Nutritional factors and breast cancer

In view of an increasing incidence of breast cancer, preventive research is of utmost importance. Breast cancer is a systemic disease caused by many f actors. Besides a generic predispositon, nutritional and environmental fact ors may be involved. Epidemiological and case control studies as well as in vitro investigations suggest anticancerogenic action especially of isoflav ones and lignans. Isoflavones are present mainly in soy products, lignans i n grains, vegetables, fruits and flax seeds. Phytoestrogens are assumed to influence the estrogen receptors. Their mode of action in breast cancer has not been verified. At present, supplementation of phytoestrogen is not adv iced. Phytoestrogens containing foods may be helpful.