TrueDEFENSE contains a combination of immune-enhancing herbs, such as astragalus, echinacea, ginseng, garlic and zinc to improve your natural defenses. Astragalus has been shown to boost resistance to infection and restore a weakened immune system. Echinacea has been shown to stimulate various mediators of the immune system. Ginseng has been shown to boost resistance to infection and to increase energy during times of stress. Garlic has been shown to protect against the cold and flu. Zinc has been shown to boost immunity and to improve tissue healing.