Health Benefits of the SHIITAKE MUSHROOM Long a symbol of longevity in Asia because of their health-promoting properties, More recently, their rich, smoky flavor has endeared them to American taste buds. These exotic hearty mushrooms can now be found in supermarket shelves across the U.S. throughout the year. Like other mushrooms, these specialty mushrooms are as mysteriously unique as they are delicious. While often thought of as a vegetable and prepared like one, mushrooms are actually a fungus, a special type of living organism that has no roots, leaves, flowers or seeds.