The American Cancer Society has developed guidelines for nutrition and cancer prevention. These guidelines are similar to the Dietary Guidelines for Americans and include the following:
* Choose most of the foods you eat from plant sources. * Limit your intake of high-fat foods, particularly from animal sources. * Be physically active. Achieve and maintain a healthy weight. * Limit consumption of alcoholic beverages if you drink at all.
The guideline stating to “choose most of the foods you eat from plant sources” has been recognized for years as important for good health. The Food Guide Pyramid illustrates this recommendation. More importantly, recent research has begun describing properties, specifically chemicals, contained in fruits, vegetables, grains, legumes, seeds, licorice root, soy, and green tea. Chemical compounds found in these foods are being recognized for their potential for protection against heart diasease and cancer.
As early as 1980, the National Cancer Institute Chemoprevention Program of the Division of Cancer Prevention and Control began evaluating phytochemicals for safety, efficacy, and applicability for preventing and treating diseases. Researchers have long known that there are phytochemicals present for protection in plants, but it has only been recently that they are being recommended for protection against human disease.
Although phytochemicals are not yet classified as nutrients, substances necessary for sustaining life, they have been identified as containing properties for aiding in disease prevention. Phytochemicals are associated with the prevention and/or treatment of at least four of the leading causes of death in the United States – cancer, diabetes, cardiovascular disease, and hypertension. They are involved in many processes including ones that help prevent cell damage, prevent cancer cell replication, and decrease cholesterol levels.