Creatine Monohydrate

Creatine monohydrate is the most thoroughly studied performance supplement in existence, and after decades of scrutiny, the science keeps holding up. It works by expanding the phosphocreatine pool in muscle cells, enabling faster ATP regeneration during high-intensity efforts — the energy currency your muscles burn through in the first few seconds of a sprint, a heavy lift, or a hard interval. A 2025 meta-analysis confirmed creatine produces significant muscle strength gains versus placebo, with effect sizes favoring both trained and untrained individuals. The brain connection is increasingly credible: a 2022 meta-analysis in Nutrition Reviews found creatine improved memory performance in healthy individuals, with the most robust effects in older adults. A comprehensive 2025 safety analysis of 685 clinical trials found no significant difference in side effect rates between creatine and placebo groups — a finding that should finally retire the kidney-damage mythology. Athletes, aging adults concerned with muscle mass and cognition, and anyone doing resistance training are the clearest beneficiaries. It causes water retention inside muscle cells (not subcutaneous bloat), and some experience minor GI discomfort at loading doses. The rare supplement where the hype turned out to be underselling it.

Also known as: Creatine, Creapure, Methylguanidinoacetic acid