1. U.S. Department of Health and Human Services, Public Health Service. Healthy People 2000: national health promotion and disease prevention objectives—full report. DHHS publication no. (PHS) 91-50212. Washington, DC: U.S. Government Printing Office, 1991.
2. U.S. Department of Agriculture. Dietary Guidelines for Americans. Washington, DC: USDA, 1995.
3. American Heart Association.The American Heart Association Diet — an eating plan for healthy Americans. Dallas, 1985.
4. American Cancer Society. Nutrition, common sense, and cancer. New York: American Cancer Society, 1985.
5. A clinical trial of antioxidant vitamins to prevent colorectal adenoma;Greenberg;N Engl J Med,1994