Yes, vitamin D2 is vegan. It comes exclusively from fungi and yeast, not from any animal source. This makes it the most widely available form of vegan vitamin D, though you still need to check the label for non-vegan inactive ingredients like gelatin in the capsule itself.
Where Vitamin D2 Comes From
Vitamin D2 (ergocalciferol) starts as a compound called ergosterol, which is found naturally in fungi and yeast. Commercially, ergosterol is usually obtained from yeast that synthesizes it from simple sugars like glucose. To turn ergosterol into usable vitamin D2, manufacturers expose it to ultraviolet light, specifically UV-B rays, which trigger the conversion. This is the same basic process that happens when mushrooms sit in sunlight.
No animal products are involved at any stage. The raw material is fungal, and the conversion uses light energy rather than any animal-derived chemicals. This is fundamentally different from vitamin D3, which is typically sourced from lanolin (sheep’s wool oil) or fish liver oil.
The Label Still Matters
While vitamin D2 itself is always plant-sourced, the finished supplement on the shelf may not be fully vegan. Some D2 products use gelatin capsules or contain animal-derived fillers and binders. The NHS Specialist Pharmacy Service specifically flags this as a common issue when choosing vitamin D products for vegans. Look for supplements labeled “vegan” on the packaging, or check the inactive ingredients list for gelatin, lactose, or beeswax.
Tablet and liquid drop forms tend to be safer bets than soft gel capsules, which are more likely to contain gelatin. Some brands use plant-based capsule shells made from cellulose, so soft gels aren’t automatically off limits, but they do require closer inspection.
Vitamin D2 vs. D3 for Vegans
The practical question most vegans have is whether D2 works as well as D3. The honest answer: D3 raises overall blood levels of vitamin D more effectively. A meta-analysis of 20 comparative studies found that daily D2 supplementation raised total vitamin D blood levels about 40% less than the same dose of D3. So if you’re taking D2, you may need a higher dose to reach the same blood levels.
That said, D2 still raises your vitamin D levels meaningfully. It’s been used in clinical settings for decades and remains the form most commonly prescribed for vegans. The recommended daily intake for most adults is 15 mcg (600 IU), rising to 20 mcg (800 IU) for those over 70. If you’re relying on D2 specifically, some practitioners suggest aiming toward the higher end of supplementation ranges to compensate for the absorption difference.
Body weight also plays a role. The difference between D2 and D3 in raising blood levels was most pronounced in people with a BMI under 25. In people with a BMI above 25, the gap between the two forms largely disappeared.
Vegan D3 Now Exists
If the efficacy gap concerns you, there is now a vegan form of vitamin D3 made from lichen, a symbiotic organism of algae and fungi that grows on rocks and trees. Lichen-derived D3 gives you the more bioavailable form without any animal involvement. It’s become increasingly common in supplement stores over the past several years, though it typically costs more than standard D2 supplements.
For vegans who want the simplest, most affordable option, D2 works. For those who want the form that raises blood levels most efficiently, lichen-based D3 is worth the extra cost. Either way, you’re getting a fully plant-sourced nutrient, as long as you verify the capsule and fillers.
Food Sources of Vitamin D2
Beyond supplements, you can get vitamin D2 from UV-exposed mushrooms. Wild mushrooms naturally contain some D2, but cultivated mushrooms grown indoors are typically low in it unless they’ve been deliberately treated with UV light after harvest. Some brands now sell UV-treated mushrooms with significantly boosted D2 content, and the packaging will usually say so. Shiitake, maitake, and portobello mushrooms respond particularly well to UV exposure.
Fortified foods are another source. Many plant milks, orange juices, and cereals are fortified with vitamin D2 specifically because it’s plant-derived. Check the nutrition label: if it says “ergocalciferol,” that’s D2. If it says “cholecalciferol,” that’s D3, which may or may not be vegan depending on its source.