Expert reveals the cooking hack that makes mushrooms '20 times more nutritious'

Mushrooms are already celebrated as one of nature's most versatile superfoods, but experts say a simple kitchen hack could supercharge their benefits, making them up to 20 times richer in vitamin D.

Elliot Webb, founder of Urban Farm-It and author of Growing Mushrooms at Home, has explained how exposing mushrooms to sunlight before cooking transforms them into a nutritional powerhouse.

"Most people know that our own skin produces vitamin D when exposed to sunlight," Webb said.

"But mushrooms work in a similar way. They contain a compound called ergosterol, which converts into vitamin D2 when exposed to ultraviolet light. That means simply leaving your mushrooms in direct sunlight can dramatically boost their vitamin D levels."

Ordinarily, a portion of mushrooms contains only one or two micrograms of vitamin D. According to Webb, the sunlight method can increase this amount by as much as twenty-fold.

"Just 15 to 30 minutes of sun exposure to your mushrooms can make a real difference," he explained. "You don't need any specialist equipment, it's a natural, cost-free way to make your meals more nutritious."

With many people in the UK struggling to get enough vitamin D, especially in the darker months, supplements have become a common solution. But Webb believes sun-exposed mushrooms could offer a simple, affordable alternative.

"Sun-exposed mushrooms are an excellent source of vitamin D, especially for those following plant-based diets," he said. "This method has been widely recognised in Scandinavian countries, where wild mushrooms naturally exposed to sunlight have long been valued for their nutritional benefits."

The hack isn't just hearsay. Webb points to scientific studies showing how effective UV exposure can be. "Research has demonstrated that even dried mushrooms exposed to UV light can generate nutritionally significant amounts of vitamin D," he said.

"In commercial mushroom farming, UV lamps have been used to enhance mushrooms in just seconds. It's a proven method."

While the sunshine trick is catching attention, Webb emphasises that mushrooms already have plenty to offer. "They are a great source of antioxidants, fibre, and essential minerals," he said. "Incorporating them into your diet regularly can support overall well-being."

Whether scattered on a pizza, tossed into a stir-fry, or roasted as a side dish, leaving mushrooms to bathe in sunlight before they hit the pan could be one of the easiest, and cheapest, ways to make your diet healthier.