Association between dietary fiber and endometrial cancer: a meta-analysis

To explore a potential relationship between dietary fiber consumption and risk of endometrial cancer (EC), eligible studies published up to 30 June 2018 were retrieved via computer searches and manual review of references. Random-effects models were used to calculate summary relative risk (RR) estimates based on contrasting high- and low-fiber intake values. Sensitivity analysis was conducted, and heterogeneity among study results was explored through stratified analyses by study design, geographic region, Newcastle-Ottawa Scale (NOS) score, impact factor, and adjustment for several confounders (age, body mass index, smoking, energy intake, and education). We extracted data from 16 studies (involving 6,563 cases). There was a significant association between dietary fiber intake and EC (RR = 0.86, 95% confidence interval [CI]: 0.78, 0.93). In stratified analysis, this trend was more pronounced in the case-control studies, and in studies conducted in the Americas and Asia. The relationship was further confirmed after adjusting for education level (RR = 0.74; 95% CI: 0.60, 0.88) and age (RR = 0.70; 95% CI: 0.57, 0.83), and NOS scores of 6 (RR = 0.81; 95% CI: 0.67, 0.95) and 7 (RR = 0.75; 95% CI: 0.62, 0.88). In conclusion, our meta-analysis revealed an inverse association between dietary fiber consumption and EC risk. Further efforts should be made to confirm these findings.