Creatine monohydrate is the most rigorously researched and consistently effective sports supplement in existence. This isn't a marketing claim — it's the position of the International Society of Sports Nutrition (ISSN), reaffirmed in their updated position stand in 2025 (Kreider et al., 2025). Yet despite decades of research, myths persist about kidney danger, the need for loading phases, and the superiority of expensive alternative forms.
How creatine works
Creatine is a naturally occurring compound in the body — primarily in skeletal muscle (~95%), with the remainder in the brain, liver, and kidneys. The body synthesizes it from amino acids (arginine, glycine, methionine) at ~1 g/day, and we obtain additional amounts from food — mainly red meat and fish (Kreider et al., 2025).
During short-duration, high-intensity activity (lifts, sprints, jumps), the body uses phosphocreatine (PCr) to rapidly regenerate ATP — the cell's primary energy currency. When PCr stores are depleted, performance drops. Creatine supplementation increases intramuscular PCr concentration by 20–40%, meaning: more energy for more reps, longer high-intensity work, and faster recovery between sets (Antonio et al., 2025).
What does science say about strength and muscle mass?
A meta-analysis by Zhang et al. (2025, PeerJ) reviewed RCTs and confirmed that creatine combined with resistance training significantly increases muscle strength. The effect was more pronounced with high-intensity training (above 75% 1RM) and in younger populations.
Wang et al. (2024, Nutrients) in a meta-analysis of 23 studies in adults under 50 found that creatine with resistance training significantly increased both upper-body strength (+4.43 kg) and lower-body strength versus placebo. The effect was greater in males than females.
Liu et al. (2025, European Review of Aging and Physical Activity) in a meta-analysis of 20 RCTs with 1,093 participants over 55 confirmed that creatine with exercise significantly increases strength (1RM) even in older adults — a key finding for combating sarcopenia.
Creatine and the brain
Creatine isn't just a "muscle" supplement. Roschel et al. (2023, Nutrients) showed in a literature review that creatine supplementation improves short-term memory and cognitive performance, especially under conditions of stress, sleep deprivation, or aging. The brain is metabolically highly active and uses phosphocreatine the same way muscles do — for rapid ATP regeneration.
Dosing and form
ISSN recommendation (Kreider et al., 2025): 3–5 g of creatine monohydrate daily, with no need for a loading phase. Loading (20 g/day for 5–7 days) speeds saturation but isn't necessary — regular daily use achieves the same effect in 3–4 weeks. Antonio et al. (2025) in "Common questions and misconceptions" confirm that creatine monohydrate remains the most effective and safest form — more expensive alternatives (kre-alkalyn, HCl, ethyl ester) have no proven advantage.
Pashayee-Khamene et al. (2024, Journal of the International Society of Sports Nutrition) confirmed in a GRADE-assessed meta-analysis a dose-dependent effect of creatine on body composition — but with diminishing returns above 5 g/day.
Safety
Antonio et al. (2024) concluded in a comprehensive long-term safety review that there is no evidence of harmful effects on kidneys, liver, or the cardiovascular system in healthy individuals — even with use exceeding 5 years. The kidney damage myth stems from misinterpretation of elevated creatinine (a byproduct of creatine metabolism filtered through the kidneys — not an indicator of damage).
References
- Antonio, J. et al. (2024). Long-term safety of creatine supplementation: a comprehensive review. Journal of the International Society of Sports Nutrition, 21(1), 2341.
- Antonio, J. et al. (2025). Common questions and misconceptions about creatine supplementation: what does the scientific evidence really show? Part II. Journal of the International Society of Sports Nutrition, 22, 2441760.
- Kreider, R.B. et al. (2025). ISSN position stand: safety and efficacy of creatine supplementation (updated). Journal of the International Society of Sports Nutrition, 22(1).
- Liu, S. et al. (2025). The impact of creatine supplementation associated with resistance training on muscular strength and lean tissue mass in the aged: systematic review and meta-analysis. European Review of Aging and Physical Activity, 22, 26.
- Pashayee-Khamene, F. et al. (2024). Creatine supplementation protocols with or without training interventions on body composition: a GRADE-assessed systematic review and dose-response meta-analysis. Journal of the International Society of Sports Nutrition, 21, 2380058.
- Roschel, H. et al. (2023). Creatine supplementation and brain health. Nutrients, 15(2), 378.
- Wang, Z. et al. (2024). Effects of creatine supplementation and resistance training on muscle strength gains in adults <50 years: systematic review and meta-analysis. Nutrients, 16(21), 3665.
- Zhang, H. et al. (2025). Effects of creatine supplementation on muscle strength gains — a meta-analysis and systematic review. PeerJ, 13, e20380.
Important notice
This article is for informational and educational purposes only. It does not constitute medical advice, diagnosis, or treatment, and is not a substitute for professional medical consultation.
All decisions regarding health, nutrition, exercise, or lifestyle changes should always be discussed with your physician, who understands your complete medical history.
The author is not a medical doctor and assumes no liability for any consequences arising from the use of this information without medical supervision.