Do mushrooms contain vitamin D? Can mushrooms increase your vitamin D levels?

Every winter, I see a number of nutritionists recommend eating mushrooms to support vitamin D levels. However, this doesn’t necessarily make sense and the answer to the questions above is a bit more nuanced, so I wanted to weigh in on the discussion.

So do mushrooms contain vitamin D and can they increase your vitamin D levels? The answer is yes but also no. Let me explain…

Mushrooms CAN contain vitamin D but they don’t make a great source for two reasons:

1. Yes, mushrooms can contain a solid amount of vitamin D, but only when exposed to UV-B light. Without UV-B light, the vitamin D amount is negligible. You’ll either have to find mushrooms that have been exposed to plenty of sunlight or grown under UV-B lamps, or put your store bought mushrooms in the sun (or under a UV-B lamp) and they’ll convert that sunlight into vitamin D, just like humans do - pretty cool, no?!

   Note: contrary to popular belief though, this little hack does NOT work if you put them in your window sill since windows block out most of the UV-B rays.

2. Mushrooms can only generate vitamin D2, which is a far less superior form of vitamin D than vitamin D3. D2 (mostly found in mushrooms and supplements) is less effective at raising vitamin D levels than D3 (mostly found in animal products and supplements). This doesn’t mean D2 doesn’t work - it just means you have to consume far more of it to get the same effect you would from consuming D3.

Sources:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6213178/#:~:text=Whole%20oyster%20mushrooms%20have%20been,46%2C51%2C52%5D.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6213178/#:~:text=Vitamin%20D%2Denhanced%20mushrooms%20are,D%20for%20vegans%20and%20vegetarians.