People that ate 4oz of shiitake mushrooms for 4 weeks had improved immunity along with lower inflammatory markers.

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Could a mushroom a day help keep the doctor away? Some early evidence indicates that the Shiitake mushroom boosts immunity. Of the thousands of mushroom species globally, about 20 are used for culinary purposes. Shiitake mushrooms are native to Asia and are cultivated for their culinary and medicinal value.