Discover What Plant Has the Most Vitamin D? Exploring Mushrooms, Lichen, and Fortified Foods

October 6, 2025 •

4 min read

An estimated one billion people worldwide are vitamin D deficient, highlighting the importance of understanding all potential dietary sources of this crucial nutrient. While sunlight remains the primary source, finding out what plant has the most vitamin D is vital for those with limited sunlight access or who follow a plant-based diet. Fortunately, a few non-animal sources can provide a significant boost.

Quick Summary

Mushrooms, particularly those exposed to UV light, are the most potent natural plant-based sources of vitamin D2. Other options include lichen, which can provide vegan vitamin D3, and a variety of fortified foods like plant milks and cereals.

Key Points

UV-Exposed Mushrooms Reign Supreme: Mushrooms that have been exposed to ultraviolet (UV) light, either from the sun or special lamps, are the richest natural plant source of vitamin D2, with some varieties offering hundreds of IU per serving.
Lichen Offers Vegan Vitamin D3: A rare and valuable source of vegan vitamin D3 (cholecalciferol), lichen can be found in supplements, making it an excellent option for those seeking the more bioavailable form.
Fortified Foods Provide Daily Boosts: Many plant-based milks, cereals, and some tofu and yogurts are fortified with vitamin D, offering a consistent and convenient way to increase your daily intake.
Maximize Absorption with Fat: As vitamin D is fat-soluble, consuming it with healthy fats from foods like avocado, nuts, or seeds can significantly enhance your body's absorption of the vitamin.
Consider Your Cooking Method: Studies suggest that cooking methods like pan-frying retain more vitamin D in mushrooms than boiling, so choose your preparation wisely.
The Difference Between D2 and D3: Plants and fungi produce vitamin D2, while animals produce D3. While both can raise vitamin D levels, D3 may be slightly more effective for maintaining them, and lichen provides a vegan-friendly D3 option.

Unveiling the Plant-Based Contenders for Vitamin D

When we think of vitamin D, sources like sunlight, fish, and fortified milk often come to mind. For those following a plant-based diet, obtaining sufficient vitamin D can be a challenge, as it is not naturally present in significant amounts in most common fruits and vegetables. This is where certain fungi and other lesser-known sources shine, offering viable options for boosting your intake.

The Mighty Mushroom: A Natural Factory for Vitamin D2

Mushrooms are unequivocally the most notable natural plant-based source of vitamin D. They contain a compound called ergosterol, which is a precursor to vitamin D2. When exposed to ultraviolet (UV) light, whether from the sun or a UV lamp, this ergosterol is converted into ergocalciferol (vitamin D2).

While most commercially grown mushrooms are cultivated in the dark and have very low vitamin D levels, a simple process can unlock their potential. By placing sliced mushrooms in direct sunlight for just 15 to 120 minutes, their vitamin D2 content can increase dramatically. The amount produced depends on factors like sun intensity, duration, and surface area exposed. For instance, UV-exposed cremini mushrooms can contain as much as 1100 IU of vitamin D per cup, while wild maitake mushrooms can offer up to 562 IU per 50 grams.

Lichen: The Exclusive Vegan Source of Vitamin D3

While mushrooms primarily provide vitamin D2, a unique plant-like organism called lichen can provide vitamin D3, the form found in animals and often considered more bioavailable. Lichens are a symbiotic organism composed of both a fungus and an alga. The vitamin D3 extracted from lichens offers a purely vegetable alternative for vegans who prefer or need the D3 form. This makes it a popular ingredient in many high-quality vegan vitamin D3 supplements.

Fortified Foods: A Consistent Source in Your Daily Diet

For many, the most accessible source of plant-based vitamin D comes from fortified foods. These products have vitamin D added during processing, offering a reliable way to increase daily intake.

Plant-based milks: Soy, almond, and oat milks are commonly fortified with vitamin D, providing a consistent amount per cup.
Fortified cereals: Many breakfast cereals include vitamin D as part of their nutritional profile.
Tofu and plant-based yogurts: Some varieties are fortified, offering an extra dose of the sunshine vitamin.
Fortified orange juice: Certain brands of orange juice also contain added vitamin D.

It is important to check the nutrition labels on these products, as fortification levels can vary. For those on a vegan diet, ensuring the vitamin D used for fortification is plant-based (often D2 or lichen-derived D3) is also a good practice.

Comparison of Plant-Based Vitamin D Sources


Source	Vitamin D Type	Typical Serving Size	Estimated IU	Notes
UV-exposed Mushrooms	D2	1 cup, raw	600–700 IU	The most potent natural source, requires UV light.
Lichen (supplements)	D3	Varies (check label)	Potentially high	A vegan source of the more bioavailable D3.
Fortified Plant Milk	D2 or D3	1 cup (240 ml)	96–144 IU	Convenient, but check for fortification type.
Fortified Cereal	D2 or D3	1 serving	Varies, typically 40–100 IU	Quick and easy, read the nutritional information.

Enhancing Vitamin D Absorption

Since vitamin D is a fat-soluble vitamin, consuming it with a source of healthy fat can significantly increase its absorption. For mushrooms, cooking them lightly in a small amount of oil can help. If you take a supplement, pairing it with a meal containing fats like avocado, nuts, seeds, or olive oil can be beneficial.

The Power of Practical Application

Integrating these sources into a balanced diet can help address vitamin D inadequacy, especially during winter months or for those with limited sun exposure. For example, a morning smoothie with fortified plant milk and a midday stir-fry with UV-treated mushrooms could provide a substantial dietary dose. Regularly consuming these foods, combined with safe sun exposure when possible, can contribute significantly to overall health and well-being. By harnessing the power of mushrooms, lichen, and fortified foods, it is possible for anyone, regardless of dietary preferences, to meet their vitamin D needs effectively.

Conclusion: Making the Right Plant-Based Choices

For those seeking the plant with the most vitamin D, the answer lies in understanding the difference between naturally occurring and fortified sources. UV-exposed mushrooms, particularly varieties like cremini and maitake, are the leading natural contenders, offering impressive levels of vitamin D2. For a vegan-friendly source of vitamin D3, lichen-derived supplements provide an excellent alternative. By incorporating these options, along with fortified plant milks, cereals, and other products, a plant-based diet can provide a robust and healthy intake of this vital nutrient, supporting everything from bone health to immune function.

An extensive review discussing the potential of mushrooms as a dietary vitamin D source can be found in A Review of Mushrooms as a Potential Source of Dietary Vitamin D.

Frequently Asked Questions

UV-exposed white button, cremini, and maitake mushrooms are among the highest in vitamin D content. Maitake mushrooms can be especially potent, yielding up to 562 IU per 50 grams after treatment.

Mushrooms contain vitamin D2, while animal sources typically contain D3. While D3 may be slightly more effective at raising blood levels long-term, mushroom-derived D2 can still effectively increase vitamin D status, especially in those who are deficient.

While fortified foods like plant milks and cereals contribute to vitamin D intake, they may not be enough to meet daily requirements on their own. Combining fortified foods with UV-exposed mushrooms or supplements is often necessary.

For best results, slice your mushrooms and place them gill-side up in direct sunlight between 10 a.m. and 4 p.m. for 15 minutes to 2 hours. This process converts the ergosterol into vitamin D2.

Yes, lichen-derived vitamin D3 is safe and widely used in vegan supplements. It's an effective, plant-based source of cholecalciferol, which is otherwise derived from animal products like sheep's wool or fish oil.

Cooking does not completely destroy the vitamin D in mushrooms. Some studies show that vitamin D2 levels are stable even after frying, with minimal loss compared to boiling. Pan-frying is an effective method for cooking and retaining the vitamin.

The main difference is their origin and molecular structure. D2 (ergocalciferol) comes from plants and fungi, while D3 (cholecalciferol) is produced in animals and, in the case of vegan sources, lichen. Some research suggests D3 is more effective for maintaining blood levels long-term.