The community suggests that creatine, while effective, could lead to sleep disturbances (insomnia, light sleep), significant digestive discomfort (bloating, diarrhea), visible water retention (puffy face), and, more rarely, skin problems or hair loss.

noli's read

Science largely confirms the safety of creatine for the kidneys in healthy subjects, contradicting user concerns about kidney pain (meta-analysis, Journal of the International Society of Sports Nutrition). The mentioned digestive issues are a classic and documented side effect, often linked to massive ingestion in a single dose or the unnecessary loading phase; splitting the dose or skipping the loading phase generally resolves the problem (RCT, scientific review). The idea that creatine disrupts sleep remains largely anecdotal, with no solid clinical evidence in current literature to explain such a mechanism. Regarding water retention, it is real but intracellular (within the muscle), which contradicts the notion of systemic facial bloating, which is often due to other lifestyle factors. The link to hair loss is based on a single old and highly contested study (observational), which has never been successfully replicated. The community is deeply divided between those who experience no side effects and those who attribute various symptoms to the supplementation.

the sources

1. 1NIH Office of Dietary Supplements 2026
2. 2r/Supplements