In the same study, the astragalus root was found to increase the life span of human cells in culture. The authors report no toxicity to human cells. The treated cells also became resistant to a common virus and astragalus promoted regeneration of cells in the bronchi of virus-infected mice. As if this weren't impressive enough, another study probed the activity of macrophages, one of the major cells responsible for consuming invading microbes. The activity of the macrophages was significantly enhanced within six hours of treatment, and the enhancement persisted for at least seventy-two hours.
Most consumers probably use astragalus to prevent and treat colds and other minor diseases.
In the Chinese research mentioned above, astragalus reduced the incidence of common colds among users, and shortened the duration of colds by almost half. It's also one of America's most popular herbal products, also used to prevent and treat the common cold, influenza and infections. Echinacea is the best known and one of the most researched of immunostimulants. Echinacea was among the most popular herbs used by Native American Indians. At least 14 tribes used Echinacea for a coughs, colds, sore throats, infections, toothaches, inflammations, tonsillitis, and snake bites, among other uses.