Medicinal mushrooms have been a part of the Chinese Materia Medica for several thousand years. These mushrooms, including reishi, oyster, maitake, shitake, and many more, have a strong effect on increasing immune function. For instance, Ling Zhi, or the reishi mushroom, has been studied for its immune enhancing effect, and has been found to increase T cell function. Classically, it is said that Ling Zhi tonifies Lung qi, transforms phlegm, and stops cough and wheeze. Additionally, it has been found to have a carcinostatic effect, meaning that it stops the growth of cancer cells. Nutritionally, mushrooms provide fiber while being low in fat and contain several groups of vitamins, particularly thiamine, riboflavin, niacin, biotin, ascorbic acid and Vitamin D.
Eating raw mushrooms is not advised, since some are toxic uncooked, and most do not break down enough in our digestive systems to offer much benefit this way. Mushrooms should always be cooked when used as food. A stronger concentrated extract (either capsule or liquid) will give you the most benefit for immunity.
Fungi Perfecti is a locally based producer of medicinal mushrooms and is considered the best source of organic, high quality mushroom extracts by most experts, including Bastyr University and Dr. Andrew Weil. Fungi Perfecti has a number of extract combinations that address a number of immune issues. A popular, general immune tonic is their Stamets 7 formula.