Dietary Antioxidants and Breast Cancer Risk: Effect Modification by Family History

Since breast cancer in a first-degree relative has been shown with some consistency to be associated with breast cancer risk (1), it is possible that family history modifies the effects of other risk factors, with disease in women with a family history possibly resulting from a different etiologic pathway. Studies have indicated that risk associated with some reproductive factors varies significantly for women with and without a family history (2). Since antioxidants have been shown to have an inverse association with breast cancer risk (3), these factors may also vary in their effects for women with and without a family history of the disease.