The relationship between food and cancer risk is getting attention as more and more studies point to the power of nutrients in fruits and vegetables to prevent disease. "There is increasing recognition that substances in the diet have real potential to prevent cancer. There is more and more information to support this view," said Richard Rivlin, MD, program director of the clinical nutrition research unit at Memorial Sloan-Kettering Cancer Center in New York City.

The concept of fighting cancer with nutrition is not new, but the body of evidence to support the claims continues to grow. There are now more than 200 studies which show the disease-fighting ability of phytochemicals such as beta-carotene, lycopene, and isoflavones, which are found in fruits, vegetables, and grains. Those are just a few of the phytochemicals that have been identified. There are hundreds of others that have not been identified yet. Scientists also don't know if individual phytochemicals, or a combination of them, result in reduced risk of cancer.

Research has shown the risk of prostate cancer drops for men who eat tomato products, possibly because of lycopene. In addition, it has been shown that colon cancer declines among those who drink green tea and regularly eat soy products and foods rich in selenium. Researchers don?t know exactly how phytochemicals work, but believe their potential in fighting cancer is enormous.

"There will be improved nutritional approaches," said Dr. Rivlin, adding that possibilities include genetically altered foods such as garlic with larger amounts of selenium. Dr. Rivlin also believes people with a family history or genetic predisposition to cancer will eventually be able to take supplements that are tailor-made to fight the disease.

Studies on nutrients and cancer prevention continue to add credence to the American Cancer Society's (ACS) dietary guidelines, according to Colleen Doyle, MS, RD, nutrition and physical activity director for the ACS.

Following are highlights from the ACS's guidelines on diet, nutrition, and cancer prevention:

• Choose most of the foods you eat from plant sources. "Evidence continues to mount that eating at least five servings of fruits and vegetables a day reduces the risk of cancer, especially colon and lung cancer," Doyle said.
• Limit your intake of high-fat foods, particularly from animal sources. High-fat diets have been associated with an increased risk of cancers of the colon, rectum, prostate, and endometrium.
• Be physically active: achieve and maintain a healthy weight. "Research confirms that small spurts of activity can add up to real health benefits," Doyle said. "Accumulating 30 or more minutes [a day] can make you feel better, help control your weight, reduce your risk of colon cancer, and improve your overall health."
• Limit consumption of alcoholic beverages, if you drink at all.  Alcohol consumption increases the risk of cancer of the mouth, esophagus, pharynx, larynx, and liver in men and women, and breast cancer in women, according to the guidelines.