Which mushroom has vitamin D? Your guide to dietary sources

November 10, 2025 •

4 min read

According to research, while many commercially-grown mushrooms have very little vitamin D, fresh or dried mushrooms exposed to ultraviolet (UV) light can generate high levels. This reveals a fascinating truth about which mushroom has vitamin D and how to maximize its benefits.

Quick Summary

Mushrooms containing ergosterol produce vitamin D2 when exposed to sunlight or UV light. Varieties like shiitake and portobello can be significantly enhanced, offering a potent, non-animal source of this essential nutrient.

Key Points

UV Exposure is Key: Commercial mushrooms are grown in the dark and have negligible vitamin D unless they are deliberately exposed to UV light.
Shiitake and Portobello are Top Performers: These varieties, especially when UV-treated or sun-dried, are excellent sources of vitamin D2.
Sunlight is Effective at Home: You can increase vitamin D in your mushrooms by placing sliced, gill-side-up mushrooms in the sun for 15-30 minutes.
D2 is a Viable Source: The vitamin D2 produced by mushrooms is a bioavailable form that can effectively increase and maintain vitamin D status, particularly in deficient individuals.
Cooking Effects Vary: The retention of vitamin D depends on the cooking method; dry heat methods like grilling are better for preserving vitamin D than boiling.
Dried Mushrooms Store Vitamin D Well: Sun-drying mushrooms significantly increases their vitamin D content, which remains stable for many months in airtight containers.

The Science Behind Mushrooms and Vitamin D

Unlike plants or animals, mushrooms are fungi and contain a unique compound called ergosterol in their cell walls. This ergosterol is a precursor to vitamin D2 (ergocalciferol) and, much like how human skin synthesizes vitamin D3 from cholesterol when exposed to UV-B rays, mushrooms convert ergosterol into vitamin D2 under similar conditions.

The key takeaway is that the vitamin D content in a mushroom is not inherent or constant; it is directly related to its exposure to UV light. This is why wild mushrooms, which grow outdoors, often contain higher natural vitamin D levels than their cultivated, dark-grown counterparts. For commercially available mushrooms, this UV exposure is often a controlled, post-harvest process.

Different Types of Vitamin D

It is important to understand the different forms of vitamin D. Animal-based foods and human skin produce vitamin D3 (cholecalciferol). Mushrooms, on the other hand, primarily produce vitamin D2. While some earlier studies suggested D2 was less effective at raising overall vitamin D levels than D3, recent research indicates that D2 from mushrooms can be just as effective as supplemental D2 or D3 in raising and maintaining vitamin D status in deficient adults. This makes UV-exposed mushrooms a powerful food-based solution for addressing vitamin D deficiency globally, especially for vegans and vegetarians.

Which Mushroom Has Vitamin D? A Closer Look at Varieties

While most common edible mushrooms can be fortified with vitamin D through UV exposure, certain types stand out for their ability to generate and retain the nutrient. Wild mushrooms like chanterelles and morels, due to natural sun exposure, can contain very high levels of vitamin D2. However, for supermarket shoppers, focusing on UV-treated varieties is the most reliable strategy. Key varieties to consider include:

Shiitake Mushrooms: Known for their rich, umami flavor, dried shiitake are an excellent source of vitamin D, particularly when UV-treated or sun-dried. Some studies have shown that dried, irradiated shiitake mushrooms can contain exceptionally high levels of D2.
Portobello and Cremini (Baby Bellas): These are the same species as the common white button mushroom, but at a different growth stage. When exposed to UV light, they can produce significant vitamin D content. UV-treated portobellos, for instance, have been shown to contain over 400 IU of D2 per 100g serving.
Maitake Mushrooms: Also known as 'Hen of the Woods', maitake can also be a strong source, with some proprietary growing methods exposing them to UV light to boost their vitamin D content significantly.
Oyster Mushrooms: These delicate, fan-shaped mushrooms also respond well to UV-light exposure, producing high levels of vitamin D2.

How to Create Vitamin D-Rich Mushrooms at Home

It is surprisingly simple to increase the vitamin D content of your store-bought mushrooms. By mimicking the sun exposure that wild mushrooms receive, you can boost their nutritional value significantly. Here is a simple process:

Purchase: Buy fresh white button, portobello, or shiitake mushrooms from your local grocery store. Since most are grown in the dark, their starting vitamin D level will be minimal.
Slice for Surface Area: Slice the mushrooms to expose more of their surface area. This allows more ergosterol in the gills and caps to absorb UV light.
Position and Expose: Place the sliced mushrooms on a tray with the gill-side facing upwards. Place the tray in direct midday sunlight, ideally between 10 a.m. and 3 p.m..
Time it Right: Allow them to sit in the sun for at least 15 minutes, or up to an hour. Studies have shown that even 15 minutes is enough to generate a full day's recommended vitamin D intake. Longer exposure is safe and will produce even more vitamin D, but glass blocks UV rays, so ensure they are exposed directly.
Store or Cook: Use the mushrooms immediately or store them in an airtight container. Sun-dried mushrooms are shelf-stable for many months, and their vitamin D content remains high.

Comparison of Common Mushrooms for Vitamin D Potential


Mushroom Type	Typical Source	UV Exposure Needed?	Estimated Vitamin D Content*	Best for Vegans/Vegetarians?
Wild Chanterelle	Wild-foraged	Naturally Occurs	High (up to 1200 IU/3.5 oz)	Excellent, if safely sourced
UV-Treated Portobello	Supermarket	Yes (Commercial)	Very High (up to 400 IU/3.5 oz)	Excellent
DIY Sun-Exposed Button	Supermarket	Yes (Home Method)	High (up to 400 IU/3.5 oz)	Excellent
Dark-Grown Button	Supermarket	No	Low (less than 40 IU/3.5 oz)	Poor
Sun-Dried Shiitake	Specialty Store	Yes (Sun-dried)	Very High (concentrated)	Excellent
Dried Maitake	Specialty Store	Varies (often UV-treated)	High (can be very high with proprietary methods)	Excellent

*IU (International Units) are per 3.5 ounces (100g) serving.

Cooking and Bioavailability

The vitamin D2 created in mushrooms is fat-soluble, so cooking methods matter. Boiling mushrooms can lead to some vitamin D loss as it can leach into the water. However, dry heat methods like grilling or pan-frying without oil result in high vitamin D retention. The vitamin D from mushrooms has shown to be bioavailable, meaning the body can effectively absorb and utilize it. Including some fat with your mushroom dish, like a light drizzle of olive oil, can also aid in absorption.

Conclusion: A Natural Boost to Your Health

By understanding which mushroom has vitamin D and how to activate it, you can easily turn a culinary staple into a powerful dietary ally. The process of exposing mushrooms to UV light, whether through a commercial process or a simple DIY method at home, transforms them from a negligible source to a significant one. For those with limited sun exposure or following a vegan diet, this makes mushrooms an invaluable, natural, and sustainable way to boost vitamin D intake and support overall health. For more scientific details on this topic, consult the comprehensive review from the National Institutes of Health. A Review of Mushrooms as a Potential Source of Dietary Vitamin D

Frequently Asked Questions

No. All mushrooms contain ergosterol, the precursor to vitamin D2, but only produce significant vitamin D when exposed to ultraviolet (UV) light. Wild mushrooms naturally gain vitamin D from sun exposure, while most commercially-grown varieties are grown in darkness and contain very little unless they are specifically treated with UV light.

For home-grown vitamin D enhancement, placing sliced mushrooms gills-up in direct midday sunlight for 15 to 30 minutes can generate a significant amount of vitamin D2. The exact amount depends on factors like time of day, season, and latitude.

Research has shown that for individuals with a vitamin D deficiency, the vitamin D2 from mushrooms can be effective in raising serum vitamin D levels, similar to supplemental vitamin D3. For vegans and vegetarians, it is a crucial non-animal source.

Dried mushrooms, particularly those that have been sun-dried, often have a much higher concentration of vitamin D2 than fresh mushrooms that haven't been exposed to UV light. However, fresh mushrooms can also be enriched with UV exposure before cooking.

While some mushrooms, particularly wild or UV-treated ones, can be eaten raw, cooking most varieties is generally safer. Furthermore, mushrooms grown in the dark have negligible vitamin D anyway. To maximize the benefit, rely on UV-exposed or sun-dried mushrooms, and know that cooking doesn't significantly diminish their vitamin D content.

Cooking does cause some reduction in vitamin D content, with different methods having varied effects. Boiling, especially for long periods, can reduce levels more than dry heat methods like grilling or pan-frying without oil, which retain higher amounts.

Some commercial mushroom growers intentionally expose their mushrooms to UV light and label them as 'UV-treated' or 'rich in vitamin D.' These can be found in many large supermarkets and online retailers.

No, mushrooms commercially treated with UV light are considered safe for consumption. Similarly, a reasonable duration of sun exposure for mushrooms you plan to cook at home is also safe. Always ensure any foraged mushrooms are properly identified to avoid poisonous varieties.