Submitted to: Journal of Federation of American Societies for Experimental Biology
Publication Type: Abstract Only
Publication Acceptance Date: December 2, 2002
Publication Date: March 14, 2003
Citation: Finley, J.W., Grusak, M.A., Keck, A., Gregoire, B.R. 2003. Bioavailability of selenium from meat and broccoli as determined by retention and distribution of se75 [abstract]. Journal of Federation of American Societies for Experimental Biology. 17(5):A1136. Technical Abstract: Meat is the single greatest source of selenium (Se) in the North American diet. Although not naturally enriched in Se, broccoli will accumulate Se when grown on high Se soils. Previous reports have demonstrated that Se from meat is highly bioavailable whereas Se from broccoli has poor bioavailability but is protective against colon and mammary cancers. To further elucidate differences in metabolism of Se from these foods, we have fed rats diets adequate (0.1 ug/g diet) or high (1.5 ug/g diet) in Se and then given them a test meal of intrinsically labeled Se75 meat or broccoli. When dietary Se was adequate, more Se75 was retained from meat than broccoli, but there were less differences in retention when dietary Se was high. In general, a greater percentage of Se75 from broccoli was excreted in the urine than from meat. Dietary Se did not affect the excretion of Se75 from broccoli into urine, but the excretion of Se75 from meat varied with dietary Se intake. Se75 derived from meat effectively labeled selenoproteins in all tissues examined, but Se75 from broccoli was undetectable in selenoproteins. These data suggest that a major portion of Se from meat and broccoli enter different metabolic pools within the body, and these different pools may account for the observed differences in bioavailability and cancer protection.