Causal assessment of 187 dietary habits with ovarian cancer from multiple sources via Mendelian randomization and meta-analysis

Observational studies have suggested that dietary habits may influence ovarian cancer risk, but Mendelian randomization (MR) evidence remains limited. Genetic data for 187 dietary habit phenotypes and ovarian cancer were collected and preprocessed. MR analyses were performed using 2 independent ovarian cancer datasets. Inverse-variance weighted estimates were pooled by meta-analysis, and multiple-testing correction was applied. Reverse MR analyses were conducted for significant dietary phenotypes to assess causal direction. Among the 187 dietary habit phenotypes, only cherry preference (GCST90094731) showed a significant causal association with ovarian cancer risk. In the FinnGen R12 dataset, the inverse-variance weighted estimate was not significant (odds ratio [OR] = 0.902, 95% confidence interval [CI]: 0.703-1.158; P = .419). In the OpenGWAS dataset, cherry preference was associated with reduced ovarian cancer risk (OR = 0.809, 95% CI: 0.691-0.948; P = .0087). Meta-analysis yielded a combined OR of 0.835 (95% CI: 0.730-0.954; P = .0081), and the association remained significant after Bonferroni correction. Reverse MR analysis showed no evidence of reverse causality. Genetically predicted cherry preference was associated with a lower risk of ovarian cancer. These findings provide genetic evidence supporting a potential role of dietary habits in ovarian cancer prevention and may inform precision nutrition and public health strategies.