The major constituent in ligustrum is ligustrin (oleanolic acid). Preliminary studies, mostly conducted in China, suggest that ligustrum stimulates the immune system, decreases inflammation, and protects the liver.¹ Ligustrum is often combined with astragalus in Traditional Chinese Medicine. Although used for long-term support of the immune system in people with depressed immune function or cancer, more research is needed to demonstrate the optimal length of time to use ligustrum.