Chaparral contains an ingredient called nor-dihihydroguairetic (NDGA), a potent antitumor agent. NDGA inhibits aerobic and anaerobic glycolysis (the energy-producing ability) of cancer cells. The flavonoids present in chaparral have strong antiviral and antifungal properties. Chaparral is not recommended for use in people with poor kidney function. The chaparrals are a group of closely related wild shrubs found in the desert regions of southwestern United States and northern Mexico, as well as in the dry regions of South America, such as Argentina and Bolivia. Chaparral products found in health food stores usually consists of leaflets and twigs. The branched bush grows up to 2 to 6 ft. with small, dark-green leaves that turn bright green after rain and have a resinous texture.