Dietary Fat, Eicosanoids and Breast Cancer Risk

Abstract

Abstract : Epidemiological and animal studies associate high levels of dietary fat with increased risk of sex. hormone mediated cancer, such as breast cancer. A high intake of total fat and omega-6 fatty acids increases risk while omega-3 (n3) fatty acids are associated with risk reduction. Our proposal is testing the effect of dietary fat and fatty acids on sex hormone concentrations in post-menopausal women. The objectives are to evaluate 1)the effects of total fat and n3 intake on plasma and urinary sex hormone levels. 2) the relationship between plasma fatty acids and plasma and urinary sex hormones, and 3) the effects of total. fat and n3 on the association between sex hormone concentrations and urinary prostaglandin E2 (PGE2). We are performing a randomized, Latin square-designed controlled feeding study testing High Fat, Low Fat, and Low Fat + n3 diets, each of 8 week duration. In order to determine the estrogenic effects of the diets, sex hormone endpoints will be measured reflecting availability. metabolism and action. Plasma fatty acids fractions and urinary PGE2 will be measured to evaluate mechanistic effects. At present 139 women have been screened by telephone, 24 have been screened in the clinic, 24 have been enrolled in the trial. Sixteen subjects have completed all aspects of the trial. Preliminary data of the sex hormone samples for the first 10 subjects has resulted in 2 abstracts for presentation at the DOD 2008 Era of Hope meeting. No manuscripts have yet been generated.