Nutrient Patterns and Risk of Breast Cancer among Iranian Women: a Case- Control Study.

Objective: To explore the role of nutrient patterns in the etiology of breast cancer (BCa) among Iranian women. Methods: The study included 134 newly diagnosed cases of BCa and 267 hospitalized controls. A validated semi-quantitative food frequency questionnaire (FFQ) was used to assess dietary intake. Nutrient patterns were obtained using principal component analysis using Varimax rotation and logistic regression was performed to estimate breast cancer risk. Results: We identified 4 major nutrient patterns. First was high in consumption of vitamins B1, B2, B3, B5, B6, B9, C, magnesium, iron, carbohydrate, fiber, selenium, zinc, protein, potassium, and calcium. The second nutrient pattern included Vitamins B12, A and cholesterol, while the third featured vitamin D, EPA and DHA. The fourth was characterized by vitamin E, MUFA and saturated fatty acids. After adjusting for age, patterns 1 and 3 were associated with a lower risk of BCa (OR=0.51, 95% CI: 0.33- 0.80, P=0.003, OR=0.64, 95% CI: 0.42- 0.98, P= 0.04 respectively). However, after further adjustment for all confounders in multivariate analysis, the association remained significant only for pattern 1 (OR=0.52, 95% CI: 0.32- 0.82, P=0.006). Conclusion: Adherence to a nutrient pattern rich in vitamin B, minerals and fiber is associated with a lower risk of breast cancer.