libertad.

Así que, si alguna vez estas en el sur de Inglaterra y crees que has visto a un walabí, ¡no te sorprendas demasiado!

Research demonstrates speech-in-noise training helps children with auditory processing disorder

Children with APD have difficulty perceiving speech when there is background noise and may have trouble on cognitive tests

Stephanie Santo

Photo by MI PHAM on Unsplash

Central auditory processing disorder (APD), a hearing disability, can impact cognitive functioning and academic performance in those who experience it. It is typically diagnosed in childhood. Children with APD have difficulty perceiving speech when there is background noise, called speech-in-noise perception, and may have trouble on cognitive tests.

Previous studies on the link between cognitive performance, background noise, and auditory processing in children have included participants without confirmed APD diagnoses. Therefore, researchers in a recent study examining the potential utility of a technique called speech-in-noise training selected participants with confirmed diagnoses to understand the relationship between APD, speech-in-noise perception, and working memory.

The researchers administered one cognitive and five auditory processing tests to the participants. They gave the children lists of words and asked them to repeat the words back. In one of the tests, the words were audible only in one ear and the participants were asked to repeat the words regardless of which ear they heard it from. 

Participants in the experimental group were given speech-in-noise training within a week of the evaluation. During this type of training , participants are asked to listen for words or speech presented with background noise, which gets progressively louder or more difficult to navigate as the training progresses. The goal is to help people pick out important words while filtering out background sounds.

The study found a link between how participants did on auditory tests and their performance on cognitive tests. Speech-in-noise training generally improved the participants' results on both tests. This study confirms that speech-in-noise training may be a helpful intervention for children with APD diagnoses.

Deep sea bacteria use selfishness to their advantage

Some bathypelagic bacteria have found a way to maximize their energy intake by taking food into their cells before breaking it down

Sarah Brown

Marine Science

University of North Carolina - Chapel Hill

Photo by Cristian Palmer on Unsplash

The bathypelagic zone of the ocean, which spans depths between 1,000 and 4,000 meters (3,300 – 13,100 feet) below the ocean’s surface, is characterized by permanent darkness, low temperatures, and high pressure. In this hostile environment, slow-growing bacteria survive by relying on sinking organic matter , including proteins and carbohydrates called polysaccharides, from algae in the sun-lit surface waters of the ocean. 

Much of this organic matter is heavily degraded by the time it reaches the deep sea, and intact polysaccharides are hard to come by. For bacteria living in the bathypelagic zone, survival means getting the most out of every rare polysaccharide that reaches these depths – and a new study suggests that for some bacteria, selfishness may be key to their survival.

Bacteria typically feed by releasing enzymes into the water to break down their food into small enough pieces to be taken into the cell. However, by releasing these enzymes into the surrounding water, bacteria naturally lose some of the products of this process. While breaking down food externally can be profitable when resources are in high abundance , it is a much less successful strategy in environments where resource availability is low, such as the deep sea.

In a recent pre-print that I am a co-author on, we suggest that some bacteria at these depths may be using a selfish method of polysaccharide uptake. This method allows them to bring large pieces of polysaccharides into their cells without first breaking them down externally, enabling the bacteria to selfishly keep all the food to themselves.

To make this discovery, we incubated bathypelagic bacteria with fluorescently-labeled polysaccharides. By staining the bacteria with a DNA-binding dye and viewing them under microscopes, we were able to see intact pieces of polysaccharides inside the cells, indicating that these bacteria had not used external enzymes to break them down prior to uptake.

These results provide the first example of selfish behavior in deep-sea bacteria, suggesting that selfishness may be more common among bacteria than previously thought.

The screen you are reading this on is probably emitting volatile organic compounds

A new study demonstrates that, in addition to a variety of other household products, LCD screens also emit these compounds

Kay McCallum

Atmospheric Chemistry

McMaster University

Photo by Jorge Ramirez on Unsplash

We spend a lot of time indoors - so it’s important that we know what’s in indoor air. Indoor chemists are especially concerned with volatile organic compounds (VOCs, a class of molecules that includes benzene, formaldehyde, and more), which can be harmful to human health and are highly reactive.

VOCs are released into indoor air from a number of sources –  plants , wall paint , cooking and cleaning – and, as a recent study by a pair of researchers at the University of Toronto shows, from LCS screens like those in your phone, TV, and laptop.

To measure how LCD screens affect air quality, the researchers collected data on what types of compounds were contained in two types of samples: one of regular indoor air, and one collected near the surface of on an LCD screen like a new TV or an old laptop. They identified the chemical signatures of those compounds using a technique called proton-transfer reaction mass spectrometry. They then cross-referenced these signatures against lists of known liquid crystal monomers (the “building blocks” of LCD screens) and other compounds used in LCD screen manufacturing.

They found over 30 VOCs and 10 L liquid crystal monomers were heavily emitted into the air exposed to the screen, including extremely reactive species like isoprene and acetic acid. This finding indicates that LCD screens are an important source of VOCs in indoor environments, and that our screen-time may be exposing us to more than just new things on the internet.

Getting vaccinated against COVID-19 improves mental health

People who received the COVID-19 vaccine experienced less depression and anxiety compared to unvaccinated individuals

Danielle Llaneza

Health and Medicine

Hunter College and MD Anderson Cancer Center

Photo by Erin Aguis on Unsplash

Vaccine hesitancy remains a pressing issue during the COVID-19 pandemic. About 69 percent of people in the US who are 12 years or older have received the full vaccine dosage, thus protecting them from COVID-19. Yet, a portion of the remaining population remains reluctant to get the vaccine. This group's decision is based on their concern about the vaccine's safety, lack of belief in the danger posed by COVID-19, and distrust for the government. Some also face logistical difficulties in getting vaccinated, either because they live in rural areas or do not have the ability to take sick days from work if they experience side effects. 

A promising new study , published by researchers at the University of Southern California, found that individuals had significant decreases in mental health distress after receiving the first dose of the vaccine. This knowledge can, hopefully, push some vaccine hesitant people to receive their shots.

The researchers surveyed 8000+ people to measure their depressive and anxiety symptoms (mental distress level) before and after their first vaccine dose. They found that vaccinated individuals reported less mental distress after receiving the first dosage, while the unvaccinated group retained a consistently high level of mental distress for the entire 1-year study period.

Receiving the vaccine has turned from a health to a political affair as the remaining population voluntarily refuses to get vaccinated. This voluntary refusal puts themselves, the community, and individuals who cannot get vaccinated (like children under five years old and immunocompromised individuals) at greater risk of being infected with COVID-19. At this point, severe reactions to COVID-19 are preventable but will remain a significant problem until all eligible persons are vaccinated. This study shows that we have an opportunity to increase our physical and mental wellbeing. We must invest in more substantial policy at the corporate, state, and federal levels to increase vaccination rates now.

Don't bank those seeds — some oaks can be "cryopreserved"

Acorns can't be frozen, but tips of oak tree shoots can

Christina Del Greco

Genetics and Genomics

University of Michigan

Hao Zhang / Unsplash

Due largely in part to human-induced climate change, up to 40 percent of all species of plants are at risk of extinction. In response, conservationists have developed seed banks , where seeds of at-risk plants are frozen and stored in case of emergency.

Many species of oak trees fall on the list of endangered plants. However, their acorns are not usable after freezing, so conservationists are unable to add them to seed banks . As a result, scientists have had to investigate alternative preservation methods for oaks.

A recently published study has demonstrated that, for oaks, an alternative to seed-banking could be shoot tip cryopreservation . Shoot tip cryopreservation is the process of clipping off the shoot tip of a plant — the part that contains cells able to regenerate into a whole new plant — and placing it in droplets of a freezable substance. The plants are then frozen in liquid nitrogen, -320 degrees Fahrenheit, until they're ready to be thawed and grown.

Scientists found that, when they attempted shoot tip cryopreservation on four different species of oaks, some the plants were able to grow after freezing and unfreezing. But some didn't survive. Survival depended on the species. One species survived liquid nitrogen freezing 56 percent of the time, another never did. When looking specifically at the most successful species, the researchers also found that slight temperature differences in the freezing and unfreezing processes can have an effect on both general plant survival and exactly how well the plants recover after freezing.

Up until now, there had been no evidence that shoot tip cryopreservation worked on oaks. While survival does depend on the species of oak, this study demonstrates that this method can be added to the arsenal of the different conservation tools available for oak preservation, and can hopefully contribute to finding methods that work for all oak species.

Male and female mice form memories of fearful events differently

A drug that blocks memory forming in male mice has a different effect in females

Evolutionary Biology

Polytechnic Institute of Setúbal

Memory is the process of encoding, storing and retrieving information by the brain. Several studies indicate that fear memories are processed differently in male and female animals, but the basis of these differences are still mostly unknown. A study published in Nature Communications has brought new information to the table: a drug known to reduce the ability to remember fearful events in male mice turns out to to increase that ability in females.

The team that led the research is from the Institut de Neurociències at the Universitat Autònoma de Barcelona. They study the mechanisms of the memory of fear, aiming to find treatments for pathologies associated with the experience of traumatic events. This project coupled behavioral studies of mice with hormonal and biochemical and molecular analysis.

The drug they used in the study, osanetant (which is not used to treat humans), blocks a pathway for brain signaling that is involved in creating lasting memories of fear. The researchers found that the drug's blocking action has opposite effects on males and females, and that it is dependent on sexual hormones — testosterone in males and estradiol in females.

While the new results about sexual differences and memory are very interesting on their own, they raise an important issue for experimental design. Most research studies are done in males. But scientists would benefit from understanding how drugs affect more than just males. That's particularly relevant in this field in particular, given that fear related disorders are more common in women.

Psilocybin reduced depression symptoms as much as a leading antidepressant

New research compared the "magic mushrooms" component to Lexapro

Soren Emerson

Neuroscience

Vanderbilt University

Photo by Önder Örtel on Unsplash

Since their introduction in the late 1980s , selective-serotonin reuptake inhibitors (SSRIs) have become the go-to treatment for major depression. SSRIs, however, have a number of limitations: they take several weeks to start working, can cause a variety of side-effects , and do not help some people with depression. A series of recent clinical investigations suggest that psilocybin, the active compound in magic mushrooms, may be an effective alternative. One question that these studies left unanswered, however, is how effective psilocybin treatment is compared to SSRIs.

In a first-of-its-kind study recently published in The New England Journal of Medicine , researchers at the Center for Psychedelic Research at Imperial College London compared psilocybin and escitalopram, an SSRI drug sold under the name Lexapro, as treatments for major depression. The six-week long study enrolled 59 volunteers with moderate-to-severe major depression. They were randomly and blindly assigned to receive treatment with psilocybin and an escitalopram control, or escitalopram and a psilocybin control. All the participants also received psychological support.

To evaluate the two treatments, the researchers compared the change from baseline on the 16-item Quick Inventory of Depressive Symptomatology–Self-Report (QIDS-SR-16), a basic clinical measure of depression symptoms. Based on results of the QIDS-SR-16, psilocybin and escitalopram both reduce depression symptoms. The researchers did not detect a statistically significant difference between the two treatments.

The results of other measures taken in the study, however, suggest that psilocybin may be more effective than escitalopram. When designing the study, the researchers determined that the QIDS-SR-16 most directly addressed their experimental question and would therefore be the primary outcome measure, but they also evaluated depression symptoms with a number of additional scales. Nearly all secondary outcome measures favored psilocybin over escitalopram, but their results hold less weight than the QIDS-SR-16 because of how the study was designed.

The study was also limited by its small size, non-random enrollment of interested volunteers, and the possibility that participants may have been unblinded by the strong subjective effects of psilocybin or the well-known side-effects of SSRIs. Nonetheless, as the most rigorous evaluation of the therapeutic potential of psilocybin conducted to date, the results provide a benchmark for the design of future investigations.

Cocaine use slices and dices RNA in mouse brain cells

The analysis of epigenetic changes caused by cocaine use adds to the evidence that substance use disorders are rooted in biology

Anna Rogers

Molecular Biology

UC Berkeley

Photo by Omar Flores on Unsplash

Neuroscientists are known for doing some strange things to mice in their pursuit of learning about the brain. One such strange thing is training mice to self-administer cocaine, but it’s all for a good cause: Self-administration can help us understand the biological underpinnings of substance use disorders.

In a study recently published in Neuron , researchers found that cocaine use changes the DNA in mouse brains, specifically in the brain regions associated with reward. After consuming cocaine, the DNA in their brain cells had different chemical modifications known as epigenetic changes. These epigenetic changes also altered the types of RNAs the cells made through splicing. In this process, pieces of genes are left out or added in to create different RNAs that create different proteins.

Scientists have known RNA splicing is particularly important for neurons, and the researchers behind this mouse study saw many epigenetic and splicing changes after the mice consumed cocaine. Then, they artificially recreated one specific epigenetic change at a gene called Srsf11 . This led Srsf11 to be spliced differently. However, Srsf11 is also a gene that controls splicing across the genome, meaning that changes to it had ripple effects in the mice. This one change also altered splicing across a few hundred other genes, some of which were previously implicated in substance use disorders. Most interestingly, the mice with the modified version of Srsf11 self-administered more cocaine, showing that these sorts of changes in the brain may underlie addiction.

Some researchers argue that increasing the body of evidence for the biological basis of substance use disorders reduces stigma against people who use substances, though the effectiveness of this in public messaging is debated . Regardless, though we continue to see evidence that substance use disorders are biologically-driven, there are currently no approved drugs to treat the overuse of cocaine . Epigenetics and RNA splicing may be promising targets for future medical interventions.

Your gut bacteria may be hoarding your medication

Researchers have observed this effect in petri dishes and nematodes

Madeline Barron

Microbiology

Photo by Towfiqu barbhuiya on Unsplash

When we take medications, we generally do two things:  first, we swallow some pills, then we wait for them to kick in. Whether or not they do, however, may be tied to our gut microbes.

Intestinal bacteria influence the availability and activity of therapeutic drugs in the body. For instance, some bacteria metabolically convert, or ‘ biotransform ,’ drugs into their active forms; others inactivate them. And some, according to a new report published in Nature, don’t chemically manipulate drug molecules — they hoard them.

In this study, researchers incubated 25 representative strains of gut bacteria with 12 orally administered drugs, including those used to treat asthma, high cholesterol, and diarrhea. By measuring drug levels in the growth medium before and after 48 hours of incubation, the scientists identified 29 novel bacteria-drug pairs in which the drug was depleted from the medium. Comparing drug concentrations in the medium alone with that of the total culture revealed that, in most cases, the drug was absent from the medium but recoverable from the total culture. These results suggest the medications were accumulating inside the bacteria.

The question is: When bacteria vacuum up drug molecules, does this alter the drug’s effect on the host?

To explore this, the researchers incubated Caenorhabditis elegans , a nematode and model organism, with duloxetine, an antidepressant that was accumulated by several bacterial strains. While duloxetine alone decreased nematode motility, adding a duloxetine-accumulating strain of E. coli to the culture reduced this effect.

These findings indicate that bacterial hoarding of medications may affect the way those drugs affect their targets. Ultimately, more research is required to determine whether a similar scenario plays out in the human gut, and in the context of other drugs. Greater insight into the interplay between medications and gut microbes could expand our understanding of drug bioavailability and efficacy, and how they may vary from one person (and gut microbiome) to the next.

Meet the springhare: the first glow-in-the-dark African mammal known to science

Researchers discovered the springhare's fluorescent abilities entirely by accident

Shakira Browne

University College Dublin

Olson et al 2021 under CC BY 4.0

Fluorescence is caused by an animal absorbing light and bouncing it back out again, and in nature, it’s not a new thing. Fluorescence occurs across only a handful of mammals but they span three different continents and inhabit entirely different ecosystems. The platypus is one such animal, whose glow-in-the-dark abilities were only discovered in 2020. 

But, a discovery earlier this year by Northland College researchers that springhares fluoresce is special: it is the first documented case of biofluorescence in an Afro-Eurasian placental mammal. The study purports that perhaps fluorescence in mammals is not as rare as once previously thought. 

The researchers entered Chicago’s Field Museum of Natural History armed with a flashlight, with the goal of examining the fluorescent abilities of flying squirrels. Along the way, they accidentally discovered that springhares also glow. One specimen they examined was collected in 1905, and continued to glow in the dark for over 100 years.

The researchers subsequently tested live springhares (this time, in the dead of night—springhares are nocturnal) and found they could also fluoresce, predictably stronger than in the dead specimens. This study raises the questions: What other animals are out there, pulsating in every different shade of the rainbow after the clock strikes midnight? 

For the first time ever, researchers have "housebroken" cows

Controlling where cow waste ends up could lead to cleaner air and water and decreased greenhouse gas emissions

Fernanda Ruiz Fadel

Animal Behavior and Behavioral Genetics

Advanced Identification Methods GmbH

Photo by Lomig on Unsplash

In a strange triumph of science, researchers have now successfully potty trained 11 cows . The study, done by research groups in Germany and New Zealand, included 16 calves, which they trained by giving the calves a reward when they urinated in a latrine and later by adding an unpleasant stimulus (three-second water spray) when they began urinating outside of the designated area. The calves' potty training performances are equivalent to those of children and better than very young children.

But why is this important?

First, because cattle waste is a substantial contributor to greenhouse gas emissions and soil and water contamination. Being able to collect cow waste in one place would enable us to treat and dispose of it properly. One way of doing it is by keeping the animals confined in barns, but that lowers their welfare conditions.

Second, it shows that cows are able to react to and control their reflexes, indicating that their behavior — like shown with many other animal species before — is subject to modification by using rewards. This demonstrates that cows have more awareness than previously thought, which is important to better understand their wellbeing and welfare needs. Having cattle keep their own living areas a bit cleaner would also increase their welfare.

Potty training cows in farm settings is time consuming and logistically challenging, but it would help significantly decrease gas emissions without compromising animal welfare. Model calculations predict that capturing 80 percent of cattle waste could lead to a 56 percent reduction in ammonia emissions, which would lead to cleaner air for all of us.

Feeding extra amino acids to cells with a mutated enzyme makes them grow faster

This new finding could lead to advances in treatment of diseases caused by ARS mutations

Photo by David Clode on Unsplash

Our cells require proteins, which are composed of individual amino acids connected in a long chain, to perform important functions. These amino acids are delivered to protein-building machinery by another molecule called a tRNA . Amino acids and tRNAs are attached together, or charged, by an enzyme colloquially known as ARS .

Mutations in ARS enzymes cause diseases such as Charcot-Marie-Tooth disease, which affects the nerves to a person's arms and legs, because cells cannot make proteins properly. Currently, there are few treatments for ARS defects. However, researchers predict that flooding cells with extra amino acid might allow defective ARS enzymes to function better.

To test this, scientists identified patients with ARS mutations that cause charging defects, and grew their cells in a petri dish. They then treated these cells with different amounts of amino acid, and compared the electrical impedance of the cells that received treatment to those that did not. “Impedance analysis” is an approach where scientists put cells on a surface that can conduct electricity.  As cells grow, they block the electrical current, and the speed at which the current is blocked corresponds to how fast the cells are growing. 

The scientists found cells with ARS mutations that were treated with amino acids grew faster than cells that did not receive treatment. These promising results meant that the researchers could move on to trying this treatment in the patients themselves. They designed specific amino acid treatments for four people with the same ARS mutations they studied in cells, monitored their symptoms over time, and found that giving patients amino acids alleviated many of their most severe symptoms.

While we still don’t know if these results are applicable to all patients with ARS mutations, this study found a potential new way to treat ARS mutations in patients. Considering that ARS mutations can cause very severe disease, this is exciting and promising for both scientists and patients alike.

White pine blister rust's habitat range is changing with the climate

New study in Sequoia and Kings Canyon National Parks demonstrates the complexity of changing plant-pathogen interactions

Population Genetics

New York University

Marek Argent on Wikimedia Commons (CC BY-SA 3.0) 

A rapidly changing climate is expected to shift where species live . This will also alter human activities like agriculture and forest conservation , as the ranges of plant pathogens change. 

Scientists have been predicted that climate change will both increase and decrease the prevalence of a pathogen across its geographic range, depending on local climate effects, a pathogen’s favored conditions, and host factors. In an article published in Nature Communications , a group of researchers led by Joan Dudney demonstrate exactly this in a natural system. 

The researchers report the effects of climate change on the occurrence of white pine blister rust in the Sequoia and Kings Canyon National Parks (SEKI) in California. Blister rust is a fungal disease that threatens white pine forests across Europe and North America. Leveraging blister rust prevalence data from two surveys conducted twenty years apart (1996 and 2016) in SEKI, alongside climate data over the same timeframe, they authors found that a warming, increasingly dry climate caused contraction of blister rust's range at low elevations and expansion at higher elevations, where conditions remained relatively mild. They noted an approximately 33 percent decline in overall disease prevalence despite these expansions and high elevations.

The blister rust fungus has a complex lifecycle that requires both a white pine tree and an alternative host, such as Ribes shrubs. Dudney and her fellow researchers found that alternative hosts were less common at higher elevations, likely limiting blister rust's ability to infect pine trees at those elevations even though the pathogen could live there. They also observed that aridity, or dryness, played an important role in determining infection risk.

The study provides a roadmap for future studies on host-pathogen-climate interactions. Genomic adaptations of rapidly reproducing pathogens to changing conditions could further alter these dynamics and represent an additional avenue to explore in future work.

These uses of poop for protection are stranger than fiction

Defense by dung doesn't always elicit disgust in predators to repel them

Simon Spichak

Judy Gallagher via Flickr (CC BY 2.0)

To some animals, their own excretion isn't just waste. They may use their fecal matter to ward off predators. Here are several examples of fecal prowess.

Poop... ink? 

Sperm whales are some of the largest animals to ever exist, reaching a whopping 14 meters long in adulthood. Despite their intimidating size, they still can get spooked (such as by pesky divers) and unleash a poopy trick. Through emergency defecation, a sperm whale can disperse a smoke screen of shit into the water before the cetacean makes its escape. Waving its tail to disperse their poop creates an underwater "poopnado," as Canadian diver Keri Wilk called it. These enormous diarrhea clouds also help recycle nutrients and store immense amounts of carbon, mitigating some effects of climate change.

Shields — I mean poop — up! 

The larvae of the tortoise beetle are the Captain America of the animal kingdom — because they make shields out of poop. Using their maneuverable anus that sits on their flexible rear end, they deposit their dung defense on their back. The fecal armor, made in part from the larvae's shed exoskeleton, can double as a club to whack off potential predators.

Some beetle species can swing their poop shields around to hit predators with them. (And some of the poop is shed exoskeleton, in order to retain any toxins that the beetle may have.) pic.twitter.com/E5MVDjlCHT — Dr. Stephanie (@punkrockscience) September 3, 2021

Rancid repellent

The Green Woodhoopoe takes a rather straightforward approach to defense. Young birds will simply coat themselves in liquid poop, using the odor to deter — or gross out — would-be predators. You wouldn't want to eat a poop-slathered bird now, would you?

Distance and our eyes distort the true colors of stars

New research calculates the colors of stars based on their actual energy distributions

Briley Lewis

Astronomy and Astrophysics

University of California, Los Angeles

Hubble / NASA, ESA, and the Hubble SM4 ERO Team

From our perspective on Earth, most stars look like tiny, twinkling dots. But what color would a star be if you could actually see it up close?

Most astronomy textbooks will clearly say hot stars are blue, and colder stars are red. These colors come from an idealized version of the light a star gives off, called a blackbody curve . That’s not quite the whole story though, especially for smaller stars — the outer layers of a star absorb parts of the light emitted from the center, and our eyes respond differently to different wavelengths of light.

New research published in Research Notes of the American Astronomical Society calculated colors of stars based on their actual energy distributions and the response of the human eye. Turns out, we’ve been missing stars’ true colors. The hottest stars appear blue, as we’ve thought, but stars like our Sun appear off-white. Smaller stars, like K and M stars , are beige instead of red.

Most shocking of all — brown dwarfs aren’t even brown, they’re violet! These cool sub-stars are purple because absorption by molecules in their atmospheres takes out a whole chunk of their visible light, leaving only red and blue light for us to see.

There are a few more complexities that could change the color a star appears to us. For example, clouds on brown dwarfs may change how their atmosphere absorbs light, and that’s something researchers are still trying to figure out. Earth’s atmosphere reddens light, too, so all these colors would look different if we were looking from Earth’s surface. For now, though, it’s fun to have a better idea of what vivid colors are out in the universe, including purple (brown) dwarfs!

Zebrafish without "love hormone" neurons show no desire to socialize with each other

New research shows the importance of oxytocin for social affiliation and isolation

Kareem Clark

Virginia Polytechnic Institute and State University

Whether you’re a social butterfly or a lone wolf, the brain circuits that define social behaviors begin forming early in life and mature over a lifetime. But how the social brain develops has remained unclear, and new research explores oxytocin – often referred to as the “love hormone” – for answers.

Oxytocin earns its loving nickname because the brain releases the hormone during moments of social bonding, such as those between a parent and child or romantic partners . But beyond this role, oxytocin has long been thought to play a more direct role in social circuit development, and a recent study published in the Journal of Neuroscience put this idea to the test with zebrafish.

Zebrafish are social creatures with evolutionarily similar brain circuitry to humans. Scientists can genetically alter them before observing their behavior across an entire lifespan, making them ideal for studying social behavior. So to understand the role of oxytocin-producing neurons in social brain development, researchers selectively removed those neurons from their brain circuits early in life and examined the consequences to social behavior once the zebrafish reached adulthood.

The researchers evaluated the zebrafish behavior by first separating a fish from a larger group with a transparent barrier, then observing how the lone fish reacts to its isolation. Like a person with FOMO ("fear of missing out") from a party next door, socially healthy zebrafish stay close to the transparent barrier – seemingly longing to join the group on the other side. However, zebrafish with a disrupted social circuit explore their own tank with no preference to socialize.

Researchers found that zebrafish with their oxytocin neurons removed early in life showed less preference to socialize as adults. However, eliminating these cells in adulthood did not affect social behavior, suggesting that oxytocin shapes the social circuit early in life during a critical developmental window. They also found that removing oxytocin neurons early impaired other social brain components, including those required for attention, decision making, and reward.

Together, this suggests that the famous "love hormone" may define our long-term social preferences early in life. But unlike a Pixar movie, fish are not humans, and there is still more to learn about social brain development.

Wild Goffin's cockatoos can use tools, too

Scientists have observed captive cockatoos making tools before, but this is the first documented instance of tool use in wild cockatoos

Tool making is a complex behavior that, until recently, had only been confirmed in three species of primates (including humans), and in some birds, including captive Goffin's cockatoos . Now, a research group at the University of Vienna that has studied Goffin's cockatoos for decades has also observed the behavior in wild cockatoos . 

This species of cockatoo, a member of the parrot family, is comparable to three-year-old humans in terms of intelligence. But before now, tool making behavior has not been observed in wild cockatoos, which is necessary to confirm that a species is indeed capable of making tools and their tool use is not just an artifact of captivity.

The group spent over 884 hours observing wild birds in their natural habitat in the Tanimbar Islands, Indonesia, with no success in witnessing tool use and manufacture. They then moved on to a catch and release method, where they captured 15 individuals and placed them in temporary aviaries with many resources and a food option that finally encouraged more complex approaches to foraging: the Wawai fruit, or sea mango. The cockatoos really like eating the seeds of these fruits and need to go through the thick skin and flesh of the fruit in order to reach the seeds.

Two of the 15 individuals manufactured and used tools to extract sea mango seeds. Those two birds made tools by removing fragments from branches and then modifying them with their beaks. The researchers identified three different tool types: wedges, to widen the fissures to reach the seed inside the fruit; fine tools used for piercing the coating of the seed; and medium tools used for scooping the seeds. Furthermore, the tools were used sequentially, which the researchers believe to be the most complex example of tool use in a species without hands.

Both cockatoos proficiently manufactured and used the tools immediately after provided the Wawai fruit, suggesting they knew how to do that before capture. The fact that only two individuals were observed using tools indicates that this complex skill is not found species-wide and therefore has to be learned as a result of opportunity and innovation. This finding broadens our understanding of tool making ability beyond just primates .

Giant clams are growing faster than ever. That's not a good thing

This supercharged growth is likely due to nitrate aerosols in our modern atmosphere

Sarah Heidmann

Fish Ecology

University of the Virgin Islands

Photo by  NOAA  on  Unsplash

The growth of modern giant clams is supercharged compared to growth measured from fossil clams. A  recent study  from the Red Sea has shown this, finding that growth lines from modern species are larger than those of fossils from similar animals dated to the Holocene and Pleistocene.

These increased growth rates appear to be related to higher amounts of nitrate aerosols in the modern atmosphere. These come from  many different sources . Some are natural, such as  lightnin g,  biomass burning , and  soil processing , but  most are from anthropogenic activity  like burning fossil fuels and agricultural fertilization.

This fast growth may seem like a good thing, but growth doesn't mean anything about the overall health of the clams. Additionally, aerosols  may actually reduce the productivity  of marine phytoplankton, which represent  almost half  of the world's primary production.

The overall effects of nitrate and other aerosol pollution on global land and ocean cycles are  not well understood . They may appear to reduce global warming by improving carbon dioxide uptake and reflecting the sun's heat, but they contribute to poor air quality. We can congratulate today's super clams on their impressive growth. But in the long run, fewer emissions on our part are probably better for them.

Skeletons' broken clavicles tell a centuries-old tale of humans and horses

Clavicle fractures can be used to identify horse riders from their bones

Biological Anthropology

SNA International

Photo by Tim Mossholder on Unsplash

One thousand years ago, archers rode horses across the landscape of Hungary. They were probably intimidating, possibly threatening, and definitely adventurous, but just like equestrians today, they also fell a lot.

These horse riders remain a mystery. Who were they? Where were they from? When did they start riding horses? To answer these questions, an international team of scientists set out to find a way to identify horse riders from just their skeletons, using the fact that horse riders tend to fall. 

The researchers examined skeletons from a cemetery of well-known horse riders in Hungary dating to the 10th century CE. Riders in the cemetery were identified by horse riding equipment and horse bones in their graves. However, scientists could not be sure that skeletons without artifacts in the Hungarian cemetery never rode horses.  Therefore, they also investigated skeletons from another group of people from 20th century Portugal that definitely did not ride horses.

They found that upper body fractures were more common among riders, and that fractures of the clavicle (collar bone) were significantly more common among the Hungarian riders than the 20th century non-riders. To figure out if these fractures could be caused by horse riding, researchers turned to modern equestrians. Sure enough, fractures of the upper body, especially the clavicle, are some of the most commonly reported injuries in modern day equestrians.

The researchers argue that, in combination with other skeletal changes, clavicle fractures can be used to identify horse riders from just their skeletons. Being able to identify horse riders in the past could help researchers find the first horse riders, shedding light on the ways horse riding shaped human history.

Researchers observe a boar releasing two caged younglings in a impassioned rescue

The act sheds light on the prosocial behavior and empathy of wild boars, thought to be rare among animals

Oliver Völker from Pixabay

Humans aren't the only animals that step up to help others out of difficult situations. In a study recently published in the journal Scientific Reports, Michaela Masilkova of the Czech University of Life Sciences and her colleagues described a boar's daring rescue of two young wild boars stuck in a trap.

Few animals show this kind of rescue behavior: to go out of their way to help other members of their species that are caught in a dangerous situation. Masilkova's team inadvertently caught an astonishing act of altruism on camera while conducting a separate experiment to monitor wild boar movement for the prevention of African Swine Fever. The goal was to catch boars so the researchers could mark them individually. The researchers set up traps containing food as lure. Once lured inside, a boar would be caged in by logs that would roll off the top of the enclosure and bar the door shut. 

One night the trap — operating as usual — snared two young boars. But the night took an unexpected turn when a new herd arrived at the scene. One adult female took particular interest in the captives' predicament. Over the course of 29 minutes, the female pushed against the logs and successfully moved it, allowing the young boars to escape. Given that the rescuer spent so much time on this activity and showed physical signs of distress throughout, the researchers believed her act to be potential evidence of pro-social empathy.

This discovery suggests that complex forms of empathy may just be more common in the animal kingdom than scientists may have previously believed. 

Roe deer pause development of their embryos for months, and researchers just learned how

An embryonic phenomenon discovered over 150 years ago may finally have an explanation

Charlotte Douglas

Institut Curie Paris

Photo by Bob Brewer on Unsplash

In many species, not long after fertilization, the embryo implants into the uterus wall, preparing it for further development. In humans this implantation occurs at around day eight to nine after conception. However, in European roe deer, instead of implanting, the embryo stops developing, hovering in a period of dormancy.

This phenomenon has now been found in over 130 species, including mice and armadillos. But the roe deer have one of the longest known periods of embryonic suspension, lasting up to five months. This period is called diapause. Unlike in many of the other species that can induce diapause, cell division in roe deer embryos do not stop completely, but drastically slows, with cells dividing just once every few weeks.

Until now, the cellular mechanism that regulated the process of extensively slowing down cell replication was unknown. However, a recently published study in PNAS has uncovered it. Researchers discovered that a predominant driver of embryonic diapause is the changing abundance of amino acids in the embryo. One family of amino acids in particular were found to cause a significant increase in a protein called mTORC1, inducing the embryo to activate more of it. In fact, the increase of mTORC1 appeared to immediately coincide with the embryo’s exit from diapause, after which cells start dividing more rapidly, but was not detectable during the previous period of slow cell replication.

The mTOR protein family has been known for many years to be a crucial factor in regulating metabolic pathways, including in humans. In fact, a related protein called mTORC2 thought to be essential for maintaining slow cell divisions remains switched on throughout roe deer diapause. This new study will open up avenues of research into the precise timing of embryo implantation, as well as increasing our understanding about the interplay between the chemical and metabolic pathways of an animal and its embryo.

Female jumping spiders favor the most aggressive males

A new study provides evidence for sexual selection in these spiders

Hayden Waller

Cornell University

Photo by Timothy Dykes on Unsplash

If you've ever witnessed an overly aggressive guy get bounced from a bar, you probably found yourself internally judging him. But new research published in the journal Animal Behaviour suggests that the opposite may be true for spiders: the more aggressive a male jumping spider is, the sexier his female counterparts find him.

Researchers from the National University of Singapore quantified female spiders' preferences for aggressive males. They first placed males in a small chamber containing a mirror and observed how combative they were toward their own reflection. Once males had demonstrated either their contempt for or passivity towards their own reflections, they were paired with another male for a series of bouts. Using the results from the mirror test and combat trials, the researchers assigned each individual male spider an aggression predictability score. Finally, a pair of one highly aggressive male and one more passive male were placed in a chamber with a single female spider. Female preference was determined based on the amount of time she spent ogling each of her potential suitors. 

The researchers found that aggressive males are both more likely to defeat a rival in a combat trial, and to draw a higher amount of attention from females than their more pacifist competitors. They concluded that, not only is this evidence for sexual selection, but that the combination of strong competitiveness and female favor reinforce each other to push the most aggressive spiders to the top of the pile. 

People with sickle cell disease are less likely to get kidney transplants than those without

Sickle cell disease predominantly affects Black populations, and kidney transplants can save their lives

Keith Chambers via Wikimedia Commons (CC BY-SA 3.0 ) 

People with sickle cell disease encounter significant health issues such as kidney failure. Sickle cell disease, found predominantly in Black and African American populations, is when red blood cells are shaped like crescent moons (or “sickle-shaped”) instead of round and disc-like. This shape , which may have had evolutionary benefits during previous generations, can block blood flow, and therefore oxygen transport, through a person's body. 

Kidney failure is a major health complication encountered by people with sickle cell disease. Therefore, people with sickle cell disease are often reliant on dialysis treatment to filter the waste from their blood, but this is often not enough to save their lives. 

Therefore, researchers are exploring kidney transplantation as an additional treatment option for patients. In a study published in the Clinical Journal of the American Society of Nephrology , researchers used two national databases that collected information on adults from 1998-2017 with kidney failure who were on dialysis or the kidney transplant list. The researchers measured the impact of kidney transplantation on mortality, as well as differences in access to kidney transplants between people with and without sickle cell disease. 

People with sickle cell disease who were on dialysis had a higher mortality risk than the control group. However, the researchers found that transplantation reduced mortality risk for people with sickle cell disease as well as those without it, a benefit that lasted for at least ten years. 

Finally, the researchers found that patients with sickle cell were less likely to receive a transplant when compared to the control group, even though kidney transplantation has a higher likelihood of increasing the lifespan of sickle cell patients than does dialysis. This is yet another example of health inequity for Black and African American populations, and one with serious consequences, since kidney transplant is a life-saving intervention for people with sickle cell disease. 

Navigation Menu

Search code, repositories, users, issues, pull requests..., provide feedback.

We read every piece of feedback, and take your input very seriously.

Saved searches

Use saved searches to filter your results more quickly.

To see all available qualifiers, see our documentation .

• Notifications

This list of writing prompts covers a range of topics and tasks, including brainstorming research ideas, improving language and style, conducting literature reviews, and developing research plans.

ahmetbersoz/chatgpt-prompts-for-academic-writing

Folders and files, repository files navigation.

✨ NEW UPDATE: Literature Review Generator

A Custom GPT for Literature Review Generator has been released. It efficiently parses PDF files of research publications, extracts key themes, and creates a literature review section for your academic publications.

TRY NOW: https://chat.openai.com/g/g-G3U8pZGwC-literature-review-generator

ChatGPT Prompts for Academic Writing

In this repository, this list of writing prompts covers a range of topics and tasks, including brainstorming research ideas, improving language and style, conducting literature reviews, and developing research plans. Whether you're a student, researcher, or academic professional, these prompts can help you hone your writing abilities and tackle your writing projects with confidence.

Use directly in: chat.openai.com

The list is regularly updated, so you can keep track of new prompts by following this repository.

TIPS: As there is a limit to the number of words that can be used in ChatGPT, you can input your text multiple times using the prompt "Read this [PARAPGRAPH]:" and then run your final prompt "Considering the above text...".

You can also use prompts splitter: chatgpt-prompt-splitter.jjdiaz.dev

BRAINSTORMING

Article sections, title/topic sentence, introduction, literature review.

NOTE: Be careful and double-check article existence. ChatGPT may generate fake references

Methodology

Experiments, future works, improving language, summarization, plan/presentation, working with documents (available only in gpt-4).

Upload a PDF file of a paper then:

Upload a PDF file of your paper then:

Upload PDF files of papers then:

Upload a figure image then:

Contributors 4

An official website of the United States government

The .gov means it’s official. Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

The site is secure. The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

• Publications
• Account settings

Preview improvements coming to the PMC website in October 2024. Learn More or Try it out now .

• Advanced Search
• Journal List
• J Int Soc Sports Nutr

Common questions and misconceptions about creatine supplementation: what does the scientific evidence really show?

Jose antonio.

1 Department of Health and Human Performance, Nova Southeastern University, Davie, Florida USA

Darren G. Candow

2 Faculty of Kinesiology and Health Studies, University of Regina, Regina, Canada

Scott C. Forbes

3 Department of Physical Education, Faculty of Education, Brandon University, Brandon, MB Canada

Bruno Gualano

4 Applied Physiology & Nutrition Research Group; School of Medicine, FMUSP, University of Sao Paulo, Sao Paulo, SP Brazil

Andrew R. Jagim

5 Sports Medicine Department, Mayo Clinic Health System, La Crosse, WI USA

Richard B. Kreider

6 Exercise & Sport Nutrition Lab, Human Clinical Research Facility, Department of Health & Kinesiology, Texas A&M University, College Station, USA

Eric S. Rawson

7 Department of Health, Nutrition, and Exercise Science, Messiah University, Mechanicsburg, PA USA

Abbie E. Smith-Ryan

8 Department of Exercise and Sport Science, University of North Carolina, Chapel Hill, NC USA

Trisha A. VanDusseldorp

9 Department of Exercise Science and Sport Management, Kennesaw State University, Kennesaw, GA USA

Darryn S. Willoughby

10 School of Exercise and Sport Science, University of Mary Hardin-Baylor, Belton, TX USA

Tim N. Ziegenfuss

11 The Center for Applied Health Sciences, Canfield, Ohio USA

Associated Data

Not applicable.

Supplementing with creatine is very popular amongst athletes and exercising individuals for improving muscle mass, performance and recovery. Accumulating evidence also suggests that creatine supplementation produces a variety of beneficial effects in older and patient populations. Furthermore, evidence-based research shows that creatine supplementation is relatively well tolerated, especially at recommended dosages (i.e. 3-5 g/day or 0.1 g/kg of body mass/day). Although there are over 500 peer-refereed publications involving creatine supplementation, it is somewhat surprising that questions regarding the efficacy and safety of creatine still remain. These include, but are not limited to: 1. Does creatine lead to water retention? 2. Is creatine an anabolic steroid? 3. Does creatine cause kidney damage/renal dysfunction? 4. Does creatine cause hair loss / baldness? 5. Does creatine lead to dehydration and muscle cramping? 6. Is creatine harmful for children and adolescents? 7. Does creatine increase fat mass? 8. Is a creatine ‘loading-phase’ required? 9. Is creatine beneficial for older adults? 10. Is creatine only useful for resistance / power type activities? 11. Is creatine only effective for males? 12. Are other forms of creatine similar or superior to monohydrate and is creatine stable in solutions/beverages? To answer these questions, an internationally renowned team of research experts was formed to perform an evidence-based scientific evaluation of the literature regarding creatine supplementation.

Introduction

Creatine (methylguanidine-acetic acid) is endogenously formed from reactions involving the amino acids arginine, glycine and methionine in the kidneys and liver [ 1 ]. Exogenously, creatine is primarily consumed from meat and/or as a dietary supplement. According to PubMed (archive of biomedical and life sciences journal literature at the U.S. National Institutes of Health’s National Library of Medicine) there are over 500 peer-refereed publications involving various aspects of creatine supplementation. Based on the enormous popularity of creatine supplementation, the International Society of Sports Nutrition (ISSN) published an updated position stand in 2017 on the safety and efficacy of creatine supplementation in exercise, sport, and medicine [ 2 ]. This comprehensive paper provided an evidence-based review of the literature examining the effects of creatine supplementation on performance, recovery, injury prevention, exercise tolerance and rehabilitation, neuroprotection, aging, clinical and disease state populations, and pregnancy. Importantly, the safety profile of creatine was also reviewed. As of September 1, 2020, the paper has been viewed 179,000 times and cited 100 times (according to Web of Science). Furthermore, Altmetric data indicates that the paper has been mentioned in 19 news outlets, 4 blogs, 492 tweets, 54 Facebook pages, and been uploaded 69 times in video posts. Instagram stories and posts are not included as Altmetric data.

Despite the widespread outreach of the 2017 ISSN position stand paper [ 2 ], along with other evidence-based review/meta-analysis papers involving various aspects of creatine supplementation published after the 2015 Creatine in Health, Sport and Medicine Conference in Germany [ 3 – 34 ], questions and misconceptions involving creatine supplementation still remain. These include, but are not limited to: 1. Does creatine supplementation lead to water retention? 2. Is creatine is an anabolic steroid? 3. Does creatine supplementation cause kidney damage / renal dysfunction? 4. Does creatine supplementation cause hair loss / baldness? 5. Does creatine supplementation lead to dehydration and muscle cramping? 6. Is creatine supplementation harmful for children and adolescents? 7. Does creatine supplementation increase body fat? 8. Is a creatine supplementation ‘loading-phase’ required? 9. Is creatine supplementation beneficial for older adults? 10. Is creatine supplementation only useful for resistance/power type activities? 11. Is creatine supplementation only effective for males? 12. Are other forms of creatine similar or superior to monohydrate? Is creatine stable in solutions/beverages? To address these questions, an internationally renowned team of research experts, who have collectively published over 200 peer-refereed articles involving creatine supplementation, was formed to perform an evidence-based scientific evaluation of the literature. Each question was answered by one researcher, chosen according to her/his expertise on the topic. Then, the final version of this manuscript was reviewed and approved by all authors, therefore reflecting the group opinion.

Does creatine lead to water retention?

The purported myth of creatine supplementation increasing body water (TBW) is likely due to early research which showed that creatine supplementation at 20 g/day for six days was associated with water retention [ 35 ]. It does appear that the most common adverse effect of creatine supplementation is water retention in the early stages (first several days) [ 36 ]. For example, studies have shown that three days of creatine supplementation increased TBW and extracellular body water (ECW) [ 37 ] and intracellular water (ICW) [ 38 ]. Unfortunately, based on these short-term responses, this notion that creatine increases water retention over the long-term has been widely accepted [ 39 ].

Creatine is an osmotically active substance. Thus, an increase in the body's creatine content could theoretically result in increased water retention. Creatine is taken up into muscle from circulation by a sodium-dependent creatine transporter [ 1 ]. Since the transport involves sodium, water will also be taken up into muscle to help maintain intracellular osmolality. However, considering the activity of the sodium-potassium pumps, it is not likely that intracellular sodium concentration is dramatically affected by creatine supplementation [ 39 ].

A number of exercise training studies (e.g., 5-10 weeks) incorporating creatine supplementation have shown no increases in total body water (TBW). For example, resistance-trained males who received creatine at a dose of 0.3 g/kg lean body mass/day for 7 days (approximately 20 g/day) followed by 4 weeks at 0.075 g/kg lean body mass/day for 28 days (approximately 5 g/day) experienced no significant change in ICW, ECW, or TBW [ 40 ]. Furthermore, resistance-trained males who consumed creatine supplementation (20 g/day for seven days followed by 5 g/day for 21 days) had no significant increase in ICW, ECW, or TBW [ 41 ]. Similarly, males and females ingesting creatine (0.03 g/kg/day for six weeks) experienced no significant increase in TBW [ 42 ]. Six weeks of creatine supplementation in non-resistance-trained males at a dosage of 0.3 g/kg lean body mass for five days followed by 0.075 g/kg lean body mass for 42 days produced no significant changes in TBW [ 43 ]. In contrast, when assessing TBW, ICW, and ECW content before and after 28 days of creatine supplementation in healthy males and females (n = 32), Powers et al. [ 44 ] showed that creatine supplementation was effective at increasing muscle creatine content which was associated with an increase in body mass and TBW but did not alter ICW or ECW volumes. In a recent study examining the effects of creatine supplementation combined with resistance exercise for 8 weeks, Ribeiro et al. [ 45 ] found a significant increase in TBW (7.0%) and ICW (9.2%) volume compared to placebo (TBW: 1.7%; ICW: 1.6%), with both groups similarly increasing ECW (CR: 1.2% vs. Placebo = 0.6%). Importantly, the ratio of skeletal muscle mass to ICW remained similar in both groups. It is important to highlight that the ICW is an important cellular signal for protein synthesis and thus drives an increase in muscle mass over time [ 46 ].

In summary, while there is some evidence to suggest that creatine supplementation increases water retention, primarily attributed to increases in intracellular volume, over the short term, there are several other studies suggesting it does not alter total body water (intra or extracellular) relative to muscle mass over longer periods of time. As a result, creatine supplementation may not lead to water retention.

Is creatine an anabolic steroid?

Anabolic steroids are a synthetic version of testosterone, an androgenic hormone which is also produced endogenously within both males and females, and is used in conjunction with resistance training with the intent of enhancing muscle mass and strength due to increases in muscle protein synthesis [ 47 ]. This increase in MPS is due to testosterone’s ability to enter the muscle cell, bind with the intracellular androgen receptor, and increase the expression of various muscle-specific genes [ 48 ]. Creatine is converted to phosphocreatine (PCr), regulated by the enzyme creatine kinase (CK) in muscle and used to create intracellular adenosine triphosphate (ATP) production [ 1 ]. Creatine supplementation, however, can increase the capacity of ATP and energy produced during heavy anaerobically-related exercise, thereby possibly increasing muscle power, repetitions and exercise volume which can subsequently contribute to muscle performance and hypertrophy over the course of a training period [ 2 ].

While the physiological and performance outcomes of anabolic steroids and creatine can be similar, their mechanisms of action and legal categorization are not. Anabolic steroids are drugs, with a different chemical structure than creatine, and are Class C, Schedule III controlled substances regulated by the Food and Drug Administration (FDA) and subject to the regulatory control provisions of the Controlled Substances Act (CSA) set forth by the Drug Enforcement Association (DEA). Creatine, on the other hand, like many other dietary supplements fits well within the confines of The Dietary Supplement Health and Education Act of 1994 ("DSHEA"), which is a statute of United States Federal legislation which defines and regulates dietary supplements by the Federal Drug Administration (FDA) for Good Manufacturing Practices (GMP). It is illegal to possess and administer anabolic steroids without a physician’s prescription. However, there are no legal ramifications for the possession or ingestion of creatine.

In summary, because creatine has a completely different chemical structure, it is not an anabolic steroid.

Does creatine cause kidney damage/renal dysfunction?

Questions and concerns involving creatine supplementation and kidney damage/renal dysfunction are common. In terms of pervasive misinformation in the sport nutrition arena, the notion that creatine supplementation leads to kidney damage/renal dysfunction is perhaps second only to the myth that protein supplementation and high habitual protein intake causes kidney damage. Today, after > 20 years of research which demonstrates no adverse effects from recommended dosages of creatine supplements on kidney health, unfortunately, this concern persists. While the origin is unknown, the connection between creatine supplementation and kidney damage/renal dysfunction could be traced back to two things: a poor understanding of creatine and creatinine metabolism and a case study published in 1998.

In skeletal muscle, both creatine and PCr are degraded non-enzymatically to creatinine, which is exported to the blood and excreted in the urine [ 1 ]. Healthy kidneys filter creatinine, which would otherwise increase in the blood. Therefore, blood creatinine levels can be used as a proxy marker of kidney function. However, the amount of creatinine in the blood is related to muscle mass (i.e. males have higher blood creatinine than females) and both dietary creatine and creatinine intake [ 35 ]. Both blood and urinary creatinine may be increased by ingestion of creatine supplementation and creatine containing foods, such as meat. Creatine is normally not present in urine, but can reach very high levels (>10 g/day) during creatine supplementation [ 49 ]. There appears to be an unsubstantiated perspective that if the kidneys are “forced” to excrete higher than normal levels of creatine or creatinine, some sort of kidney “overload” will take place, causing kidney damage and/or renal dysfunction. In reality, transient increases in blood or urinary creatine or creatinine due to creatine supplementation are unlikely to reflect a decrease in kidney function. Additionally, one must exercise caution when using blood creatinine and estimated creatinine clearance/glomerular filtration rate in individuals who consume high meat intake or supplement with creatine. In a review of creatine supplementation studies, Persky and Rawson [ 50 ] found no increase in serum creatinine in 12 studies, 8 studies showed an increase that remained within the normal range, and only 2 studies showed an increase above normal limits (although not different from the control group in one study).

In 1998, a case study of a young male with focal segmental glomerulosclerosis and relapsing nephrotic syndrome was reported [ 51 ]. The young male, who had kidney disease for 8 years and was treated with cyclosporine (i.e., immunosuppressant) for 5 years, had recently begun ingesting creatine supplementation (15 g/day for 7 days; followed by 2 g/day for 7 weeks). Based on increased blood levels of creatinine and subsequent estimate of calculated creatinine clearance, his kidney health was presumed to be deteriorating, although he was otherwise in good health. The patient was encouraged to discontinue creatine supplementation. At this time, it was already known that blood and urine creatinine levels can increase following ingestion of creatine containing food products, including creatine supplements [ 35 ]. This was ignored by the authors of this case study, as was the inclusion of two investigations which demonstrated that creatine supplementation did not negatively impact renal function [ 52 , 53 ]. The dosage of creatine during the maintenance phase, which was also ignored, was only slightly higher than the daily creatine intake of a typical omnivore’s dietary intake, or in terms of food, a large hamburger or steak per day (meat contains about 0.7 g of creatine / 6 oz. serving; see [ 54 ]). In response to this case study, two separate teams of experts in creatine metabolism wrote letters to the editor of Lancet [ 53 , 55 ]. However, the notion that creatine supplementation leads to kidney damage and/or renal dysfunction gained traction and momentum.

Since this case study was reported in 1998, experimental and controlled research trials investigating the effects of creatine supplementation on kidney/renal function has substantially increased [ 50 , 56 – 58 ]. Overall, in healthy individuals, there appears to be no adverse effects from consuming recommended doses of creatine supplements on kidney/renal function [ 50 , 56 – 58 ]. Interestingly, Gualano et al. [ 58 ] reviewed a small number of case studies which reported renal dysfunction in individuals who were supplementing with creatine. Similar to the case report by Pritchard and Kalra [ 51 ], these additional case reports were confounded by medications, pre-existing kidney disease, concomitant supplement ingestion, inappropriate creatine dosages (e.g., 100 X recommended dose), and anabolic androgenic steroid use.

It is prudent to be cautious when ingesting any dietary supplement or medication. Survey data indicates that creatine supplementation usage ranges between 8-74% in athletes and other exercising individuals (reviewed in Rawson et al. [ 59 ]). Even with a low estimate of 8% of exercising individuals using creatine supplements, this indicates thousands of exposures across several decades. If the link between creatine supplementation and kidney health was valid, there would be an expected increase in kidney damage / renal dysfunction in low risk (i.e. young, physically fit, healthy) individuals since 1992 after Harris et al. published their seminal work [ 60 ]. After nearly 30 years of post-marketing surveillance, thousands of exposures, and multiple clinical trials, no such evidence exists.

In summary, experimental and controlled research indicates that creatine supplementation, when ingested at recommended dosages, does not result in kidney damage and/or renal dysfunction in healthy individuals.

Does creatine cause hair loss / baldness?

The vast majority of speculation regarding the relationship between creatine supplementation and hair loss/baldness stems from a single study by van der Merwe et al. [ 61 ] where college-aged male rugby players who supplemented with creatine (25 g/day for 7 days, followed by 5 g/day thereafter for an additional 14 days) experienced an increase in serum dihydrotestosterone (DHT) concentrations over time. Specifically, DHT increased by 56% after the seven-day loading period, and remained 40% above baseline values after the 14-day maintenance period. These results were statistically significant compared to when the subjects consumed a placebo (50 g of glucose per day for 7 days, followed by 30 g/day for 14 days thereafter). Given that changes in these hormones, particularly DHT, have been linked to some (but not all) occurrences of hair loss/baldness [ 62 ], the theory that creatine supplementation leads to hair loss / baldness gained some momentum and this potential link continues to be a common question / myth today. It is important to note that the results of van der Merwe et al. [ 61 ] have not been replicated, and that intense resistance exercise itself can cause increases in these androgenic hormones.

DHT is a metabolite of testosterone, formed when the enzyme 5-alpha-reductase converts free testosterone to DHT [ 63 ]. In males, DHT can bind to androgen receptors in susceptible hair follicles and cause them to shrink, ultimately leading to hair loss [ 64 ]. However, in the van der Merwe et al. [ 61 ] study, no increase in total testosterone was found in the 16 males who completed the study. Free testosterone was not measured. Moreover, the increase in DHT and the DHT: testosterone ratio remained well within normal clinical limits. Furthermore, baseline (prior to supplementation), DHT was 23% lower in the creatine group (0.98 nmol/L) compared to the placebo group (1.26 nmol/L). Thus the small increase in DHT in the creatine group (+ 0.55 nmol/L after 7 days of supplementation and + 0.40 nmol/L after 21 days of supplementation), in combination with a small decrease in the placebo DHT response (-0.17 nmol/L after 7 days of supplementation and -0.20 nmol/L after 21 days of supplementation) explains the “statistically significant” increase in DHT noted by van der Merwe et al. [ 61 ]. While it is possible that creatine supplementation upregulated 5-alpha-reductase activity in these males (potentially leading to increased formation of DHT), no study has reported hair loss/baldness in humans.

To date, 12 other studies have investigated the effects of creatine supplementation (i.e. doses ranging from 3-25 g/day for 6 days to 12 weeks) on testosterone. Two studies reported small, physiologically insignificant increases in total testosterone after six and seven days of supplementation [ 65 , 66 ], while the remaining ten studies reported no change in testosterone concentrations. In five of these studies [ 67 – 71 ], free testosterone, which the body uses to produce DHT, was also measured and no increases were found.

In summary, the current body of evidence does not indicate that creatine supplementation increases total testosterone, free testosterone, DHT or causes hair loss/baldness.

Does creatine lead to dehydration and muscle cramping?

Speculation exists that creatine supplementation causes dehydration and muscle cramping [ 72 , 73 ]. In the early 2000’s, with limited data and based primarily on speculation, the American College of Sports Medicine (ACSM) recommended that individuals controlling their weight and exercising intensely or in hot environments should avoid the use of creatine supplementation [ 74 ]. The physiological rationale suggesting that creatine supplementation may cause dehydration and muscle cramping is based on the premise that creatine is an osmotically active substance found primarily in skeletal muscle and may alter whole-body fluid distribution by preferentially increasing intracellular water uptake and retention, particularly over the short-term [ 38 , 75 ]. In situations of body water loss, such as severe sweating from exercise and/or increased environmental temperature, the bound intracellular fluid, in theory, may be detrimental to thermal regulation and lead to extracellular dehydration, electrolyte imbalance and muscle cramping or other heat-related musculoskeletal issues [ 44 ]. The initial loading phase of creatine supplementation (i.e. 20 g/day for 5-7 days) typically results in a 1-3 kg increase in body mass, mostly attributable to net body water retention [ 75 , 76 ]. Some anecdotal evidence indicates that creatine users perceive supplementation to result in some adverse effects [ 77 ]. For example, in a survey involving 219 athletes, 90 participants reported using creatine with 34 of them (38%) reporting perceived negative effects such as cramping (27%) [ 77 ]. Similarly, in National Collegiate Athletic Association (NCAA) Division 1 baseball and football players (N=52) using creatine, 25% reported incidences of muscle cramping and 13.5% reported symptoms of dehydration. Importantly, these studies failed to control for the use of other supplements and the dosage of creatine ingested. Greenwood et al. [ 77 ] noted that 91% of participants exceeded the recommended creatine maintenance dose of 5 g/day. However, these self-report surveys are in contradiction to experimental and clinical evidence. Greenwood et al. [ 78 ] monitored injury rates in Division IA NCAA collegiate football players (N=72; age: 19.7 ± 1.0 yrs) where environmental conditions were hot (27.3 ± 10.9 0 C) and humid (54.2 ± 9.7%). Participants chose to receive either creatine (n = 38: 0.3 g/kg/day for 5 days; followed by 0.03 g/kg/day for 115 days) or a sport drink placebo (n = 34) throughout the football season. Injuries treated by the athletic training staff were monitored. Creatine users had significantly less cramping (p = 0.021), heat illnesses and dehydration (p = 0.043), muscle tightness (p = 0.020), muscle strains (p = 0.021), and total injuries (p < 0.001) compared to non-users. Non-contact joint injuries, contact injuries, illnesses, missed practices due to injuries, and players lost for the season were not different between groups. In a clinical setting, haemodialysis patients (n = 10) who frequently reported muscle cramping were provided creatine (12 g) 5 minutes prior to haemodialysis [ 79 ]. Creatine supplementation reduced the frequency of symptomatic muscle cramping by 60% [ 79 ]. These beneficial effects from creatine may be explained by fluid distribution and electrolyte imbalances, as previously discussed.

In summary, experimental and clinical research does not validate the notion that creatine supplementation causes dehydration and muscle cramping.

Is creatine harmful for children and adolescents?

Concerns regarding the safety of creatine supplementation in children and adolescents (< 19 yrs) continues to be highly prevalent. The overwhelming majority of evidence in adult populations indicates that creatine supplementation, both short- and longer-term, is safe and generally well tolerated [ 2 ]. However, the question of whether or not this holds true for children and adolescents is relatively unclear. The physiological rationale supporting the potential ergogenic benefits of creatine supplementation in children and adolescents was first postulated by Unnithan and colleagues in 2001 [ 80 ]; which established a strong basis for future applications of creatine for younger athletes. More recently, in a comprehensive review examining the safety of creatine supplementation in adolescents, Jagim et al. [ 16 ] summarized several studies that examined the efficacy of creatine supplementation among various adolescent athlete populations and found no evidence of adverse effects. However, it is important to note that none of the performance-focused studies included in the Jagim et al. [ 16 ] review provided data examining specific markers of clinical health and whether or not they were impacted by the supplementation protocols.

From a clinical perspective, creatine supplementation has been found to potentially offer health benefits with minimal adverse effects in younger populations. Hayashi et al. [ 81 ] found improvements in pediatric patients with systemic lupus erythematosus and reported no adverse changes in laboratory parameters of hematology, kidney function, liver function or inflammatory markers after 12 weeks of creatine supplementation. Tarnopolsky et al. [ 82 ] reported significant improvements in fat-free mass and hand grip strength in 30 pediatric patients with Duchenne muscular dystrophy following 4 months of creatine supplementation. Importantly, the creatine supplementation protocol appeared to be well tolerated and did not adversely affect laboratory markers of kidney function, oxidative stress, and bone health [ 81 – 83 ]. In addition, Sakellaris et al. [ 83 ] reported significant improvements in traumatic brain injury-related outcomes in children and adolescents who received oral creatine supplementation (0.4 g/kg/day) for 6 months. These neurological benefits may have potential applications for young athletes participating in collision sports, which pose underlying risks of concussions or sub-concussive impacts. Further, several of these clinical trials implemented strict clinical surveillance measures, including continual monitoring of laboratory markers of kidney health, inflammation, and liver function; none of which were negatively impacted by the respective creatine supplementation interventions. These findings support the hypothesis of creatine supplementation likely being safe for children and adolescents. However, perhaps the strongest supporting evidence for the safety of creatine is the recent classification of creatine as generally recognized as safe (GRAS) by the United States Food and Drug Administration (FDA) in late 2020 ( https://www.fda.gov/media/143525/download ). Ultimately, this classification indicates that the currently available scientific data pertaining to the safety of creatine, is sufficient and has been agreed upon by a consensus of qualified experts, thereby determining creatine to be safe under the conditions of its intended use ( https://www.fda.gov/media/143525/download ). Even though infants and young children are excluded from GRAS, this would still apply to older children and adolescent populations.

The majority of dietary supplement survey data indicates that a relatively high percentage of youth and adolescent athletes are currently or have previously supplemented with creatine. For example, Kayton et al. [ 84 ] found that in a sample of 270 high school boys and girls, 21% of boys and 3% of girls reported supplementing with creatine. Furthermore, in a sample of elite Olympic level sample of young German athletes (14-18 yrs), 12% of those surveyed reported supplementing with creatine [ 85 ]. Therefore, these trends warrant additional research to determine with greater certainly whether creatine supplementation, both acute and longer-term, is safe for children and adolescents.

In summary, based on the limited evidence, creatine supplementation appears safe and potentially beneficial for children and adolescents.

Does creatine increase fat mass?

The theory that creatine supplementation increases fat mass is a concern amongst exercising individuals, possibly because some experience a gain in body mass from creatine supplementation. However, randomized controlled trials (one week to two years in duration) do not validate this claim. Acute creatine supplementation (7 days) had no effect on fat mass in young and older adults; however, fat-free mass was increased [ 86 , 87 ]. Furthermore, three weeks of creatine supplementation had no effect on body composition in swimmers [ 88 ]. The addition of creatine to high-intensity interval training had no effect on body composition in recreationally active females [ 89 ]. In addition, the effects of creatine supplementation during resistance training overreaching had no effect on fat mass [ 70 ]. Moreover, in a group of healthy recreational male bodybuilders, 5 g/day of creatine consumed either pre- or post-training had no effect on fat mass [ 90 ]. In other short-terms studies lasting 6-8 weeks, there were no changes in fat mass from creatine supplementation. Becque et al. [ 91 ] found no changes in fat mass after six weeks of supplementation plus resistance training. In another 6-week investigation, no significant differences in fat mass or percentage body fat were observed after creatine supplementation [ 42 ]. Furthermore, creatine supplementation during an 8-week rugby union football season also had no effect on fat mass [ 92 ].

One might suggest that eight weeks or less of creatine supplementation is insufficient to arrive at a definitive conclusion regarding creatine’s effect on fat mass. Nonetheless, there are several investigations that have used much longer treatment periods. For example, healthy resistance-trained males were randomly assigned in a double-blind fashion to supplement with creatine (i.e., 20 g/day for 1 week followed by 5 g/day for 11 weeks) or placebo [ 93 ]. Lean body mass and muscle fiber size increased; percent body fat and fat mass were unaffected over the 12-week training period [ 93 ]. In older males (~70 yrs), 12 weeks of creatine supplementation during resistance training had no effect (compared to placebo) on fat mass [ 94 ]. Furthermore, Gualano et al. assessed the effects of creatine supplementation (24 weeks), with and without resistance training, in older females. Results showed no effect from creatine on fat mass [ 95 ]. Candow et al. [ 96 ] examined the effects of creatine supplementation in older adults (50-71 years) over a 32-week treatment period. Study participants were randomized to supplement with creatine or placebo before or after resistance training (3 days per week). There was an increase over time for lean tissue and strength with a decrease in fat mass. From a clinical perspective, children with acute lymphoblastic leukemia who supplemented with creatine (0.1 g/kg/day) for two sequential periods of 16 weeks experienced a significant reduction in fat mass. In contrast, the children who did not consume creatine gained fat mass [ 97 ]. In two studies involving postmenopausal women, Lobo et al. [ 98 ] found no change in absolute or relative body fat from one-year of low-dose creatine supplementation. Furthermore, two years of creatine supplementation also had no effect on fat mass [ 99 ].

Recently, Forbes et al. [ 100 ] conducted a systematic review and meta-analysis on randomized controlled trials involving creatine supplementation in conjunction with resistance training on fat mass in older adults (≥ 50 yrs). Nineteen studies with a total of 609 participants were included. Participants supplementing with creatine had a greater reduction in body fat percentage. There was no significant difference in absolute fat mass loss; however, the creatine group lost ~0.5 kg more fat mass compared to those on placebo.

In summary, creatine supplementation does not increase fat mass across a variety of populations.

Is a creatine ‘loading-phase’ required?

Pioneering research in the early 1900’s using animal models showed that creatine supplementation could augment creatine content by 70% [ 101 , 102 ]. Decades later, Harris et al. [ 60 ] published a seminal paper which showed that ‘loading’ with creatine increased skeletal muscle creatine stores, as evaluated from muscle biopsies collected from the vastus lateralis in young, healthy human participants. This research sparked incredible interest in studying creatine supplementation strategies that would increase intramuscular creatine content, helping shape current recommendations.

Creatine ‘loading’ is defined as supplementing with oral creatine for 5–7 days with a dosage of 20–25 g/day, often divided into smaller doses throughout the day (e.g., four to five, 5 g servings/day). Creatine ‘loading’ may also be prescribed relative to body mass, for example, 0.3 g/kg/d for 5-7 days (i.e., 21 g/day for a 70 kg individual). The ‘loading’ phase of creatine supplementation is followed by a daily ‘maintenance’ phase often ranging from daily 3–5 g servings/day (Figure ​ (Figure1, 1 , side A). In addition to the seminal work of Harris et al. [ 60 ], several other investigations have demonstrated increased intramuscular creatine stores in humans from the creatine ‘loading’ phase [ 35 , 103 , 104 ]. A common misconception regarding creatine supplementation is that individuals must ‘load’ with creatine to increase intramuscular creatine stores and subsequently experience the purported ergogenic benefits of creatine supplementation. However, lower daily creatine supplementation dosing strategies (i.e., 3-5 g/day) are well established throughout the scientific literature for increasing intramuscular creatine stores leading to greater improvements in muscle mass, performance and recovery compared to placebo [ 2 ]. While effective, these non-loading creatine supplementation dosing strategies (Figure ​ (Figure1, 1 , side B) delay maximum intramuscular creatine storage. For example, in the classic ‘loading’ vs. daily ‘maintenance’ dose comparison study by Hultman et al. [ 35 ], creatine accumulation in muscle was similar (~ 20% increase) after participants consumed 3 g/day for 28 days or 20 g/day for 6 days [ 35 ]. Thus, it is currently recommended that individuals consume ~3-5 g/day of creatine for a minimum of 4 weeks in order to experience similar skeletal muscle saturation levels. Determination of which creatine supplementation strategy is preferred may depend on the goal of the individual. For instance, if an athlete is hoping to maximize the ergogenic potential of creatine supplementation in a very short period of time (< 30 days), adopting the creatine ‘loading’ strategy may be advised. However, if an athlete or exercising individual is planning to ingest creatine over an extended period of time (> 30 days), or if avoiding potential weight gain which can sometimes occur during creatine ‘loading’, the creatine ‘maintenance’ strategy would be a viable option. Athletes who are carrying out a creatine loading phase (i.e., 20 g/day) should emphasize the smaller dosing strategies (e.g. less than or equal to 10 gram servings) throughout the day, as dosages of greater than 10 grams may potentially lead to gastrointestinal distress (i.e., diarrhea) [ 105 ].

Creatine supplementation strategies.

In summary, accumulating evidence indicates that you do not have to ‘load’ creatine. Lower, daily dosages of creatine supplementation (i.e. 3-5 g/day) are effective for increasing intramuscular creatine stores, muscle accretion and muscle performance/recovery.

Is creatine beneficial for older adults?

There has been an increasing number of studies showing that creatine supplementation plays a therapeutic role in a variety of clinical conditions (see Gualano et al. [ 106 ] for a comprehensive review on this topic).

Perhaps one of the most promising conditions that could benefit from creatine supplementation is age-related sarcopenia. Sarcopenia is defined as a progressive and generalized skeletal muscle condition (i.e. decrease in muscle mass, strength, and functionality) that is associated with increased likelihood of adverse outcomes including falls, fractures, physical disability and mortality [ 107 ]. While resistance training is considered cornerstone in the treatment of sarcopenia [ 108 ], accumulating evidence indicates that creatine supplementation may enhance the anabolic environment produced by resistance training, subsequently mitigating indices of sarcopenia [ 9 , 10 , 19 , 27 ].

Creatine supplementation can increase functionality (e.g., strength, activities of daily living, delay fatigue) and muscle mass in older adults [ 9 , 10 , 19 , 87 , 95 , 109 , 110 ]. However, the literature indicates that creatine alone (that is, without a concomitant resistance training program) is unlikely to result in substantial gains in muscle strength and functional performance [ 95 , 111 – 113 ], although it does improve some parameters of muscle fatigue [ 114 – 116 ]. Likewise, most studies failed to show a beneficial effect of chronic creatine supplementation alone (≥ 30 days) on lean mass [ 98 , 99 , 113 , 114 ]. For instance, we recently showed that creatine supplementation was not able to increase lean mass in postmenopausal women who supplemented with creatine (3 g/day) for 2 years, suggesting that creatine supplementation without exercise may be ineffective to prevent sarcopenia [ 99 ]. It is likely that increases in lean mass occasionally attributed to creatine supplementation in short-term studies (e.g., 7 days) are explained by increased body water, since creatine is osmotically active and it can sometimes induce water retention.

Conversely, substantial evidence indicates that creatine supplementation is capable of augmenting the hypertrophic response to resistance training in young adults [ 117 ], which is extended to older adults, as confirmed by three systematic reviews and meta-analyses [ 19 , 118 , 119 ]. The fact that creatine is more effective when combined with a training stimulus suggests that the main mechanistic action of creatine is its ability to enhance training volume and/or intensity, which may influence muscle protein kinetics, growth factors, satellite cells, inflammation and/or oxidative stress [ 9 , 10 , 19 ], ultimately resulting in greater skeletal muscle adaptations.

Regarding aging bone, emerging research over the past decade has shown some benefits from creatine supplementation. For example, healthy older males (> 50 yrs) who supplemented with creatine and performed whole-body resistance training for 10-12 weeks experienced an increase in upper limb bone mineral content [ 120 ] and a reduction in bone resorption compared to placebo [ 121 ]. More recently, Chilibeck et al. [ 122 ] showed that 52 weeks of creatine supplementation and supervised whole-body resistance training attenuated the rate of bone mineral loss in the hip region compared to placebo in postmenopausal females. However, a 2 year creatine supplementation protocol was infective for improving bone mass or bone geometry in post-menopausal women, again suggesting that creatine should be combined with resistance-type exercise to produce beneficial bone adaptations [ 99 ].

From a clinical and healthy aging perspective, it is recommended that creatine supplementation be combined with resistance training to produce the greatest adaptations in older adults. Future clinical trials involving frail populations with long-term follow-up(s) and larger samples are needed. The therapeutic potential of creatine supplementation for cachexia, myopathies, post-surgery rehabilitation, bed rest, other muscle/bone wasting condition/diseases and brain health warrants further investigation.

In summary, there is growing body of evidence showing that creatine supplementation, particularly when combined with exercise, provides musculoskeletal and performance benefits in older adults.

Is creatine only useful for resistance / power type activities?

Although creatine supplementation has been theorized to primarily benefit athletes involved in high-intensity intermittent resistance/power type activities, there is a growing body of evidence suggesting that creatine supplementation may also provide beneficial effects for other activities. For example, creatine supplementation with carbohydrate [ 123 ] or carbohydrate and protein [ 124 ] has been reported to promote greater muscle glycogen storage than carbohydrate supplementation alone. Since glycogen replenishment is important for promoting recovery and preventing overtraining during intensified training periods [ 2 , 125 ], creatine supplementation may help athletes who deplete large amounts of glycogen during training and/or performance (i.e., sporting events) to maintain optimal glycogen levels. Second, there is evidence that creatine supplementation may reduce muscle damage and/or enhance recovery from intense exercise. For example, Cooke and colleagues [ 126 ] reported that creatine supplementation during recovery from exercise-induced muscle damage promoted less muscle enzyme efflux and better maintenance of isokinetic muscle performance. Moreover, there is evidence that individuals supplementing their diet with creatine experienced less muscle damage, inflammation, and muscle soreness in response to running 30-km [ 127 ] as well as during 4-weeks of intensified training [ 70 ]. Consequently, creatine supplementation may help athletes recover from intense exercise and/or tolerate intensified periods of training to a greater degree. Third, there is evidence that athletes who supplement with creatine during training experience fewer musculoskeletal injuries, accelerated recovery time from injury [ 78 , 128 ] and less muscle atrophy after immobilization [ 129 , 130 ]. Whether this is due to a greater resistance to injury and/or ability to recover from injury remains unclear. Fourth, creatine supplementation (with or without glycerol) has been reported to help athletes hyper-hydrate and thereby enhance tolerance to exercise in the heat [ 28 , 37 , 131 – 145 ]. Therefore, creatine supplementation may reduce the risk of heat related-illness when athletes train and/or compete in hot and humid environments [ 72 , 146 ]. Finally, there is evidence from animal models that creatine supplementation is neuroprotective [ 147 – 149 ] and can reduce the severity of spinal cord injury [ 150 , 151 ], cerebral ischemia [ 152 – 155 ], and concussion/traumatic brain injury [ 2 , 7 , 12 , 22 , 32 , 33 , 156 ]. This evidence was so compelling that the International Society of Sports Nutrition recommended that athletes engaged in sports that have a potential for concussion and/or spinal cord injury take creatine for its neuroprotective effects [ 2 ]. Thus, there are a number of reasons beyond the ergogenic benefit that all types of athletes may benefit.

In summary, there is a variety of athletic events, not just resistance/power activities, which may benefit from creatine supplementation.

Is creatine only effective for males?

Creatine kinetics may vary between healthy males and females [ 157 ]. Females may have higher intramuscular creatine concentrations [ 158 ] possibly due to lower skeletal muscle mass [ 159 ]. Potentially, the higher resting intramuscular creatine concentration in females (based on the upper limit of intramuscular creatine storage) may help explain some research showing diminished responsiveness and/or performance effects on females [ 160 , 161 ].

As a result of hormone-driven changes in endogenous creatine synthesis, creatine transport, and creatine kinase (CK) kinetics, creatine bioavailability throughout various stages of female reproduction is altered, highlighting the potential positive implications for creatine supplementation in females [ 29 ]. The implications of hormone-related changes in creatine kinetics has been largely overlooked in performance-based studies [ 29 ]. Specifically, creatine supplementation may be of particular importance during menses, pregnancy, post-partum, perimenopause and postmenopause. Creatine kinase, as well as enzymes associated with creatine synthesis, are influenced by estrogen and progesterone [ 1 ]. Creatine kinase levels are significantly elevated during menstruation [ 162 ], with CK levels decreasing throughout the menstrual cycle, pregnancy, and with age. The lowest range of CK values have been reported during early pregnancy (20 weeks or less), equating to about half the concentration found at peak levels (teenage girls) [ 162 , 163 ].

Maternal creatine supplementation during pregnancy in pre-clinical animal studies have demonstrated a protective effect against fetal death and organ damage associated with intrapartum hypoxia [ 164 , 165 ]. Reduced creatine levels in late pregnancy have also been associated with low fetal growth [ 165 ]. There is additional data that metabolic demand from the placenta during gestation further lowers the creatine pool of the mother [ 166 ], which may be associated with low birth weight and pre-term birth. Creatine supplementation during pregnancy has been shown to enhance neuronal cell uptake of creatine and support mitochondrial integrity in animal offspring, thereby reducing brain injury induced by intrapartum asphyxia [ 167 , 168 ]. Although there are no human studies evaluating the effects of creatine supplementation during pregnancy, creatine could provide a safe, low-cost nutritional interventional for reducing intra- and post-partum complications associated with cellular energy depletion [ 169 ]. This may be more important if the female is vegetarian, or unable to consume meat due to nausea or taste preferences (i.e. meat contains about 0.7 g of creatine/6 oz serving [ 54 ];).

Females have been reported to have lower levels of creatine in the brain (frontal lobe) [ 170 ]. Increasing creatine concentrations in the brain as a result of supplementation, particularly in females, may support the reported benefits of reducing symptoms of depression [ 171 , 172 ] and ameliorating the effects of traumatic brain injury [ 12 , 22 ]. Depression is about 2 times higher among females throughout the reproductive years [ 173 ] and accelerates around pubertal hormonal changes [ 174 ]. Altered brain bioenergetics and mitochondrial dysfunction have been linked with depression, particularly as it relates to CK, ATP, and inorganic phosphate (P i ). Creatine supplementation has been shown to significantly augment cerebral PCr and P i [ 175 ], particularly in females. The increase in cerebral PCr from 10 g of creatine supplementation was reported to be inversely related to symptoms of depression in adolescent females resistant to selective serotonin reuptake inhibitors [ 171 ] It appears that creatine supplementation may be effective for supporting creatine kinetics, mood, and pregnancy/fetal outcomes.

There is a small body of research that has investigated the effects of creatine supplementation in younger females. For example, Vandenberghe et al. [ 176 ] showed that creatine supplementation (20 g/day for 4 days followed by 5 g/day thereafter) during 10 weeks of resistance training significantly increased intramuscular concentrations, muscle mass and strength compared to placebo in females (19-22 yrs). In elite female soccer players (22 ± 5 yrs), creatine supplementation (20 g/day for 6 days) improved sprint and agility performance compared to placebo [ 177 ]. Hamilton et al. [ 178 ] showed that creatine supplementation (25 g for 7 days) augmented upper-body exercise capacity in strength-trained females (21-33 yrs) compared to placebo (19-29 yrs). Furthermore, in college-aged females (20 yrs), creatine supplementation (0.5 g/kg of fat-free mass for 5 days) improved knee extension muscle performance compared to placebo [ 179 ]. In contrast, not all data show improved performance in females [ 89 , 160 , 161 ]. Additionally, Smith-Ryan et al. [ 180 ] reported no significant effects of creatine loading on neuromuscular properties of fatigue in young adult females. It is important to evaluate the benefit to risk ratio; as noted elsewhere in this document, there are minimal risks associated with creatine supplementation, particularly when it is evaluated against the potential benefits in females.

Accumulating research over the past decade in postmenopausal females demonstrates that creatine supplementation during a resistance training program can improve muscle mass, upper- and lower-body strength, and tasks of functionality (30-s chair stand, lying prone-to-stand test, arm curl test) (for detailed review see Candow et al. [ 9 ]). Creatine supplementation appears to be a viable option for post-menopausal females to improve muscle quality and performance. In addition to its beneficial effects on aging muscle, creatine supplementation may also have favorable effects on bone in postmenopausal females, if combined with resistance training. For example, postmenopausal females who supplemented daily with 0.1 g/kg/day of creatine during 52-weeks of supervised whole-body resistance training experienced an attenuation in the rate of bone mineral loss at the femoral neck (hip), compared to females on placebo during training [ 122 ]. Furthermore, 5 g/day of creatine supplementation during 12 weeks of resistance training in postmenopausal females resulted in a significant increase in muscle mass and upper- and lower-body strength, compared to placebo [ 181 ]. However, even without the stimulus of resistance training, there is some evidence that creatine supplementation can still be beneficial. For example, in aging females (n=10; 67 ± 6 yrs), acute creatine supplementation (0.3 g/kg/day for 7 days) significantly improved lower-extremity physical performance (sit-to-stand test) [ 110 ], and fat-free mass and upper- and lower-body strength compared to placebo [ 86 ].

In summary, there is accumulating evidence that creatine supplementation has the potential to be a multifactorial therapeutic intervention across the lifespan in females, with little to no side effects.

Are other forms of creatine similar or superior to monohydrate and is creatine stable in solutions/beverages?

Creatine monohydrate powder has been the most extensively studied and commonly used form of creatine in dietary supplements since the early 1990s [ 2 , 125 ]. Creatine monohydrate was used in early studies to assess bioavailability, determine proper dosages, and assess the impact of oral ingestion of creatine on blood creatine and intramuscular creatine stores [ 35 , 60 , 182 ]. These studies indicated that orally ingested creatine monohydrate (e.g., 3–5 g/day) increases blood concentrations of creatine for 3-4 hours after ingestion thereby facilitating the uptake of creatine into tissue through diffusion and creatine transporters [ 1 , 183 , 184 ]. Additionally, it is well established that ~99% of orally ingested creatine monohydrate is either taken up by tissue or excreted in the urine as creatine through normal digestion [ 60 , 185 , 186 ]. Short-term loading with creatine monohydrate (e.g., consuming 5 g, 4 times daily for 5-7 days) has been reported to increase intramuscular creatine stores by 20–40% and exercise performance capacity by 5–10% [ 2 , 125 ]. Creatine monohydrate supplementation during training (e.g., 5–25 g/day for 4–12 weeks) has been reported to promoted gains in muscle mass, strength, and exercise capacity [ 2 , 125 ]. Despite the known efficacy, safety, and low cost of creatine monohydrate; a number of different forms of creatine have been marketed as more effective with fewer anecdotally reported adverse effects [ 187 ]. These marketing efforts have fueled speculation that creatine monohydrate is not the most effective or safest form of creatine to consume. This notion is clearly refuted by understanding the well-known physio-chemical properties of creatine monohydrate, as well as current creatine supplementation literature.

A number of different forms of creatine (e.g., creatine salts, creatine complexed with other nutrients, creatine dipeptides, etc.) have been marketed as more effective sources of creatine than creatine monohydrate [ 187 ]. However, there are no peer-reviewed published papers showing that the ingestion of equal amounts of creatine salts [ 188 – 191 ] or other forms of creatine like effervescent creatine [ 128 ], creatine ethyl ester [ 43 , 192 , 193 ], buffered creatine [ 41 ], creatine nitrate [ 194 , 195 ], creatine dipeptides, or the micro amounts of creatine contained in creatine serum [ 196 ] and beverages (e.g., 25–50 mg) increases creatine storage in muscle to a greater degree than creatine monohydrate [ 187 ]. In fact, most studies show that ingestion of these other forms have less physiological impact than creatine monohydrate on intramuscular creatine stores and/or performance and that any performance differences were more related to other nutrients that creatine is bound to or co-ingested with in supplement formulations. This makes sense given that these other forms contain less creatine per gram than creatine monohydrate and that 99% of ingested creatine monohydrate is absorbed into the blood, then taken up into muscle, or excreted in urine [ 187 ].

Creatine monohydrate crystallizes from water as monoclinic prisms that hold one molecule of water of crystallization per molecule of creatine [ 187 ]. Subsequent drying of creatine monohydrate at about 100°C removes the water of crystallization yielding anhydrous creatine (100% creatine) [ 187 ]. Creatine is considered a weak base (pKb 11.02 at 25°C) that can only form salts with strong acids (i.e., pKa < 3.98). Creatine can also serve as a complexing agent with other compounds via ionic binding. Creatine monohydrate powder contains the highest percentage of creatine (87.9%) other than creatine anhydrous [ 187 ]. Creatine monohydrate manufactured in Germany involves adding acetic acid to sodium sarconsinate, heating, adding cyanamide, cooling to promote crystallization, separation and filtration, and drying has been reported to produce 99.9% pure creatine monohydrate with no contaminants. Meanwhile, other sources of creatine monohydrate that have different starting materials (e.g., sarcosinates and O-alkylisourea, sarcosinates and S-alkylisothiourea) and methods of creatine synthesis, particularly from sources produced in China, have been found to contain up to 5.4% dicyandiamide, 0.09% dihydrotriazine, 1.3% creatinine, dimethyl sulphate, thiourea, and/or higher concentrations of heavy metals like mercury and lead due to use of different chemical precursors, poorly controlled synthesis processes, and/or inadequate filtration methods that more readily produce these contaminants [ 197 ]. While the effects of ingesting these compounds on health are unknown, contamination with dihydrotriazine has been suggested to be of greatest concern since it is structurally related to carcinogenic compounds [ 197 ]. For this reason, German sourced creatine monohydrate has been primarily used in research to establish safety and efficacy and is therefore the recommended source of creatine monohydrate to use in dietary supplements [ 2 , 187 ].

Creatine monohydrate powder is very stable showing no signs of degradation into creatinine over years, even at elevated storage temperatures [ 187 ]. However, creatine is not stable in solution due to intramolecular cyclization that converts creatine to creatinine especially at higher temperatures and lower pH [ 187 , 198 – 200 ]. The degradation of creatine can be reduced or halted by lowering the pH under 2.5 or increasing the pH above 12.1 [ 187 ]. This is the reason that less than 1% of creatine monohydrate is degraded to creatinine during the digestive process and creatine is taken up by tissue or excreted in urine after ingestion [ 60 , 185 – 187 ]. Moreover, since creatine is an ampholytic amino acid, it is not very soluble in water (e.g., creatine monohydrate dissolves at 14 g/L at 20°C with a neutral pH of 7) [ 187 ]. Mixing creatine in higher temperature solution increase solubility, which is the reason why initial studies administered creatine in hot tea [ 35 , 60 , 103 , 104 , 123 , 182 ] but the solubility has no influence on tissue uptake [ 187 ]. The lack of solubility and stability of creatine in solution is the reason that creatine is primarily marketed in powder form and efforts to develop stable beverages containing physiologically effective doses of creatine (e.g., 3–5 g per serving) have been unsuccessful.

In summary, while some forms of creatine may be more soluble than creatine monohydrate when mixed in fluid, evidence-based research clearly shows creatine monohydrate to be the optimal choice.

Conclusions

Based on our evidence-based scientific evaluation of the literature, we conclude that:

• Creatine supplementation does not always lead to water retention.
• Creatine is not an anabolic steroid.
• Creatine supplementation, when ingested at recommended dosages, does not result in kidney damage and/or renal dysfunction in healthy individuals.
• The majority of available evidence does not support a link between creatine supplementation and hair loss / baldness.
• Creatine supplementation does not cause dehydration or muscle cramping.
• Creatine supplementation appears to be generally safe and potentially beneficial for children and adolescents.
• Creatine supplementation does not increase fat mass.
• Smaller, daily dosages of creatine supplementation (3-5 g or 0.1 g/kg of body mass) are effective. Therefore, a creatine ‘loading’ phase is not required.
• Creatine supplementation and resistance training produces the vast majority of musculoskeletal and performance benefits in older adults. Creatine supplementation alone can provide some muscle and performance benefits for older adults.
• Creatine supplementation can be beneficial for a variety of athletic and sporting activities.
• Creatine supplementation provides a variety of benefits for females across their lifespan.
• Other forms of creatine are not superior to creatine monohydrate.

Acknowledgments

Abbreviations, authors’ contributions.

Conceptualization: DGC; Writing-original draft preparation: All authors. The authors declare that the content of this paper has not been published or submitted for publication elsewhere. The author(s) read and approved the final manuscript.

Availability of data and materials

Ethics approval and consent to participate, consent for publication.

Not applicable

Competing interests

JA is Chief Executive Officer of the ISSN, an academic non-profit that receives support and/or sponsorship from companies that manufacture and/or sell creatine or creatine-containing products.

DGC has received research grants and performed industry sponsored research involving creatine supplementation, received creatine donation for scientific studies and travel support for presentations involving creatine supplementation at scientific conferences. In addition, DGC serves on the Scientific Advisory Board for Alzchem (a company which manufactures creatine) and the editorial review board for the Journal of the International Society of Sports Nutrition and is a sports science advisor to the ISSN. Furthermore, DGC has previously served as the Chief Scientific Officer for a company that sells creatine products.

SCF has served as a scientific advisor for a company that sells creatine products.

BG has received research grants, creatine donation for scientific studies, travel support for participation in scientific conferences (includes the ISSN) and honorarium for speaking at lectures from AlzChem (a company which manufactures creatine). In addition, BG serves on the Scientific Advisory Board for Alzchem (a company that manufactures creatine).

ARJ has consulted with and received external funding from companies that sell certain dietary ingredients and also writes for online and other media outlets on topics related to exercise and nutrition

RBK is co-founder and member of the board of directors for the ISSN. In addition, RBK has conducted industry sponsored research on creatine, received financial support for presenting on creatine at industry sponsored scientific conferences (includes the ISSN), and served as an expert witness on cases related to creatine. Additionally, he serves as Chair of the Scientific Advisory Board for Alzchem that manufactures creatine monohydrate.

ESR serves on the Scientific Advisory Board for Alzchem (a company which manufactures creatine). In addition, ESR received financial compensation to deliver the President’s Lecture on creatine supplementation at the 2019 ISSN annual conference.

AESR has received research funding from industry sponsors related to sports nutrition products and ingredients. In addition, AESR serves on the Scientific Advisory Board for Alzchem (a company that manufactures creatine).

TAV has received funding to study creatine and is an advisor for supplement companies who sell creatine. In addition, TAV is the current president of the ISSN.

DSW serves as a scientific advisor to the ISSN and on the editorial review board for the Journal of the International Society of Sports Nutrition. In addition, DSW is Past President of the ISSN and has received financial compensation from the ISSN to speak about creatine supplementation.

TNZ has conducted industry sponsored research involving creatine supplementation and has received research funding from industry sponsors related to sports nutrition products and ingredients. In addition, TNZ serves on the editorial review board for the Journal of the International Society of Sports Nutrition and is Past President of the ISSN.

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

• Human Resource
• Business Strategy
• Operations Management
• Project Management
• Business Management
• Supply Chain Management
• Scholarship Essay
• Narrative Essay
• Descriptive Essay
• Buy Essay Online
• College Essay Help
• Help To Write Essay Online

How can I be sure you will write my paper, and it is not a scam?

Courtney Lees

Finished Papers