Intervention Summary
High dietary fiber intake as a preventive strategy against ovarian cancer. This is the strongest epidemiological evidence for any dietary intervention in OC, with meta-analytic dose-response data from 13 studies and 142,189 participants.
Evidence
Meta-Analysis (Zheng 2018)
- Design: Systematic review and meta-analysis, 13 studies, 5,777 OC cases, 142,189 participants
- Primary outcome: Highest vs. lowest fiber intake: RR = 0.78 (95% CI: 0.70-0.88), no heterogeneity
- Dose-response: Each 10 g/day increase = 12% reduced OC risk (RR: 0.88)
- Source: [1]
Mechanism
Fiber targets the core ecological disruption in OC — SCFA depletion from loss of butyrate-producing genera:
- Prebiotic effect: Fermentable fiber feeds Coprococcus, Butyricicoccus, Oscillibacter, Fusicatenibacter — all significantly depleted in OC patients ([2], n=382)
- Butyrate production: Butyrate has direct anti-inflammatory and anti-tumor properties; identified as a causal protective factor by Mendelian randomization [3]
- Estrogen metabolism: Fiber may modulate estrobolome activity by altering the microbial community responsible for beta-glucuronidase production, reducing estrogen recirculation relevant to estrogen-dependent OC