Is vitamin D2 (ergocalciferol) present in food?

Vitamin D2 in Food Sources

Yes, vitamin D2 (ergocalciferol) is present in certain foods, primarily in plant-derived sources, while vitamin D3 (cholecalciferol) is more commonly found in animal-derived foods.

Natural Sources of Vitamin D2

Vitamin D2 is naturally found in:

• Mushrooms: Wild mushrooms and UV-exposed cultivated mushrooms are excellent sources of vitamin D2 1, 2

  • When mushrooms are exposed to UV light (either sunlight or artificial UV lamps), they convert their ergosterol content to vitamin D2
  • UV-exposed mushrooms can contain up to 18 μg of vitamin D2 per 75g serving, which exceeds the daily recommended intake of 10 μg 2

• Plant-derived foods: Vitamin D2 is primarily found in plant sources 3

  • Ergocalciferol (D2) is the plant-derived form of vitamin D

Vitamin D2 vs. Vitamin D3 in Foods

• Animal sources: Vitamin D3 is the predominant form in animal-derived foods such as eggs, fish, liver, and marine mammal fat 3

  • A cup of milk provides about 100 IU of vitamin D3
  • A serving of salmon contains approximately 400 IU of vitamin D3

• Supplements: While dietary sources may contain either D2 or D3, supplements typically contain the plant-derived form, ergocalciferol (D2) 3

Bioavailability and Metabolism

• Both vitamin D2 and D3 undergo similar metabolic pathways in the body, requiring two sequential hydroxylation steps to become active 3
• There are some differences in metabolism between D2 and D3:
  • Vitamin D3 may be more effective at raising and maintaining 25(OH)D levels over longer periods when using longer dosing intervals 3
  • With daily dosing, no significant difference was found in maintaining vitamin D levels between D2 and D3 3

Practical Considerations

• Limited natural sources: Vitamin D is naturally present in very few foods, which is why it's often added as a supplement to food products 3
• UV-exposed mushrooms: These represent a promising food-based solution to vitamin D deficiency 2
  • Four servings per week of UV-exposed button mushrooms can help meet vitamin D recommendations 2
  • The vitamin D2 in UV-exposed mushrooms shows good stability during cooking and processing 2

Common Pitfalls to Avoid

1. Overlooking mushrooms as a vitamin D source: Dietary guidelines often fail to recognize UV-exposed mushrooms as a significant source of vitamin D2 2

2. Assuming all mushrooms contain vitamin D2: Only mushrooms exposed to UV light (either sunlight or artificial UV) contain significant amounts of vitamin D2; those grown in the dark have minimal vitamin D content 1

3. Confusing vitamin D forms: Remember that D2 (ergocalciferol) is plant-derived, while D3 (cholecalciferol) is primarily found in animal sources and produced in human skin through sun exposure 3

In summary, while vitamin D2 is not abundant in most common foods, it is naturally present in UV-exposed mushrooms and is commonly used in supplements and food fortification.