Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 3/28/2000
Publication Date: N/A
Technical Abstract: There is much interest in increasing the dietary intake of Se. We have conducted a series of studies determining how Se accumulates in foods and the health benefits (primarily colon cancer prevention) of that Se. We demonstrated that the concentration of Se in similar food products varies, probably depending on geographical origin of the raw agricultural products. Beef is a major source of dietary Se, and much of it comes from seleniferous areas of the Western U.S. Selenium concentrations in North Dakota beef varied from < 0.2 to > 2.0 ug/g, depending on soil and forage Se concentration. Diets enriched in Se from beef significantly improved mood in young men. Wheat also is grown in seleniferous areas and also is a major source of dietary Se. The anti-colon cancer benefits of high-Se wheat are being tested by feeding diets enriched in breakfast cereal made from high-Se wheat. Broccoli grown in selenized media accumulates high concentrations of Se as Se-methyl selenocysteine. Selenium from broccoli did not accumulate in some tissues, increase GSH-Px activity or induce GSH-Px mRNA in the liver (p=0.0001) as well as selenite. Hydroponically- grown broccoli was labeled with 74**Se and fed to young men. 74**Se from broccoli did not accumulate in the plasma as well as 74**Se from selenate. The colon cancer-prevention properties of Se from broccoli or broccoli sprouts was tested in rats injected with dimethyl hydrazine. Compared to diets that used equal amounts of Se as selenate or equal amounts of low-Se broccoli, Se from broccoli decreased the number of aberrant crypts significantly. These studies show that it is possible to take advantage of natural variations in environmental Se to produce raw and processed foods enriched in Se.