Numerous university health publications, including the Harvard Health Letter, report the health benefits and the safety of vitamin E. The Harvard publication recently reviewed developments on Vitamin E and reported: "Having vitamin E in your blood is like having a cop on the beat. It is an antioxidant, rounding up the by-products of normal metabolism called 'free radicals,' reactive molecules that damage DNA and cell membranes and encourage plaque build-up in the arteries. "Several large studies that followed participants over several years have suggested that vitamin E supplements protect against heart disease. Because of its antioxidant properties, it has also been promoted as an anticancer agent." According to the Harvard Health Letter, vitamin E "may also help keep your brain healthy," citing a study finding that Vitamin E in supplement form slowed the progression of Alzheimer's disease in people in the middle stages of the condition. The publication noted conflicting studies regarding vitamin E supplementation, however, said that "anticancer findings have been less convincing than the cardiovascular studies." However, recently the National Cancer Institute announced that it will test whether taking vitamin E and the mineral selenium together or separately might "be an effective way to prevent prostate cancer."