A Case-control Study on the Association of Fruit and Vegetable Consumption with Risk of Breast Cancer.

Background: Limited data are available linking dietary intake of fruit and vegetables to breast cancer, in particular among the Middle Eastern population. The present study was done to investigate the association of fruit and vegetable consumption with the risk of breast cancer in Iranian adult women.

Methods: Dietary intake of fruit and vegetables was assessed using a validated 106-item Willett-format semi-quantitative dish-based food frequency questionnaire. Logistic regression was used to determine the association between fruit and vegetable consumption and breast cancer. Women aged >30 years, residing in Isfahan, Iran from July 2013 to July 2015. Breast cancer was diagnosed during the maximum of the last 6 months by physical examination and mammography findings.

Results: Overall, data on 350 cases and 700 controls were analyzed. After controlling for potential confounders, participants with the highest dietary intake of fruits had higher odds of breast cancer than those with the lowest intake (odds ratio [OR]: 8.23; 95% confidence interval [CI]: 4.37-15.50), while those who consumed highest amounts of vegetables were less likely to have breast cancer than their counterparts (OR: 0.12; 95% CI: 0.06-0.24). Although no significant associations were found between dietary intakes of fruits and vegetables and risk of breast cancer in premenopausal women, significant positive association between fruit consumption and breast cancer (OR: 16.80; 95% CI: 7.80, 36.21; P < .001) was observed in postmenopausal women.

Conclusions: We found an inverse association between dietary intake of vegetables and breast cancer. Fruit consumption was significantly associated with greater odds of breast cancer in this study.