Breast Cancer Risk and Dietary Factor: A Case-Control Study

ABSTRACT

PURPOSE: This study was performed to evaluate the effect of dietary factors on the risk of breast cancer in Korean women. METHODS: New histologically proven breast cancer cases (n=108) were selected at Hanyang and Soonchunhyang University Hospitals in Seoul. Controls (n=121) were selected from patients in the Departments of Plastic Surgery, General Surgery and Opthalmology at the same hospitals by frequency matching of age and menopausal status. Informations on demographic, reproductive, and dietary factors were collected by an interviewer. Food intake was assessed by using food frequency questionnaires. The association of dietary factors with breast cancer risk was analyzed using total nutrient intake and food intake based on menopausal status. The statistical analysis was done by using unconditional logistic regression after adjusting for age and other confounding factors. RESULTS: The results were as follows Breast cancer risk significantly decreased with consumption of the following nutrients fiber in postmenopausal women, vit C in postmenopausal and total women, and vit E in premenopausal women. However, neither total energy nor fat intake was associated with development of breast cancer. Grape and pepper intake in premenopausal women and kimchi intake in total women were significantly associated with decreasing risk of breast cancer. Overall consumption of vegetables and fruits was associated with decreased breast cancer risk. CONCLUSION: Consumption of vegetables and fruits showed a protective effect in breast cancer risk, but neither the intake of fat nor the intake of protein was associated with breast cancer risk in this study. These findings suggest that the consumption of vegetables, and fruits is a protective factor. Further studies with larger numbers of subjects should be conducted to evaluate the association between breast cancer risk and dietary factors.