Selenium in infant formula milk.

Formula-based animal milk is an alternative source of infant nutrition in many cases when breastfeeding is unacceptable or inaccessible; however, these replacements often have low selenium levels. The composition of infant formula milk should be as close as possible to that of human breast milk, both in content and chemical speciation. Selenium is an essential trace element for infants. Generally, human breast milk is the ideal food to ensure adequate infant Se intake. However, to date, sodium selenite or sodium selenate has been used as selenium supplementation in infant formula milk in most countries. This inorganic Se, which is not a natural component of food, may not be the optimal speciation for Se supplementation in infant formula milk. Advances in speciation in foods, especially in animal milk, suggest that future proposals for selenium speciation in human breast milk can lead to discussions regarding the most favorable methods of selenium supplementation in infant formula milk.