Phytochemicals are naturally occurring chemicals in plants that provide flavor, color, texture, and smell. Phytochemicals have potential health effects, as they may boost enzyme production or activity, which may, in turn, block carcinogens, suppress malignant cells, or interfere with processes that can cause heart disease and stroke. Phytochemical-rich foods include cruciferous vegetables (e.g., broccoli, Brussels sprouts, cauliflower, cabbage), umbelliferous vegetables (e.g., carrots, celery, parsley, parsnips), allium vegetables (e.g., garlic, onions, leek), berries, citrus fruits, whole grains, and legumes (e.g., soybeans, beans, lentils, peanuts). In the early twenty-first century, identification of the role of phytochemicals in health is an emerging area of science, and the global health community does not recommend supplementation with any specific phytochemicals.
M. Elizabeth Kunkel Barbara H. D. Luccia
Meskin, M. S.; Bidlack, A. J.; and Davies, A. J. (2002). Phtyochemicals in Nutrition and Health. Boca Raton, FL: CRC Press.