Host Defense�® has been shown to increase human Natural Killer (NK) Cell activity by up to 300%.* The immune-enhancing power of Host Defense comes from two sources: the unsurpassed quality of the MycoMedicinal™ mushrooms, and the proprietary combination of species. Each of the MycoMedicinal species has, on its own, an ability to support human immune functioning, but the combination of these 16 mushroom sources creates synergies, waves of reinforcement, that bathe us in immune support.* There is glory in each mushroom, but greater glory in the whole. For maximum benefit take with New Chapter�®'s Gingerforce�® Supercritical Therapy™ formulation to increase bioavailability and activity. Potency Assured™ for Arabinoxylanes, Glycoproteins, Ergosterols, and Beta Glucans.