Possible side effects and contraindications of creatine

Despite its benefits, it’s important to know the most common possible side effects linked to creatine use and the situations where it might be a no-go.

Ever wondered if creatine is safe?

Creatine is one of the most studied sports supplements worldwide and is generally considered safe when taken at recommended doses.

Scientific studies have shown that regular creatine supplementation can boost sports performance and increase muscle mass without causing significant adverse effects in most people.

Possible side effects of taking creatine

Among the possible side effects reported from creatine are the following, but all have been clarified and clear creatine of being the culprit:

1 Water retention and weight gain

• Myth: The idea that creatine causes unwanted weight gain due to water retention doesn’t consider the type of weight gained.
• Reality: Creatine promotes water retention at the intracellular level, not subcutaneous, which is key to maximizing its benefits. This retention helps improve performance and training capacity, a plus for those aiming to increase muscle mass.

2 Muscle cramps and dehydration

• Myth: It’s been speculated that creatine might cause muscle cramps and dehydration.
• Reality: Recent research suggests these effects are more linked to individual factors like genetics, physical effort, and nervous system function. Staying properly hydrated while supplementing with creatine can help reduce these risks.

3 Gastrointestinal and digestion issues

• Myth: Some believe that taking large amounts of creatine, especially at the start of use, can cause gastrointestinal discomfort in some people.
• Reality: By following dosing recommendations, starting with a suggested daily dose and adjusting as needed, adverse symptoms can be avoided, allowing smooth integration of the supplement into your diet.

4 Hair loss

• Myth: Creatine is said to raise DHT levels and thus speed up hair loss.
• Reality: A randomized controlled trial with 45 men (5 g/day of creatine vs. placebo for 12 weeks) measured total testosterone, free testosterone, DHT, and hair follicle health (density, thickness, and anagen/telogen phases) using trichometry and FotoFinder. No significant differences were found between creatine and placebo in any hormonal or hair parameters (p > 0.05), providing strong evidence that creatine does not cause hair loss.

5 Kidney failure and liver damage

• Myth: The belief that creatine supplementation can cause kidney failure and liver damage is a concern among athletes and users.
• Reality: Scientific research has not shown a direct link between creatine and kidney failure or liver damage in healthy individuals. Those with preexisting conditions in these organs should avoid use or consult a doctor before taking it.

When creatine might backfire

We recommend avoiding creatine if you have any of these conditions:

Long-term effects of creatine

Studies have shown that creatine supplementation is safe long-term for healthy individuals, with no significant adverse effects on kidney or liver function.

Research in the Journal of the International Society of Sports Nutrition and other studies lasting up to 21 months confirm that creatine is not only safe but also improves strength and muscle mass.

These findings highlight creatine’s effectiveness in sports performance and muscle recovery, as long as recommended doses are followed and you consult nutrition experts for prolonged use to avoid any side effects.

How to reduce side effects when taking creatine

Here are some handy tips:

Wrapping up

Although generally safe for most, it’s crucial to follow proper guidelines and seek professional advice if needed, especially if you have preexisting medical conditions or take medications.

Adopting a balanced diet with regular training, along with a responsible approach to creatine supplementation, lets you enjoy its perks while keeping health and safety in check.

Related posts:

• What you need to know about creatine before starting to take it
• Effects of creatine in one month

References

1. Examine.com. (n.d.). Creatine: https://examine.com/supplements/creatine/
2. Lanhers, C., Pereira, B., Naughton, G., Trousselard, M., Lesage, F. X., & Dutheil, F. (2017). Creatine Supplementation and Upper Limb Strength Performance: A Systematic Review and Meta-Analysis. Sports Medicine, 47(1), 163-173. https://pubmed.ncbi.nlm.nih.gov/29138605/
3. Kreider, R. B., Kalman, D. S., Antonio, J., Ziegenfuss, T. N., Wildman, R., Collins, R., … & Lopez, H. L. (2017). International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation in exercise, sport, and medicine. Journal of the International Society of Sports Nutrition, 14(1), 1-18. from https://jissn.biomedcentral.com/articles/10.1186/s12970-017-0173-z
4. Buford, T. W., Kreider, R. B., Stout, J. R., Greenwood, M., Campbell, B., Spano, M., … & Antonio, J. (2007). International Society of Sports Nutrition position stand: creatine supplementation and exercise. Journal of the International Society of Sports Nutrition, 4(1), 1-8. from https://jissn.biomedcentral.com/articles/10.1186/1550-2783-4-6
5. Greenwood, M., Kreider, R.B., Melton, C., Rasmussen, C., Lancaster, S., Cantler, E., Milnor, P., & Almada, A. (2003). Long-term creatine supplementation does not significantly affect clinical markers of health in athletes. Journal of the International Society of Sports Nutrition, 1(2), 1-29. https://pubmed.ncbi.nlm.nih.gov/12701816/
6. Lak M, Forbes SC, Ashtary-Larky D, Dadkhahfar S, Robati RM, Nezakati F, Khajevandi M, Naseri S, Gerafiani A, Haghighat N, Antonio J, Tinsley GM. Does creatine cause hair loss? A 12-week randomized controlled trial. J Int Soc Sports Nutr. 2025 Sep;22(sup1):2495229. doi: 10.1080/15502783.2025.2495229. Epub 2025 Apr 23. PMID: 40265319; PMCID: PMC12020143. https://pubmed.ncbi.nlm.nih.gov/40265319/