RESUMEN
Although breast cancer is the most common form of cancer in women worldwide, only a few investigations have addressed the role of dietary patterns. Our main objective, was to identify the relationship of major dietary patterns and breast cancer. In this case-control study, 100 patients, 30-65 years old, with breast cancer, and 174 controls from the Shohada hospital in Tehran, were sampled. Dietary intake was measured with a food frequency questionnaire. Physical activity, demographic factors and health status were questioned. The questionnaires were completed by an interviewers. Factor analysis was used to identify major dietary patterns. The association between major dietary patterns and breast cancer risk were examined by logistic regression analysis. Two dietary patterns were identified. The healthy food pattern was characterized by the consumption of vegetables, fruits, low fat dairy, legumes, olive and liquid oils, Condiments, fish, organic meat, poultry, pickles, soya, and whole grains and the unhealthy food pattern was characterized by consumption of colas, sugar, tea, coffee, potato chips, fried potatoes, salt, sweets, desserts, hydrogenated fats, nuts, commercial fruit juice, refined grains, and red and processed meat. After adjusting for potential confounding variables, women in the highest tertile of the healthy dietary pattern scores, had a 66% decreased risk of breast cancer compared to those in the lowest [OR: 0.34 CI: 0.11-1.05]; the unhealthy dietary pattern significantly increased the risk of breast cancer [OR: 5.17 CI: 1.56-17.14]. The healthy dietary pattern was inversely, and the unhealthy dietary pattern was directly associated with breast cancer risk