Astragalus has been integral to Chinese traditional medicine for over 2000 years. Dried Astragalus root is often added to soup for flavor and health purposes. Astragalus root contains therapeutic substances that help stimulate the immune system. It is a tonic to increase stamina, strengthen disease resistance, and improve general health. Some studies show that Astragalus may even act as an antibiotic and antiviral agent, and it may even counteract some of the negative effects of stress.