Almost no vegetables contain vitamin D. Unlike vitamins A, C, and K, which are abundant in leafy greens and colorful produce, vitamin D is essentially absent from the plant kingdom. The one major exception is mushrooms, which aren’t technically vegetables but are sold alongside them in every grocery store. If you’re looking for plant-based sources of vitamin D, mushrooms are your best and really only option.
Why Vegetables Don’t Contain Vitamin D
Vitamin D production requires a specific precursor compound and ultraviolet light. In animals and humans, sunlight hitting the skin converts a cholesterol-related molecule into vitamin D3. Plants don’t have this molecule. They use different types of sterols for their cell membranes, and those sterols don’t convert to vitamin D under normal growing conditions.
Mushrooms are the exception because they’re fungi, not plants. Fungi contain a compound called ergosterol in their cell walls, and when UV light hits ergosterol, it converts to vitamin D2. Button mushrooms have especially high concentrations of this precursor compound. This is the same basic process that happens in human skin, just with a different starting molecule and a different form of vitamin D as the result.
How Much Vitamin D Mushrooms Actually Provide
Here’s the catch: most store-bought mushrooms contain almost no vitamin D. Mushrooms grown indoors in the dark never get the UV exposure needed to trigger the conversion. USDA testing found that typical raw white button mushrooms contain as little as 1 to 46 IU per 100 grams, depending on the batch. Raw shiitake mushrooms tested similarly low, ranging from 2 to 31 IU per 100 grams. For context, the recommended daily intake for adults under 70 is 600 IU.
UV-exposed mushrooms are a completely different story. When portobello mushrooms were treated with UV light for just 15 to 20 seconds, their vitamin D2 content jumped from about 10 IU to 446 IU per 100 grams. That’s roughly 75% of the daily recommendation in a single serving. Many grocery stores now sell mushrooms labeled “high in vitamin D” or “UV-treated,” and these are the ones worth seeking out if vitamin D is your goal.
You can also boost the vitamin D content of regular mushrooms at home. Place them gill-side up in direct sunlight for 15 to 30 minutes before cooking. The ergosterol in the mushroom tissue will convert to vitamin D2 even after harvest, since the cells are still intact.
Vitamin D2 vs. D3: A Real Difference
Mushrooms produce vitamin D2, while animal sources and your own skin produce vitamin D3. These two forms are not equally effective. A study published in The Journal of Clinical Endocrinology & Metabolism found that vitamin D3 raised blood levels more than three times as effectively as the same dose of D2. Over 28 days, participants taking D3 achieved blood levels roughly 3.4 times higher than those taking D2.
This doesn’t mean mushroom-derived vitamin D is useless. It still contributes to your overall intake, and UV-treated mushrooms can meaningfully supplement your diet. But if you’re relying on mushrooms as your primary source, you’ll need to eat more than the numbers on the label might suggest to get the same benefit as an equivalent amount of D3 from fish, eggs, or supplements.
Cooking Doesn’t Destroy It
One piece of genuinely good news: vitamin D in mushrooms survives cooking remarkably well. Research on UV-irradiated button mushrooms found that frying for 5 minutes, baking at 200°C for 10 minutes, and boiling for 20 minutes all retained at least 95% of the vitamin D2 content. Frying and baking performed slightly better than boiling, but the differences were small. You don’t need to eat mushrooms raw to get the benefit.
Other Plant-Based Options
Since vegetables themselves don’t provide vitamin D, the food industry fills the gap through fortification. Plant-based milks made from soy, almond, or oats are commonly fortified with vitamin D2 at levels up to 84 IU per 100 grams, which works out to roughly 200 IU per cup. That’s comparable to the fortification level in cow’s milk. Orange juice, cereals, and plant-based yogurts are also frequently fortified. Check the nutrition label, because fortification is voluntary and varies by brand.
Researchers at the John Innes Centre in the UK have developed gene-edited tomatoes that accumulate a vitamin D3 precursor. When exposed to UV light, these tomatoes produce about 20% of the daily recommended vitamin D per fruit, comparable to two medium eggs. These aren’t available to consumers yet, but they represent a potential future where you could get meaningful vitamin D from a vegetable garden.
Putting It Together
If your search brought you here hoping for a list of vitamin D-rich vegetables, the honest answer is that the list is very short. UV-treated mushrooms are the only produce-aisle item that delivers a significant amount. A 100-gram serving of UV-exposed portobellos gives you about 446 IU, which covers most of your daily need. Regular mushrooms from dark indoor farms provide almost nothing unless you give them some sun exposure yourself.
For adults up to age 70, the recommended daily intake is 600 IU. After 70, it increases to 800 IU. Between UV-treated mushrooms, fortified plant milks, and sunlight on your skin, it’s possible to meet that target on a plant-based diet. But vitamin D is one nutrient where the vegetable aisle genuinely can’t do the heavy lifting on its own.