A Summary of the article on “Common questions and misconceptions about creatine supplementation: what does the scientific evidence really show?”
Background
The article, authored by Antonio J, Candow D, Forbes S et al (2021), was published in the Journal of the International Society of Sports Nutrition in February 2021 and addresses twelve common myths and questions surrounding creatine supplementation by evaluating the current scientific literature. An internationally renowned team of research experts compiled this evidence-based review to provide clarity on the efficacy and safety of creatine.
Results
Here is a summary of the article’s findings on key misconceptions:
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Creatine does not consistently lead to long-term water retention. While early research suggested that creatine supplementation, particularly during the initial loading phase (20 g/day for several days), could cause short-term water retention, specifically increases in total body water (TBW), extracellular water (ECW), and intracellular water (ICW), this notion is largely disproven for long-term use. Numerous exercise training studies, incorporating creatine over 5-10 weeks, have shown no increases in TBW, ICW, or ECW relative to muscle mass.
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Creatine is not an anabolic steroid. Anabolic steroids are synthetic versions of testosterone, legally classified as Class C, Schedule III controlled substances by the FDA, and are illegal to possess without a prescription. Creatine, on the other hand, has a completely different chemical structure and mechanism of action. It functions by increasing the capacity for ATP production during high-intensity exercise, which can contribute to muscle performance and hypertrophy over time. Creatine is regulated by the FDA as a dietary supplement under The Dietary Supplement Health and Education Act of 1994 (DSHEA).
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Creatine supplementation does not cause kidney damage or renal dysfunction in healthy individuals. This widespread misconception likely stems from a poor understanding of creatine and creatinine metabolism and a single 1998 case study. Creatinine, a breakdown product of creatine, is filtered by the kidneys, and its blood levels can increase with creatine intake or high meat consumption, but this does not indicate kidney damage. Extensive research over 20 years, involving thousands of exposures and multiple clinical trials, confirms no adverse effects on kidney function from recommended dosages in healthy individuals. Case reports of renal dysfunction linked to creatine have often been confounded by pre-existing kidney disease, other medications, or inappropriate dosages.
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There is no scientific evidence that creatine causes hair loss or baldness. This speculation largely originates from one study in college-aged rugby players where creatine supplementation was associated with an increase in dihydrotestosterone (DHT). However, this finding has not been replicated, and the reported increase in DHT remained within normal clinical limits. Furthermore, intense resistance exercise itself can increase androgenic hormones. Twelve other studies examining creatine’s effect on testosterone have found no significant increases in total or free testosterone.
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Creatine supplementation does not cause dehydration or muscle cramping. Initial concerns, partly based on speculation, led some to recommend avoiding creatine in hot environments. However, experimental and clinical research contradicts this. Studies show that creatine users experienced significantly less cramping, heat illnesses, and dehydration compared to non-users during a football season. Creatine has even been shown to reduce muscle cramps in haemodialysis patients. Its potential to help athletes hyper-hydrate may actually reduce the risk of heat-related illness.
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Creatine appears safe and potentially beneficial for children and adolescents. Although research is limited compared to adults, reviews have found no evidence of adverse effects in adolescent athletes. Clinically, creatine supplementation has shown health benefits with minimal side effects in pediatric patients with conditions like systemic lupus erythematosus and Duchenne muscular dystrophy, improving fat-free mass and strength. The United States FDA’s classification of creatine as Generally Recognized As Safe (GRAS) in late 2020 further supports its safety, applying to older children and adolescents.
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Creatine supplementation does not increase fat mass. While some individuals may experience a body mass gain due to increased body water (especially short-term), randomized controlled trials lasting from one week to two years consistently show no increase in fat mass across various populations. In fact, some evidence suggests creatine, particularly when combined with resistance training in older adults, can lead to a reduction in body fat percentage and absolute fat mass.
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A creatine ‘loading-phase’ is not required. While a loading phase (20-25 g/day for 5-7 days) can rapidly increase intramuscular creatine stores, lower daily dosages (3-5 g/day) are also effective over a minimum of four weeks to achieve similar muscle saturation levels. The choice of strategy depends on the individual’s goal: loading for quick maximisation (e.g., short period before competition) or maintenance for extended use, potentially avoiding initial weight gain or gastrointestinal distress associated with high doses.
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Creatine is beneficial for older adults, especially when combined with exercise. Creatine supplementation, particularly alongside resistance training, can significantly enhance muscle mass, strength, functionality, and bone health in older adults, helping to mitigate age-related sarcopenia. While creatine alone may improve some parameters of muscle fatigue, its most substantial benefits on lean mass and functional performance are observed when combined with a training program.
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Creatine is not only useful for resistance/power activities. Beyond its known benefits for high-intensity exercise, creatine supplementation can also aid in muscle glycogen storage, reduce muscle damage, enhance recovery from intense exercise, and potentially prevent injuries. It can also help athletes hyper-hydrate to improve exercise tolerance in the heat and has shown neuroprotective effects, leading to recommendations for athletes in collision sports due to potential concussion risks.
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Creatine provides a variety of benefits for females across their lifespan. While some research suggests females may have higher baseline intramuscular creatine, possibly influencing responsiveness, hormonal changes throughout the female reproductive cycle (menses, pregnancy, postpartum, perimenopause, postmenopause) affect creatine kinetics. Creatine supplementation has shown potential benefits during pregnancy for fetal protection and maternal creatine pools, and for reducing symptoms of depression due to lower brain creatine levels in females. Studies show creatine can improve muscle mass, strength, and functionality in young and postmenopausal females, especially with resistance training, and may have favourable effects on bone health in older women.
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Creatine monohydrate remains the optimal form of creatine. It is the most extensively studied and commonly used form, with high bioavailability (approximately 99% absorbed) and proven efficacy for increasing intramuscular creatine stores and improving performance. Despite marketing claims, no other forms (e.g., creatine salts, ethyl ester, buffered creatine) have been scientifically shown to be superior or even comparable to creatine monohydrate in terms of increasing muscle creatine content or performance. Creatine monohydrate powder is stable, but it degrades in solution, especially at higher temperatures and lower pH, which is why it is primarily marketed as a powder. German-sourced creatine monohydrate is recommended due to its purity and established safety.
Conclusions
In conclusion, the scientific evidence strongly supports the safety and efficacy of creatine supplementation, particularly creatine monohydrate, for various populations and purposes, debunking many common misconceptions.
References
Antonio, J., Candow, D. G., Forbes, S. C., Gualano, B., Jagim, A. R., Kreider, R. B., Rawson, E. S., Smith-Ryan, A. E., VanDusseldorp, T. A., Willoughby, D. S., & Ziegenfuss, T. N. (2021). Common questions and misconceptions about creatine supplementation: What does the scientific evidence really show? Journal of the International Society of Sports Nutrition, 18(1), 13. https://doi.org/10.1186/s12970-021-00412-w
This post is based on Open Access research and is for informational purposes only.
