title: Primary prevention of colorectal cancer.
abstract: Colorectal cancer has been strongly associated with a Western lifestyle. In the past several decades, much has been learned about the dietary, lifestyle, and medication risk factors for this malignancy. Although there is controversy about the role of specific nutritional factors, consideration of dietary pattern as a whole appears useful for formulating recommendations. For example, several studies have shown that high intake of red and processed meats, highly refined grains and starches, and sugars is related to increased risk of colorectal cancer. Replacing these factors with poultry, fish, and plant sources as the primary source of protein; unsaturated fats as the primary source of fat; and unrefined grains, legumes and fruits as the primary source of carbohydrates is likely to lower risk of colorectal cancer. Although a role for supplements, including vitamin D, folate, and vitamin B6, remains uncertain, calcium supplementation is likely to be at least modestly beneficial. With respect to lifestyle, compelling evidence indicates that avoidance of smoking and heavy alcohol use, prevention of weight gain, and maintenance of a reasonable level of physical activity are associated with markedly lower risks of colorectal cancer. Medications such as aspirin and nonsteroidal anti-inflammatory drugs and postmenopausal hormones for women are associated with substantial reductions in colorectal cancer risk, though their utility is affected by associated risks. Taken together, modifications in diet and lifestyle should substantially reduce the risk of colorectal cancer and could complement screening in reducing colorectal cancer incidence.
authors.affiliation: Gastrointestinal Unit, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA. achan@partners.org <achan@partners.org>
authors.forename: Andrew T
authors.initials: AT
authors.lastname: Chan
authors.forename: Edward L
authors.initials: EL
authors.lastname: Giovannucci
mesh_terms: D000328:Adult; D000368:Aged; D000428:Alcohol Drinking / Q000009:adverse effects; D000818:Animals; D000893:Anti-Inflammatory Agents / Q000627:therapeutic use; D016588:Anticarcinogenic Agents / Q000627:therapeutic use; D015179:Colorectal Neoplasms / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control*; D004032:Diet / Q000009:adverse effects*; D015914:Estrogen Replacement Therapy; D005260:Female; D006801:Humans; D008019:Life Style; D008297:Male; D008875:Middle Aged; D018673:Nutrition Policy; D011322:Primary Prevention; D018570:Risk Assessment; D012307:Risk Factors; D040242:Risk Reduction Behavior; D057185:Sedentary Behavior; D012907:Smoking / Q000009:adverse effects; D016896:Treatment Outcome
chemical_list: D000893:Anti-Inflammatory Agents; D016588:Anticarcinogenic Agents