Dietary diversity score, alternative healthy eating index and odds of breast cancer

Previous studies have mainly focused on individual food groups and nutrients in relation to breast cancer and few studies have considered diet as a whole variable. The aim of this study was to examine the association of dietary diversity score (DDS) and alternative healthy eating index-2010 (AHEI-2010) with odds of breast cancer. In this case-control study, we enrolled 477 pathologically confirmed cases of breast cancer and 506 age-matched controls. Dietary assessment was done using a food frequency questionnaire. Dietary indices including DDS and AHEI-2010 were constructed according to standard methods. After controlling for potential confounders, we found a significant inverse association between DDS and odds of breast cancer; individuals in the highest tertile of DDS had 37% lower odds for having breast cancer compared with those in the lowest tertile (OR: 0.63, 95% CI: 0.42–0.95). Such a significant inverse association was also seen among post-menopausal women; such that after taking potential confounders into account, women in the top tertile of DDS score were 60% less likely to have breast cancer compared with those in the bottom tertile (OR: 0.40, 95% CI: 0.19–0.83). With regard to AHEI, we found no significant association between AHEI score and odds of breast cancer either before or after controlling for potential confounders. This association remained non-significant either in pre-menopausal or post-menopausal women. We found that adherence to a diet with high diversity was associated with decreased odds of breast cancer. However, no significant association was observed between AHEI and breast cancer.