Reishi (Ganoderma lucidum), has been highly praised for thousands of years for its effects on longevity. In ancient times, those seeking immortality often used reishi mushrooms because of this belief. Reishi contains powerful beta-glucans, one of the most effective and powerful immune system boosters that we know of. Reishi regulates the immune system and reduces the excess when the normal adaptive immune system responds excessively. It is also known to be a powerful Shen tonic, bringing peace to body, mind and spirit.