New dietary anticarcinogens and prevention of gastrointestinal cancer.

Dietary anticarcinogens are found in minute amounts in many fruits and vegetables and often are the flavor and fragrance components that characterize them. Natural product chemists have isolated more than 100 chemical species from the plant kingdom that are antimutagenic, anticarcinogenic, or antipromotional in their mechanisms of inhibition. This paper will review the activity of newer agents including dialkyl sulfides in garlic and onion and calcium salts as potential compounds for the prevention of gastrointestinal cancer.