Vitamin D-2

Vitamin D-2, chemically known as ergocalciferol, is one of two major forms of vitamin D used in food fortification and supplementation. With CAS number 50-14-6, it is produced through ultraviolet irradiation of ergosterol, a sterol naturally found in fungi, yeast, and plants. Unlike vitamin D-3 (cholecalciferol), which is derived from animal sources, vitamin D-2 is often preferred in vegan and vegetarian food products and is the form typically used in pharmaceutical supplements in many countries.

Vitamin D-2 is extensively used in food fortification programs worldwide. It is commonly added to milk and dairy alternatives, breakfast cereals, orange juice, bread, and margarine. The nutrient is also found in mushrooms that have been exposed to sunlight or UV light. Vitamin D-2 serves as a nutrient supplement to help populations meet their daily dietary requirements, particularly in regions with limited sunlight exposure or where dietary sources of vitamin D are scarce. It is recognized as an essential micronutrient for maintaining bone health, supporting calcium absorption, and contributing to immune and muscle function.

Vitamin D-2 has been extensively studied and used in food fortification for decades. The FDA has not formally granted it GRAS (Generally Recognized As Safe) status, though this reflects regulatory classification rather than safety concerns—many nutrients and food ingredients operate under long-standing food standards rather than GRAS notices. The European Food Safety Authority (EFSA) has established Tolerable Upper Intake Levels (ULs) for vitamin D, with the consensus being that intakes up to 100 micrograms (4,000 IU) per day are safe for adults, though individual requirements vary by age and health status.

According to FDA records, there have been zero reported adverse events and zero recalls associated with vitamin D-2 as a food additive. Excessive vitamin D intake from supplementation (not from food fortification alone) can theoretically cause hypercalcemia and kidney issues, but this requires sustained intakes well above recommended levels and is not a concern with normal food consumption and fortification practices.

Vitamin D-2 is bioavailable in the human body, though some research suggests vitamin D-3 may be slightly more effective at raising serum 25-hydroxyvitamin D levels. Both forms are accepted and used in fortification programs by health authorities globally.

Vitamin D-2 is approved for use as a nutrient supplement in food fortification by the FDA under the Code of Federal Regulations. It is permitted in a wide range of food categories with specified maximum levels. The European Union permits vitamin D-2 in fortified foods under Regulation (EC) No 1925/2006. In Canada, it is approved for addition to designated food categories. Most countries worldwide recognize both vitamin D-2 and D-3 as acceptable forms for food fortification to address public health vitamin D deficiency concerns.

Research comparing vitamin D-2 and D-3 bioavailability has shown both forms are absorbed and metabolized by the human body. A 2022 systematic review in the American Journal of Clinical Nutrition examined vitamin D fortification efficacy across populations. The National Institutes of Health and EFSA have published comprehensive assessments of vitamin D intake and safety thresholds. Long-term fortification programs in countries like Canada and the United States have documented the safety and effectiveness of vitamin D-2 in preventing deficiency disorders.