Association between Healthy Eating Index-2015 and Breast Cancer Risk: A Case-Control Study

OBJECTIVE: Diet quality is known to influence cancer risk. The Healthy Eating Index (HEI) is one of the most frequently used measures of diet quality. However, the association between HEI-2015 and breast cancer risk is not known. The present study was undertaken to evaluate the association between HEI-2015 and breast cancer risk. METHODS: A case-control study comprising 134 breast cancer patients and 265 cancer-free controls were conducted. Dietary intakes were assessed using a validated food frequency questionnaire (FFQ), from which the HEI-2015 score was calculated. Logistic regression was used to derive the odds ratios (ORs) for measuring the association between HEI-2015 scores and breast cancer risk. RESULTS: Subjects in the top quartile of HEI-2015 had a 46% lower chance of breast cancer compared with subjects in the bottom quartile (OR 0.54; 95% CI 0.30, 0.98). After adjustment for potential confounders such as age, age at menarche, oral contraceptive drug use, menopausal status, marital status, body mass index, smoking and education level, the association between HEI-2015 score and a lower risk of breast cancer was enhanced (OR 0.32; 95% CI 0.16, 0.65). CONCLUSION: We successfully demonstrated that a higher HEI-2015 score was associated with a reduced breast cancer risk.