Immune Renew is a healthy immune supporting formulation containing Standardized Astragalus Extract and a High Beta-Glucan Propriety Mushroom Blend. Astragalus has been shown to support number pf aspects of healthy immune function, including the enhancement of T-Cell and Natural Killer Cell activity. Natural killer cells are named because they destroy unhealthy cells in the body virtually on contact. Mellen brand of Immune Renew contains blend of eight organic mushrooms which provide additional support due to its high 1, 3 form of Beta Glucan content. 1, 3 Beta Glucans are especially valuable to healthy immune function.