What are vegan sources of vitamin D2?

November 17, 2025 •

4 min read

Globally, an estimated one billion people have insufficient levels of vitamin D, making careful dietary planning essential for everyone, especially those on a plant-based diet. Knowing what are vegan sources of vitamin D2 is a key step for vegans to support bone health and immune function through diet and supplementation.

Quick Summary

Primary vegan sources of vitamin D2 include UV-exposed mushrooms and a range of fortified plant-based products like milks, cereals, and orange juice. Supplements provide a reliable alternative for consistent intake.

Key Points

Mushrooms are the only natural vegan food source: When exposed to UV light or direct sunlight, mushrooms, particularly shiitake and portobello, convert ergosterol into vitamin D2.
Fortified foods provide consistent D2: Many plant-based milks, cereals, and orange juices are fortified with vitamin D2, offering a reliable dietary source.
Check nutrition labels for fortification: Always read the product label to ensure it contains added vitamin D and is suitable for vegans.
Enhance absorption with fat: Since vitamin D is fat-soluble, consuming fortified foods or supplements with a source of fat can improve your body's absorption.
Consider D2 or vegan D3 supplements: For consistent and sufficient intake, particularly in winter, vegan D2 or lichen-sourced vegan D3 supplements are a reliable choice.
Sunlight is a factor, but not always sufficient: Limited, safe sun exposure helps with vitamin D production, but for many, it is not enough to meet daily requirements.

Vitamin D is an essential fat-soluble nutrient that plays a crucial role in regulating calcium and phosphate levels, which are vital for maintaining healthy bones, teeth, and muscles. While many people rely on sunlight or animal products for their vitamin D, those following a vegan lifestyle must seek alternative plant-based or fortified sources. Ergocalciferol, or vitamin D2, is the form derived from fungi and plants, making it a naturally vegan option.

UV-Exposed Mushrooms: The Natural Vegan Source

Mushrooms are the only widely available natural vegan food source of vitamin D. This is because they contain a compound called ergosterol, which converts into vitamin D2 when exposed to ultraviolet (UV) light. However, the vitamin D content can vary significantly, as most commercially grown mushrooms are cultivated in dark conditions with little to no UV exposure.

How to naturally increase vitamin D in mushrooms

You can easily boost the vitamin D content of store-bought mushrooms at home. By simply exposing fresh, sliced mushrooms to direct midday sunlight for a short period, they can generate a significant amount of the vitamin. For example, a half-cup of raw white mushrooms can contain a substantial portion of the daily recommended intake after UV exposure.

Here are some tips for maximizing vitamin D absorption:

Choose the right variety: Shiitake, maitake, and portobello mushrooms respond well to UV light exposure.
Maximize surface area: Slice the mushrooms and lay them gill-side up on a baking sheet to expose more surface area to the sun.
Combine with fat: Since vitamin D is fat-soluble, cooking your sun-treated mushrooms with a bit of healthy oil can further enhance absorption.

Fortified Foods: The Convenient Way

For many vegans, the most reliable and consistent way to get vitamin D2 from their diet is through fortified foods. Manufacturers add ergocalciferol to a variety of plant-based products to help consumers meet their nutritional needs. The key is to always check the product label to ensure it is fortified and to determine if it contains vitamin D2 or a vegan-friendly D3.

Common fortified vegan foods

Plant-Based Milks: Soy, almond, oat, and rice milks are often fortified with vitamin D2 and calcium, providing a simple way to increase daily intake.
Breakfast Cereals: Many mainstream breakfast cereals are fortified with vitamins, including vitamin D. Look for brands that specify the use of D2 or a vegan-friendly D3.
Orange Juice: Select brands of orange juice are fortified with vitamin D and calcium, making them a convenient option.
Vegan Yogurts and Spreads: Fortified plant-based yogurts and margarine can also contribute to your vitamin D intake.

Vitamin D2 vs. D3 for Vegans

While this article focuses on D2, it is important to understand its comparison to vitamin D3. Historically, D3 was not considered vegan as it was sourced from lanolin (sheep's wool). However, vegan-friendly D3 is now widely available, derived from lichen or algae. Some research suggests D3 may be more effective at raising blood vitamin D levels than D2, though both are well-absorbed. For vegans, the choice often comes down to availability and personal preference, as both are effective options.

D2 vs. D3: A quick comparison


Feature	Vitamin D2 (Ergocalciferol)	Vitamin D3 (Cholecalciferol)
Vegan Source	Fungi (mushrooms, yeast) exposed to UV light	Lichen or algae-derived D3, or sunlight exposure
Effectiveness	Effectively increases vitamin D levels and can treat deficiency	Generally considered more effective at raising and maintaining levels
Food Sources	UV-exposed mushrooms, fortified plant milks, cereals, orange juice	Fortified vegan foods that specify lichen-derived D3
Supplements	Readily available and always vegan	Available in vegan-specific formulations (check label)

Supplementation as a Key Strategy

Since it can be difficult to meet all vitamin D needs through diet alone, especially in regions with limited sunlight or during winter months, supplementation is often recommended for vegans. Both vitamin D2 and vegan-sourced vitamin D3 supplements are readily available in various forms, including tablets, capsules, and liquids. Consulting with a healthcare professional can help you determine the appropriate dosage for your needs, as taking excessive amounts can be toxic.

Conclusion: Strategic Intake of Vegan Vitamin D2

Maintaining adequate vitamin D levels is possible and achievable on a vegan diet through a combination of thoughtful food choices and, if necessary, strategic supplementation. By incorporating UV-exposed mushrooms and a variety of fortified plant-based products, you can significantly boost your intake of vitamin D2. For those seeking maximum absorption efficiency, exploring the newer vegan D3 supplements derived from lichen is also a viable option. Combining these dietary approaches with safe sun exposure, where possible, provides a robust strategy for supporting your overall health and well-being while adhering to a plant-based lifestyle.

For more detailed nutritional guidance and to understand the different forms of vitamin D, it's beneficial to consult reputable health resources and professionals. National Institutes of Health (NIH)

Frequently Asked Questions

Shiitake, maitake, and portobello mushrooms naturally contain ergosterol, which converts to vitamin D2 when exposed to UV light. Many grocery stores now carry UV-treated mushrooms with enhanced vitamin D content.

No, not all fortified foods are vegan. Some products may be fortified with animal-derived vitamin D3 or other non-vegan ingredients. It's important to check the ingredients list and look for explicit 'vegan' labeling.

While both vitamin D2 and D3 effectively raise vitamin D levels in the blood, some evidence suggests that D3 may be slightly more potent at increasing and maintaining these levels over time. However, for most people, either form is acceptable.

It can be challenging to obtain enough vitamin D from diet and sun exposure alone. Supplementation is often recommended for vegans, especially during seasons with less sunlight.

You must check the nutrition facts label on the carton. The label will list vitamin D content, typically in micrograms (mcg) or International Units (IU) per serving.

Fortified vegan foods can contain either D2 or vegan D3. D2 is always plant-based (from yeast or fungi), while vegan D3 is specifically sourced from lichen or microalgae. Always check the ingredient list to be sure.

While sunlight is a major source of vitamin D, factors like skin tone, location, season, and sun protection limit its effectiveness. Relying solely on the sun is not a consistent strategy for meeting dietary needs, particularly for vegans.