For thousands of years, astragalus (Huang-Qi) has been used in China to restore life force. As an immune system booster, it strengthens general vitality, improves digestion and builds up the body's defense against viruses. Popularly found in tea and tablet form, we recommend selecting a product that contains an extract of the root, with 0.5% glucosides and 70% polysaccharides. For general well-being, this is a good tonic to keep in your routine, but alternate the use of astragalus with another immune-boosting herb such as echinacea, so as not to build up a tolerance to its healing effects.