Abstract
BACKGROUND: It has been shown that chronic inflammation is a significant factor in cancer development and progression. The current study aimed to investigate whether a higher score on the empirical dietary inflammatory pattern (EDIP), which indicates a more pro-inflammatory diet, is related to higher odds of breast cancer in Iranian women. METHODS: In the present case-control study, subjects in the case (n = 133) and control (n = 265) groups were chosen from the hospitals in Tehran, Iran. The cases consisted of women with newly diagnosed breast cancer, while the controls were selected from other parts of the same hospital and had no history of cancer or hormone therapy. Individuals whose reported energy intake deviated by three standard deviations above or below the mean energy intake of the population were excluded from the study. A reliable and valid semi-quantitative food frequency questionnaire was used to determine the participants' dietary intake. Additionally, the association between breast cancer and EDIP was evaluated by logistic regression analysis in both crude and adjusted models. RESULTS: The median scores of EDIP in the case and control groups were 0.65 and 0.61, respectively. The findings also indicated that, in the adjusted model, the odds of developing breast cancer significantly increased in the last tertile of EDIP compared to the first tertile (odds ratio (OR) = 1.859; 95% confidence interval (CI): 1.059-3.265; P = 0.031). Additionally, after adjusting for potential confounders, higher odds of breast cancer were observed in the last tertile of EDIP compared to the first tertile in postmenopausal women (OR = 2.516; 95% CI: 1.081-5.856; P = 0.033). CONCLUSIONS: The current study indicated that individuals with a higher pro-inflammatory diet score were more likely to develop breast cancer.