Supports Healthy Immune System Supports Healthy Natural Killer (NK) Cell Activity* A Dietary Supplement Vegetarian Formula NOW Mushroom GlycoNutrients is a nutritional supplement designed to support healthy immune function.; Mushroom GlycoNutrients contains RBAC, a glyconutrient compound called arabinoxylan that is formed when an extract of rice bran fiber is broken down with enzymes from the Shiitake mushroom.; Clinical studies have shown that RBAC has a number of beneficial effects on healthy immune function, including the ability to increase B-Cell and T-Cell counts, and to stimulate NK cell activity.In addition, RBAC helps to support overall healthy immune function. NOW Mushroom GlycoNutrients also contain a blend of Maitake, Reishi and Shiitake Mushrooms, which provides a high 1,3 Beta Glucan content.; Mushroom Beta Glucans have been shown to possess a remarkable ability to support both innate and adaptive healthy immune function.*