Formula-fed infants often have lower serum selenium levels than breast-fed infants. Although no deleterious effects have been correlated to this finding, supplementation of formula with selenium is considered. In this study, we investigated the uptake and retention by suckling rat pups of 75Se from selenite, selenate, and selenomethionine added to infant formula. The molecular distribution of 75Se in liver, kidney, intestine, and plasma was followed by gel-filtration chromatography on Superose 12. 75Se-uptake was most rapid from selenomethionine (70% at 1 hr), followed by selenate (51%) and selenite (29%). This difference was explained by a higher retention of 75Se in the stomach and small intestinal wall of pups given selenite supplement. Plasma distribution of 75Se as studied by gel filtration was also different, with a higher proportion of 75Se from selenomethionine being protein-bound than from selenite or selenate. Similarly, a larger proportion of 75Se from selenomethionine became protein-bound in the liver than from selenite or selenate. In conclusion, although whole body retention after 24-48 hr was similar, the metabolic fate of selenium varies considerably with the form of selenium added to formula. Further studies are needed to study the long-term consequences of selenium accumulated in different body compartments.
- infant formula
- selenium retention
- selenium supplementation
ASJC Scopus subject areas
- Endocrinology, Diabetes and Metabolism