Experts Agree on Key Advice to Reduce Cancer Risk.

The connection between diet and cancer risk is astonishing. According to a recent report by the American Institute for Cancer Research and the World Cancer Fund, between three and four million cases of cancer worldwide could be prevented annually through dietary change.

The report, Food, Nutrition, and the Prevention of Cancer: A Global Perspective, presents a broad review of scientific evidence on diet, nutrition, and cancers. It offers some dietary recommendations that Americans have heard before from leading organizations such as the U.S. Department of Agriculture (USDA), the U.S. Department of Health and Human Services (DHHS), and the American Cancer Society (ACS) on reducing cancer risk. The report also contains some advice that is not in accordance with these other dietary guidelines.

Finding precise links between diet and cancer is not easy. For example, over 100 different cancers exist, each with its own set of causes. Furthermore, the number of components in the average diet is dizzying: Some components may decrease the risk, and others may increase it. With heart disease, there are risk factors like high blood cholesterol, but similar indicators may not exist to suggest cancer.

The study's key recommendation - to choose a predominantly plant-based diet that includes a variety of vegetables, fruits, and grains - echoes the 1996 ACS recommendation to choose mostly plant-based foods. Likewise, the USDA/DHHS Dietary Guidelines for Americans recommends a similar diet. The study noted that lean red meat can fit in a healthy diet. A recent survey showed that Americans consume about 2.6 ounces of red meat per day - well within the study's recommendation of 3 ounces per day.

The advice on plant-based foods stems from research showing compounds in plant foods that may help protect against potential cancer-causing agents. For instance, fiber, which is found only in plant foods, has a beneficial effect on the intestinal tract and may reduce the risk for some cancers.

Plant foods contain more than just fiber - they are also rich in phytochemicals that may be critical in controlling cell damage from free radicals and in regulating cellular proliferation.

Experts note, however, that Americans are not making such simple changes as eating the recommended five servings of fruits and vegetables every day, which could reduce cancer risk. Likewise, trends suggest a decline in physical activity among Americans.

The new report emphasizes the importance of physical activity and a healthy body weight. These recommendations are also in the USDA/DHHS and ACS guidelines. Physical activity not only helps reduce the risk of obesity, which may increase cancer risk, but also independently reduces the risk of certain cancers.

(Source: Food Insight, November/December 1997)