Shiitake contains all eight essential amino acids and a combination of vitamins and minerals, including vitamins A, B, B12, C, D and niacin. It is a source of polysaccarides for the maintenance of good health. Helps speed up the processing of cholesterol in the liver and helps to maintain healthy blood-sugar levels. Shiitake appears to activate the immune system’s cell-defense mechanism, including macrophages, natural killer cells and T-cells. It also helps to prevent immune system depression.