Q: Is it true that you should never eat mushrooms raw?
–Lisa Enslow, 48, Chatham, NJ
A: Yes. Mushrooms have very tough cell walls and are essentially indigestible if you don't cook them. Thoroughly heating them releases the nutrients they contain, including protein, B vitamins, and minerals, as well as a wide range of novel compounds not found in other foods. In Asian traditions, mushrooms are regarded as both food and medicine because they can support the body's natural defenses by enhancing the immune system.
But there are other reasons to cook your mushrooms. Raw mushrooms contain small amounts of toxins, including some compounds that are considered carcinogens. These are destroyed by cooking them thoroughly. Broiling or grilling is best.
Because of these concerns and because they offer little in the way of improving health, common button mushrooms are best avoided. But the types eaten in Asia—shiitake, maitake, oyster mushrooms, and enoki—provide a range of health benefits. The shiitake may be my favorite: It appears to enhance immunity and reduce the risk of several types of cancer. Maitake contains complex sugars called beta-glucans that have immune-enhancing effects. Oyster mushrooms contain compounds that can help address high cholesterol. Other mushrooms are used strictly in traditional medicinal preparations. Cordyceps mushrooms are used to increase aerobic capacity and support lung function. Reishi helps fight cancer. Lion's Mane contains a nerve-growth compound that has potential for treating nerve disorders.