A mushroom or toadstool is the fleshy, spore-bearing fruiting body of a fungus, typically produced above ground, on soil, or on its food source. Mushrooms are a rich, low-calorie source of fiber, protein, and antioxidants. They may also mitigate the risk of developing serious health conditions, such as Alzheimer's, heart disease, cancer, and diabetes. They're also great sources of Selenium. Use raw in salads, sautéed, breaded, or as an ingredient to enrich sauces, soups, or entrées.