A short review of the most common safety concerns regarding creatine ingestion.
Level 5 - mechanism / opinion, no new human data
Narrative review synthesizing existing literature without systematic methodology
PubMed 41404326 · doi:10.3389/fnut.2025.1682746
What was done
This short narrative review evaluated the current evidence regarding common safety concerns of creatine monohydrate ingestion, specifically focusing on cancer risk, renal function impairment, dehydration, muscle cramps, and gastrointestinal issues.
What was found
No quantitative data or effect sizes are provided in the abstract. Qualitatively, the evidence does not support an association with cancer, shows no adverse effects on renal function in healthy populations, and indicates no adverse effects on hydration or thermoregulation (potentially reducing muscle cramps). Gastrointestinal distress was noted to occur in some individuals in a dose-dependent manner.
Why it matters
It contextualizes common clinical and athletic concerns regarding creatine supplementation, distinguishing unsubstantiated theoretical risks from real, dose-dependent side effects.
Limits
The abstract reports no sample size or number of reviewed studies, lacks quantitative statistical outcomes, and notes a lack of safety evidence for pregnant women and individuals with pre-existing kidney disease.