Phytochemicals are compounds found in plants. The phytochemicals below are being investigated to see if they are beneficial to human health; even when extracted from the plant from which they originate. In recent years, there has been a large amount of research to investigate the usefulness of specific natural compounds in the prevention and treatment of cancer. The list below is not meant to be complete. There are numerous other chemicals that are being examined. We have chosen some of the best-studied and most widely publicized agents: