Selenium, Cancer, and Type 2 Diabetes Mellitus
In a review of studies investigating the relationship between selenium, cancer, and type 2 diabetes mellitus, the authors review the results of various studies. In the Selenium and Vitamin E Cancer Prevention Trial, the authors found that selenium supplementation did not prevent the development of prostate cancer and the incidence of newly diagnosed type 2 diabetes mellitus.
In the Nutritional Prevention of Cancer trial, 200 microg/d selenium for 7.7 years was associated with a reduced risk of prostate cancer, however, this same trial showed an increased risk of type 2 diabetes mellitus among subjects in the top tertile of plasma selenium levels. The authors state, "Further studies are required to elucidate the relationship between selenium and adipocytokines and the role of selenoprotein P in the development of type 2 diabetes mellitus and cancer at high levels of selenium."