IN women and men, creatine monohydrate appears safe when used appropriately with no proven cancer or kidney risk in healthy adults.
Creatine Safety in Women: What the Review Found
Creatine monohydrate is widely used in sport and clinical settings, yet questions persist about long-term safety, particularly for women who may be pregnant, have comorbidities, or use supplements intermittently. In this short narrative review, the authors examined the most common safety concerns tied to creatine ingestion: cancer risk, impaired kidney function, dehydration or muscle cramping, and gastrointestinal intolerance. Across these themes, the overall message was consistent: when creatine is used appropriately, the available evidence supports a favorable safety profile in healthy individuals. At the same time, the review emphasized important evidence gaps for specific populations, including pregnant women and those with pre-existing kidney conditions.
Cancer Risk: Theoretical Concerns, Limited Human Support
The review outlines why cancer concerns arise, including discussion of whether creatine could contribute to carcinogenic compound formation under certain conditions and whether creatine metabolism might influence tumor biology. However, the authors report that current human evidence does not substantiate a link between creatine supplementation and cancer. They also highlight that the broader scientific debate includes conflicting experimental signals across different models, which limits certainty about how creatine might behave in specific oncologic contexts.
Kidney, Hydration, and GI Tolerability
Kidney safety remains a central patient and clinician concern, particularly for women with prior renal disease or reduced renal reserve. The review reports that studies in healthy individuals consistently show no adverse effect of creatine on renal function, while advising caution for those with pre-existing kidney conditions because data are limited. Concerns that creatine triggers dehydration or muscle cramps during exercise were described as largely unsupported by controlled studies, with some evidence suggesting creatine may reduce cramping and help maintain thermoregulation. Gastrointestinal symptoms were noted to occur in some users, particularly at higher doses, and appeared to be dose-dependent rather than universal.
Reference: Longobardi I et al. A short review of the most common safety concerns regarding creatine ingestion. Frontiers in Nutrition. 2025;12:10.3389/fnut.2025.1682746.
