"At the time FDA established nutrient specifications for infant formula, selenium was not recognized as an essential nutrient and was not one of the nutrients required by statute in infant formula," FDA said. However, the mineral "has subsequently been recognized as an essential nutrient."
Typically found in plant foods, selenium helps prevent cellular damage from chemicals known as free radicals, which are natural by-products of oxygen metabolism. The heart ailment Keshan disease has been linked to a deficiency of selenium, and too much of the mineral can lead to hair and nail loss, fatigue and a host of other symptoms.
The mineral has also been linked to reducing risks of prostate cancer and diabetes.
The agency is requiring the between 2 and 7 micrograms per 1,000 calories of the mineral, a level of which most infant formulas are already in compliance.
The FDA is collecting comments on the proposal for 75 days.