Creatine has often been purported to have negative implications for health but are these claims warranted?
Not at all.
Creatine is one of the most widely studied supplements on the market and there is a huge body of scientific evidence to support its efficacy and safety as an ergogenic aid. Emerging evidence is also growing on the benefits of creatine supplementation outside of exercise performance parameters. A special mention here is to the highly interesting and promising results on brain health.
What is creatine?
Creatine is a naturally occurring non-protein amino acid compound that is primarily found in red meat and seafood. There are endogenous stores of creatine in skeletal muscle with 95% of our stores found there and the remaining 5% in the brain and testes. Creatine supplementation leads to increases in intramuscular creatine concentrations which can lead to performance improvements and positive training adaptations.
Two thirds of these skeletal muscle stores are in the form of phosphocreatine (PCr) while the remaining third is free creatine. The main metabolic role of creatine is to combine with a phosphoryl group (Pi) to form PCr through the action of the enzyme creatine kinase.
As ATP (the energy currency of the cell) is broken down to ADP and Pi to provide free energy for metabolic activity. The free energy released from the hydrolysis of PCr into Cr and Pi can then be used to resynthesize ATP. By supplementing with creatine, the resynthesis of ATP can be maintained at high rates for longer periods due to increase in endogenous stores. The significance of this is seen in bouts of exercise where rapid, explosive movements are required, such as sprinting and lifting weights. A greater work capacity is evident after supplementation which has downstream benefits such as leading to a hypertrophic response.
What are the claims?
There are many claims around creatine, ranging from weight gain to impaired renal function. For the most part these claims are not supported apart from the often-reported weight gain by way of greater water retention as a result increases intracellular water volume.
The common misleading health claims include:
- That it is an anabolic steroid
- It causes renal dysfunction
- It causes hair loss
- It causes weight gain
Is creatine an anabolic steroid?
An anabolic steroid is a synthetic version of the hormone testosterone. Testosterone is an endogenous compound that can aid in strength and muscle gain by way of entering the muscle cell and increasing the expression of various muscle-specific genes.
Anabolic steroid use is linked to a host of negative health implication on both physiological and psychological levels. Creatine on the other hand is non-protein amino acid that helps resynthesize ATP and thus allows for more work to be completed. This increase in work capacity can aid training performance and lead to adaptations like those seen with anabolic steroids with respect to morphological change and increased strength. Despite similar outcomes, they are complete opposites in terms of mechanisms of action and chemical structure.
Does creatine cause renal dysfunction?
This is probably the most common myth when it comes to creatine. In skeletal muscle, both PCr and creatine are degraded to creatinine. Creatinine is exported to the blood and then excreted in urine. Healthy kidneys filter creatinine which otherwise would increase in the blood.
As a result, blood creatine levels are used as a proxy of kidney function. The issue here is that creatinine levels in the blood is directly related to muscle mass and dietary intakes of creatine. With greater muscle mass comes greater levels of blood creatinine and further increases are apparent with supplementation. Therefore, with supplementation of creatine, blood creatinine and urine creatinine levels can increase. It is thought that this higher-than-normal level of creatinine excretion would place added stress to the kidneys and cause damage.
The reality however is that these transient increases in creatinine levels due to supplementation are unlikely to pose a risk in healthy individuals. Research has time and time again showed no ill effects with creatine supplementation on renal function. The exception to this was in one study where one participant had an already failing renal function and was advised to discontinue supplementation.
This is likely to be the origin of the purported negative effect on renal function with supplementation. Healthy individuals can supplement with creatine without adverse effects as shown in the research to date (Persky et al., 2007; De Souza et l., 2019; Gualano et al, 2011; Gualano et al., 2012).
Does creatine cause hair loss?
The idea that hair loss may occur with creatine supplementation stems from a study by Van De Merwe et al. where a large increase in serum dihydrotestosterone (DHT) was experienced over time with creatine supplementation. DHT has been linked to some occurrences of baldness, but not all. DHT binds to androgen receptors in weak hair follicles and causes hair loss.
The results from this study have not been replicated and thus it is very difficult to draw a clear conclusion on the findings. Research on creatine and free testosterone levels far have found no increases in testosterone. Testosterone is used to produce DHT. The research by Van De Merwe likely had other confounding variables at play and/or flaws in the research model. The great news lies in the fact that these results have not been replicated, indicating that you have nothing to worry about when it comes to the link with creatine and baldness/hair loss.
Does creatine cause fat gain?
This claim is prevalent because of the common acute increase in body weight after the loading phase of creatine supplementation. This increase in body weight is often confused with fat mass accumulation, something that has been refuted by the literature (Volek, 2004; Hatfield, 2008; Gotshalk, 2002; Silva, 2007; Forbes 2017; Antonio, 2013). Creatine is an osmotically active substance and can increase intracellular water levels. The initial loading phase of 20g daily for 5 days can lead to acute weight gain of 1 to 3 kg but this is attributable to an increase in total body water retention.
Creatine is safe.
- Persky AM, Rawson ES. Safety of creatine supplementation. Subcell. Biochem. 2007;46:275–89.
- de Souza E Silva A; Pertille, A.; Reis Barbosa, C. G.; Aparecida de Oliveira Silva, J; de Jesus, D. V.; Ribeiro, A G S V; Baganha, R. J.; de Oliveira, J. J. Effects of Creatine Supplementation on Renal Function: A Systematic Review and Meta-Analysis. J. Ren. Nutr. 2019, 29, 480-489.
- Gualano B, de Salles Painelli V, Roschel H, Lugaresi R, Dorea E, Artioli GG, Lima FR, da Silva ME, Cunha MR, Seguro AC, Shimizu MH, Otaduy MC, Sapienza MT, da Costa Leite C, Bonfa E, Lancha Junior AH. Creatine supplementation does not impair kidney function in type 2 diabeticpatients: a randomized, double-blind, placebo-controlled, clinical trial. Eur. J. Appl. Physiol. 2011;111:749–56.
- Gualano B, Roschel H, Lancha AH, Brightbill CE, Rawson ES. In sickness and in health: the widespread application of creatine supplementation. Amino Acids. 2012;43:519–29.
- van der Merwe J, Brooks NE, Myburgh KH. Three weeks of creatine monohydrate supplementation affects dihydrotestosterone to testosterone ratio in college-aged rugby players. Clin. J. Sport Med. 2009;19:399–404.
- Volek JS, Ratamess NA, Rubin MR, Gomez AL, French DN, McGuigan MM, Scheett TP, Sharman MJ, Hakkinen K, Kraemer WJ. The effects of creatine supplementation on muscular performance and body composition responses to short-term resistance training overreaching. Eur. J. Appl. Physiol. 2004;91:628–37.
- BA, Hatfield DL, Fragala MS, Volek JS. Creatine supplementation improves muscular performance in older women. Eur. J. Appl. Physiol. 2008;102:223– 31.
- Gotshalk LA, Volek JS, Staron RS, Denegar CR, Hagerman FC, Kraemer WJ. Creatine supplementation improves muscular performance in older men. Med. Sci. Sports Exerc. 2002;34:537–43.
- Silva AJ, Machado Reis V, Guidetti L, Bessone Alves F, Mota P, Freitas J, Baldari C. Effect of creatine on swimming velocity, body composition and hydrodynamic variables. J. Sports Med. Phys. Fitness. 2007;47:58–64.
- Forbes SC, Sletten N, Durrer C, Myette-Cote E, Candow D, Little JP. Creatine Monohydrate Supplementation Does Not Augment Fitness, Performance, or Body Composition Adaptations in Response to Four Weeks of High-Intensity Interval Training in Young Females. Int. J. Sport Nutr. Exerc. Metab. 2017;27: 285–92.
- Antonio J, Ciccone V. The effects of pre versus post workout supplementation of creatine monohydrate on body composition and strength. J. Int. Soc. Sports Nutr. 2013;10:36–6 eCollection 2013.
- Becque MD, Lochmann JD, Melrose DR. Effects of oral creatine supplementation on muscular strength and body composition. Med. Sci. Sports Exerc. 2000;32:654–8.