December 23, 2013 | 1 minute read

Q:        Are mushrooms really a good source of vitamin D?

A:        Most mushrooms supply an insignificant trace of vitamin D. However, research shows that exposing mushrooms to ultraviolet light from the sun or a sunlamp for a few hours before harvest or five to 15 minutes after harvest can trigger production of vitamin D within the mushroom. Enriched mushrooms treated in this manner can contain close to 400 IU of vitamin D in three ounces of raw mushrooms (about four to five medium white button or brown crimini, or one portabella). That’s two-thirds of the 600 IU that is the current U.S. recommendation for people age one to seventy. If you see these mushrooms in the store, it’s one way to get your vitamin D. With or without the D, however, using a substantial portion in mixed dishes like casseroles and chili allows you to maintain a hearty texture with smaller amounts of meat. Meanwhile you are getting a variety of natural compounds under study for potential benefits to immune function and health.