Mushrooms and Vitamin D: UV-Exposed Mushrooms and What Labels Say
Why most mushrooms hold little vitamin D, what ultraviolet exposure changes, what USDA values and human trials show, and how to read a label that mentions vitamin D.
Content last updated . This page has not been medically reviewed.
Safety first. Supplements can cause side effects and interact with medicines. Read mushroom safety and interactions before you use any mushroom product.
Mushrooms can carry vitamin D, but the amount depends on how the mushroom was grown and handled, and trials show that eating them does not always raise a person's vitamin D blood level. This page covers cultivated edible mushrooms eaten as food.
Why ultraviolet light matters
A trial team described mushrooms as containing very little vitamin D2 but plenty of ergosterol, a compound that ultraviolet (UV) light can convert into vitamin D2. [1] Vitamin D2 (ergocalciferol) is one form of vitamin D. The other common food and supplement form is D3. Our vitamin D2 vs D3 page explains the difference.What USDA FoodData Central lists
Per 100 grams raw, the standard white button entry lists 0.2 micrograms (mcg) of vitamin D (7 IU), while the entry for white mushrooms exposed to ultraviolet light lists 26.2 mcg (1,050 IU). [2] [3] The same pattern appears for exposed crimini (31.9 mcg) and portabella (28.4 mcg) entries. [3]| Raw entry, per 100 g | Vitamin D (mcg) | Vitamin D (IU) |
|---|---|---|
| White, standard | 0.2 | 7 |
| White, exposed to UV | 26.2 | 1,050 |
| Portabella, standard | 0.3 | 10 |
| Portabella, exposed to UV | 28.4 | 1,140 |
| Crimini, standard | 0.1 | 3 |
| Crimini, exposed to UV | 31.9 | 1,280 |
| Shiitake, standard | 0.4 | 18 |
| Oyster, standard | 0.7 | 29 |
| Enoki, standard | 0.1 | 5 |
| Maitake, standard | 28.1 | 1,120 |
| Morel, standard | 5.1 | 206 |
| Chanterelle, standard | 5.3 | 212 |
The values are as listed in the entries. [2] [3] The database entries we read do not explain why maitake, morel and chanterelle are higher than other untreated entries, so this page does not guess. The entries are one sample each.
What human trials found
Label: mixed. Vitamin D2 from UV-exposed mushrooms is absorbed, but its effect on total vitamin D status varies.| Study | Who and what | What it found |
|---|---|---|
| Systematic review and meta-analysis of 6 randomized trials (2016) | Healthy adults eating UV-exposed mushrooms | Total blood vitamin D was not significantly increased overall; it rose in the 3 European trials (lower starting levels) but not in the 3 US trials [4] |
| Randomized trial, 26 young adults with low levels, 5 weeks in winter (2011) | UV-B button mushrooms in a soup giving 28,000 IU (700 mcg) of D2 vs a D2 supplement vs placebo | Blood levels rose similarly in the mushroom and supplement groups [1] |
| Randomized trial, 38 healthy adults, 6 weeks (2012) | UV-treated white button mushrooms giving 8.8 or 17.1 mcg per day | D2 markers rose and D3 markers fell, so total vitamin D status did not change [5] |
| Randomized trial, 43 prediabetic adults with low levels and overweight, 16 weeks (2014) | 100 g cooked UVB mushrooms daily | Modest or no increase; the authors reported D2 loss on cooking [6] |
| Randomized trial, 41 adults with overweight or class I obesity, 6 weeks over winter (2026) | 84 g fresh UV mushrooms twice a day, produced to contain 400 IU D2 per serving | Total vitamin D still declined as the season changed; only 67 percent of the mushrooms contained D2 [7] |
The meta-analysis authors concluded UV-exposed mushrooms may raise vitamin D when baseline status is low, with a smaller drop in D3. [4] The amount in the first trial is a trial amount, far above a normal serving, and is not a suggestion for anyone. Funding was not described in the abstracts we read.
What a label may and may not tell you
- A nutrition label states vitamin D as a percent of the Daily Value (DV), and the FDA lists the vitamin D DV as 20 mcg. [8]
- FDA explains that 5 percent DV or less is low and 20 percent or more is high. [8]
- Ordinary mushrooms may show little or none, while UV-exposed ones can show a lot. By our arithmetic from the USDA entry, 100 g of the UV-exposed white entry is 26.2 mcg, well above the 20 mcg DV. [3]
- Amounts can differ between packages. In the 2026 trial, a third of the mushrooms produced to contain D2 did not. [7] The sources we read do not describe how often labels match contents.
- Powders, capsules and extracts sold for medicinal reasons are different products. Whether they contain vitamin D is not described in the sources we read, so check the supplement facts and see how to read a mushroom supplement label.
Frequently asked questions
Do all mushrooms contain vitamin D?
No. In USDA FoodData Central the standard white button entry lists 0.2 mcg per 100 g, while some other entries and UV-exposed entries list far more. [2] [3]
How does a mushroom make vitamin D?
Ultraviolet light converts ergosterol in the mushroom into vitamin D2, according to a randomized trial team. [1]
Can UV-exposed mushrooms fix low vitamin D?
Proper evidence not found that they reliably do. We searched PubMed for trials and meta-analyses; results were mixed. [4] Ask a clinician about testing.
Does cooking reduce the vitamin D?
The authors of one trial reported unexpected D2 loss from fresh UVB mushrooms on cooking. [6] We did not find a general cooking-loss figure.
Is mushroom vitamin D2 the same as D3?
They are different forms. In one trial, D2 raised D2 markers while D3 markers fell. [5]
More details: evidence, limits and cautions
The details behind this page: cautions, limits of the evidence and where sources disagree. Open any note to read it.
Safety and who should ask
References
- Urbain P, et al. Bioavailability of vitamin D2 from UV-B-irradiated button mushrooms in healthy adults deficient in serum 25-hydroxyvitamin D: a randomized controlled trial. Eur J Clin Nutr. 2011. Read 2026-10-22.
- U.S. Department of Agriculture, FoodData Central, SR Legacy entries for raw mushrooms: white 169251, crimini 168434, portabella 169255, shiitake 169242, oyster 168580, enoki 169382, maitake 169403, morel 168423, chanterelle 168422. Read 2026-10-22.
- U.S. Department of Agriculture, FoodData Central, SR Legacy entries for mushrooms exposed to ultraviolet light: white 169376, portabella 170143, crimini 168557. Read 2026-10-22.
- Cashman KD, et al. Effect of ultraviolet light-exposed mushrooms on vitamin D status: systematic review plus meta-analysis. J Nutr. 2016. Read 2026-10-22.
- Stephensen CB, et al. Ergocalciferol from mushrooms or supplements consumed with a standard meal increases 25-hydroxyergocalciferol but decreases 25-hydroxycholecalciferol in the serum of healthy adults. J Nutr. 2012. Read 2026-10-22.
- Mehrotra A, et al. Bioavailability of vitamin D2 from enriched mushrooms in prediabetic adults: a randomized controlled trial. Eur J Clin Nutr. 2014. Read 2026-10-22.
- Comboni LM, et al. Does consuming fresh ultraviolet light-exposed mushrooms offset the seasonal decline in serum total 25OHD in adults classified as overweight and class I obese? A randomized controlled trial. Foods. 2026. Read 2026-10-22.
- U.S. Food and Drug Administration. Daily Value on the Nutrition and Supplement Facts Labels. Read 2026-10-22.