Any way you slice it, the oyster mushroom is truly impressive. Oyster mushrooms come in several varieties and colors and are some of the most nutritious types of mushrooms you can find. Already known and sought after for their delicate and flavorful taste, oyster mushrooms are attracting a large following due to their nutritional and medicinal qualities. In addition to being a high source of protein and vitamins, research has shown oyster mushrooms to help lower cholesterol, help prevent plaque buildup in arteries, boost the immune system, help lubricate joints, and reduce inflammation. Use of the oyster mushroom even in cancer treatment shows promise according to ongoing research.