Vitamin D is an essential nutrient that helps the body form and maintain healthy bones and teeth. More recent research has shown that it helps regulate the immune system, lowering the risk of infection, cancer, heart disease and autoimmune diseases.
Yet as fear of skin cancer has grown and populations have become more sedentary, exposure to sunlight has dropped dramatically and vitamin D deficiency has surged.
“There’s a better understanding of importance of vitamin D in human health,” said Tara McHugh, a mushroom researcher at the U.S. Department of Agriculture.
The skin cannot synthesize vitamin D if covered in sunscreen. But dietary sources, such as fortified milk or fatty fish, cannot really provide enough of the nutrient for optimal health.
Three ounces of mushrooms exposed to a short burst of ultraviolet radiation, in contrast, contain a fully daily dose of the vitamin, more than three times the amount found in a cup of fortified milk. The radiation does not affect the mushrooms’ other nutritional qualities, taste, appearance or shelf life.