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Read in Creole...Scientific evidence suggests that about one-third of the cancer deaths that occur in the US each year is due to the adult diet, including its effect on obesity. Another third is due to cigarette smoking. Therefore, for the majority of Americans who do not use tobacco, dietary choices and physical activity become the most important modifiable determinants of cancer risk. The evidence also indicates that although inherited genes do influence cancer risk, heredity alone explains only a fraction of all cancer. Behavioral factors such as tobacco use, dietary choices, and physical activity modify the risk of cancer at all stages of its development. The introduction of healthful diet and exercise practices at any time from childhood to old age can promote health and probably reduce cancer risk.
Many dietary factors can affect cancer risk: types of foods, food preparation methods, portion sizes, food variety, and overall caloric balance. Cancer risk can be reduced by an overall dietary pattern that includes a high proportion of plant foods (fruits, vegetables, grains, and beans), limited amounts of meat, dairy, and other high-fat foods, and a balance of caloric intake and physical activity.
Based on its review of the scientific evidence, the American Cancer Society updated its nutrition guidelines in 1999. The Society’s recommendations are consistent in principle with the 1992 US Department of Agriculture (USDA) Food Guide Pyramid, the 1995 Dietary Guidelines for Americans, and dietary recommendations of other agencies for general health promotion and for the prevention of coronary heart disease, diabetes, and other diet-related chronic conditions. Although no diet can guarantee full protection against any disease, the Society believes that the following recommendations offer the best nutrition information currently available to help Americans reduce their risk of cancer.
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. Many scientific studies show that eating fruits and vegetables (especially green and dark yellow vegetables and those in the cabbage family, soy products, and legumes) protect against cancers at many sites, particularly for cancers of the gastrointestinal and respiratory tracts. Grains are an important source of many vitamins and minerals such as folate, calcium, and selenium, which have been associated with a lower risk of colon cancer in some studies. Beans (legumes) are especially rich in nutrients that may protect against cancer.
Choose foods low in fat; limit consumption of meats, especially high-fat meats. High-fat diets have been associated with an increase in the risk of cancers of the colon and rectum, prostate, and endometrium. The association between high-fat diets and the risk of breast cancer is much weaker. Whether these associations are caused by the total amount of fat, the particular type of fat (saturated, monounsaturated, or polysaturated), the calories contributed by fat, or some other factor in food fats, has not yet been determined. Consumption of meat, especially red meat, has been associated with increased cancer risk at several sites, most notably colon and prostate.
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 energy output can lead to being overweight or obese, and to increased risk for cancers at several sites: colon and rectum, prostate, endometrium, breast (among postmenopausal women), and kidney. Both physical activity and controlled caloric intake are necessary to achieve or to maintain a healthy body weight.
Alcoholic beverages, along with cigarette smoking and use of snuff and chewing tobacco, cause cancers of the oral cavity, esophagus, and larynx. The combined use of tobacco and alcohol leads to a greatly increased risk of oral and esophageal cancers; the effect of tobacco and alcohol combined is greater than the sum of their individual effects. Studies also have noted an association between alcohol consumption and an increased risk of breast cancer. The mechanism of this effect is not yet known, but the association may be due to carcinogenic actions of alcohol or its metabolites, to alcohol-induced changes in levels of hormones such as estrogens, or to some other process. Regardless of the mechanism, studies show that the risk of breast cancer increases with an intake beginning at just a few drinks per week. Reducing alcohol consumption is a good way for women who drink regularly to reduce their risk of breast cancer.
