Astragalus is an herb native to northern China.
While more than 2,000 varieties of astragalus exist worldwide, the Chinese version is the type that has been tested most extensively. Astragalus contains numerous compounds, including flavonoids, polysaccharides, amino acids and trace minerals. Traditionally, it was used in China for conditions such as night sweats, diarrhea, and qi deficiency. Preliminary studies conducted in Asia have determined that astragalus can enhance immune function and lengthen the lives of people with cancer. Other studies suggest that it may prevent some infections in people undergoing dialysis for kidney failure.