Selenium content of commercial formula diets

Fluorometric analyses for selenium (Se) content were done on infant formulas, formulas for tube feeding, food supplements, chemically defined diets, and total parenteral nutrition solutions. The Se content of products depended on the protein source. On a dry weight basis, the chemically defined diets which contained egg albumin had the greatest Se concentration (0.292 to 0.620 µ g Se/g), followed by the infant formulas and tube feeding formulas that contained meat (0.205 to 0.265 µ g Se/g). Somewhat lower values (0.041 to 0.178 µ g Se/g) were found in: 1) soy-, milk-, and casein-based infant formulas; 2) soy- and/or milk- and/or casein-containing food supplements or tube feeding formulas; and, 3) the chemically defined diet and the total parenteral nutrition product based on casein hydrolysate. The lowest Se concentrations (<0.005 µ g Se/g) were present in the chemically defined diets and total parenteral nutrition products that contained amino acid mixtures. Assuming daily caloric intakes of 700 kcal for infants, 2000 kcal for adult women, and 2700 kcal for adult men, an infant would receive 5 to 35 µ g Se/day, an adult woman would receive <1 to 294 µ g Se/day, and an adult man would receive <2 to 397 µ g Se/day, depending on the formula prescribed. Fourteen of the 16 analyzed infant formulas would provide less Se/day than an equivalent amount of typical breast milk (U.S.). Only three of the twenty analyzed formulas designed for adult use would provide an amount of Se similar to that consumed in a typical U.S. diet.