US FDA Approves New Source of Vitamin D₂ for Food Fortification

The US Food and Drug Administration (FDA) has amended its food additive regulations to permit the use of vitamin D₂ inactive bakers yeast as a source of vitamin D₂ in a range of food categories. The final order became effective on 25 September 2026 and provides manufacturers with an additional option for vitamin D fortification.

Vitamin D₂ inactive bakers yeast is produced by exposing baker’s yeast (Saccharomyces cerevisiae) to ultraviolet (UV) light, which converts naturally occurring ergosterol into vitamin D₂. The yeast is subsequently inactivated through heat treatment before being incorporated into foods. The newly authorised uses mirror those already permitted for vitamin D₂ mushroom powder, allowing the ingredient to be used in a variety of fortified food product.

In its safety assessment, the FDA concluded that the ingredient would not increase overall dietary exposure to vitamin D because its intended uses are substitutional rather than additive. The agency also found that the UV treatment process does not generate compounds of toxicological concern and that estimated vitamin D intakes remain below established tolerable upper intake levels across all population groups.

Stakeholders wishing to challenge the decision may submit electronic or written objections and requests for a hearing by 26 October 2026.