Folate and Breast Cancer: Protector, Bystander, or Both?

Studies examining folate intake and breast cancer risk present a mixed and often conflicting picture, with some reporting a protective association, others finding no relationship, and a few suggesting a U-shaped effect where both low and high intakes may influence risk differently. This inconsistency likely reflects differences in baseline folate status, dietary versus supplemental sources, timing of exposure, alcohol consumption, genetic variability in folate metabolism, and breast cancer subtypes rather than true disagreement in biology. While folate supports DNA synthesis and genomic stability, pooled analyses generally show no statistically significant overall effect on breast cancer risk, indicating that folate is not a universal protective factor. The emerging view is that folate acts as a context-dependent modifier, where adequate intake may be beneficial, but excess intake, particularly through supplementation in already sufficient populations, does not guarantee added protection and may behave differently across disease stages. However the meta-analysis of this study did not confirm this relationship. Results were inconsistent, and the meta-analysis indicated no significant effect.

Source : https://pubmed.ncbi.nlm.nih.gov/41437765/