American Cancer Society Guidelines on Diet and Cancer Prevention

American Cancer Society
Thursday, 9 October 1997

Atlanta 1997/10/09 -The key recommendation of a recently released global report on diet and cancer prevention -- that individuals should choose a predominantly plant-based diet that includes a variety of vegetables, fruits, and grains -- is consistent with the American Cancer Society's guidelines on diet, nutrition and cancer prevention, and adds to the evidence supporting a link between diet and cancer. The report, entitled Food, Nutrition and the Prevention of Cancer: A Global Perspective, concludes that 30 to 40 percent of cancers are directly linked to dietary choices, and reaffirms the Society's recommendations for helping people reduce their risk of cancer.

The report was underwritten by the American Institute for Cancer Research (AICR) and the World Cancer Research Fund, and was released October 1 in London. The report will be presented during the AICR Research Conference October 8-10 in Washington, DC.

The new report is the most comprehensive review of scientific evidence on diet, nutrition and cancers to date and the first to examine the role of food in cancer prevention from an international perspective. Begun in 1993, the study was conducted by 15 of the world's leading diet and cancer researchers.

In addition to emphasizing increased consumption of vegetables, fruits, legumes, and grain-based foods, which have been shown to have a protective effect particularly for cancers of the gastrointestinal and respiratory tracts, the report highlights the importance of staying physically active and maintaining a healthy body weight. The American Cancer Society concurs with these recommendations with only minor exceptions. In the area of physical activity the Society recommends at least 30 minutes of moderate physical activity on most days of the week, while the global report calls for one hour of physical activity every day. Studies have shown that physical activity can help protect against some cancers, either by balancing caloric intake with energy expenditure or by other mechanisms. An imbalance of caloric intake and output can lead to overweight, obesity, and increased risk for cancers at several sites, including colorectal, prostate, endometrium, breast (among postmenopausal women) and kidney.

Another difference in the AICR report and the Society's guidelines involves consumption of red meat and alcohol. The report states that if red meat is eaten at all, intake should be limited to less than three ounces daily. The Society recommends limiting consumption of meats, especially high-fat meats, but does not suggest specific portion amounts. Foods from animal sources remain major contributors of total fat, saturated fat, and cholesterol in the American diet. Although meats are good sources of high-quality protein and supply many important vitamins and minerals, consumption of meat--especially red meats--has been linked to cancers at several sites, most notably colon and prostate.

Similarly, the report recommends that individuals do not drink alcohol, but, if they do, to limit alcoholic drinks to less than two drinks a day for men and one for women. The Society recommends limiting consumption of alcohol, if people drink at all, but again, does not make a specific recommendation regarding alcohol intake. Alcoholic beverages, along with cigarette smoking, cause cancers of the oral cavity, esophagus, and larynx. Cancer risk increases with the amount of alcohol consumed and may start to rise with intake of as few as two drinks per day. Moderate alcohol intake has been shown to decrease the risk of coronary heart disease, at least in middle-aged adults, and these cardiovascular benefits may outweigh the risk of cancer in men older than 50 and in women older than 60.

"The AICR recommendations are virtually identical to those made by the American Cancer Society, aside from the several small exceptions described above," says Clark W. Heath, Jr., MD, vice president of Epidemiology and Surveillance Research for the American Cancer Society. "The AICR recommendations have a broad global orientation, of course, in contrast to the Society's national perspective. Hence, they give somewhat greater emphasis to matters of food preservation and preparation, while directly questioning the value of dietary supplements when diet practices are adequate," says Dr. Heath.

The American Cancer Society's nutrition guidelines were last reviewed in 1996 (the Society's nutrition guidelines were first published in 1984 and later reviewed in 1991). The Society has long concluded that dietary practices and physical activity--along with smoking cessation, avoidance of occupational carcinogens, and early detection--are important factors in the prevention of cancer and cancer death.

Although no diet can guarantee full protection against disease, the Society believes that the following recommendations, which are in line with guidelines of other health agencies, offer the best nutrition information currently available to help Americans reduce their risk of cancer:

1. Choose most of the foods you eat from plant sources

Eat five or more servings of fruits and vegetables each day

Eat other foods from plant sources, such as breads, cereals, grain products, rice, pasta, or beans several times each day

2. Limit your intake of high-fat foods, particularly from animal sources

Choose foods low in fat

Limit consumption of meats, especially high-fat meats

3. Be physically active: Achieve and maintain a healthy weight

Be at least moderately active for 30 minutes or more on most days of the week

Stay within your healthy weight range

4. Limit consumption of alcoholic beverages, if you drink at all

The American Cancer Society is the nationwide, community-based, voluntary health organization dedicated to eliminating cancer as a major health problem by preventing cancer, saving lives and diminishing suffering from cancer, through research, education, advocacy, and service. For more information about cancer or the American Cancer Society and its programs, contact your local American Cancer Society or call 1-800-ACS-2345.

For a copy of the American Cancer Society's nutrition guidelines, which include diet and activity factors that affect risks for the most common cancers, along with common questions about diet and cancer, please call 404-329-5735. For a copy of Food, Nutrition and the Prevention of Cancer: A Global Perspective, contact Sara Purcell, 202-328-7744, or Lynn Forsyth, 202-828-8808.

For more information, or to contact American Cancer Society, see their website at: www.cancer.org