Eating Habits, Risk of Breast Cancer, and Diet-Dependent Quality of Life in Postmenopausal Women after Mastectomy

The present study examined dietary risk factors for breast cancer, their association with quality of life, and changes in eating habits in postmenopausal women after mastectomy. The study included 210 women with histologically confirmed invasive breast cancer and 225 women without a cancer diagnosis. Questionnaire data on frequency of intake of 40 different foods, the Block Food Frequency Questionnaire, and SF-36 for evaluation of quality of life were used. All questionnaire data in the patient group were collected after diagnosis. Questions about eating habits covered two time points—before breast cancer diagnosis and after completion of treatment. Logistic regression was applied to calculate the odds ratios of breast cancer risk and 95% confidence intervals. A significant positive association was found between the risk of breast cancer and more frequent intake of red meat, smoked products, offal, animal fat, white bread, potatoes, and sweets, high intake of total fat, and low consumption of dietary fibre. Foods that were inversely associated with the risk of breast cancer included fish, vegetables, fruit, wholemeal bread, and groats. The relationship between quality of life and dietary habits according to the Block Eating Frequency Questionnaire was analysed using multiple regression. It was shown that high intake of total fat reduces the quality of life in its mental components. We observed a positive change in eating habits after cancer diagnosis, albeit not always to the level in the control group. As an important lifestyle component, the diet is of great significance for primary prevention of breast cancer as well as for improving the quality of life of breast cancer patients.