Dietary patterns vary widely in such features as the consumption of fruits and vegetables, whole grains, red meat, fats, and dietary supplements, and these variations can have a major effect on the development of chronic diseases. The Health Professional’s Follow-Up Study and the Nurses’ Health Study were two long-term epidemiologic examinations of the relationships between recommended dietary behaviors and chronic disease risk in large populations. In an analysis of these studies published in the American Journal of Clinical Nutrition, McCullough et al. found that men and women whose diets most closely matched healthy dietary guidelines had a significant reduction in risk for all chronic diseases. For example, subjects who ate the healthiest diets cut their risk of cardiovascular disease (CVD) by as much as 48%.
The authors analyzed data from 38,615 men, aged 40 to 75 years, who participated in the Health Professional’s Follow-up Study between 1986 and 1990, and from 67,271 women, aged 30 to 55 years, who participated in the Nurses’ Health Study between 1984 and 1990.2 The authors designed an updated Alternative Healthy Eating Index (AHEI) to target food choices and macronutrient sources that are associated with reduced chronic disease risk, especially CVD risk. The AHEI provides quantitative scoring for adherence to dietary guidelines such as choosing more fish, poultry, and whole grains; increasing fruit and vegetable consumption; taking a daily multivitamin; and drinking alcohol only in moderation. The subjects were divided into quintiles according to the component AHEI score they received, based on how well these recommendations were followed in their diets.
Men in the highest-scoring quintile of the AHEI had 20% less of a risk of developing a major chronic disease. The association of AHEI score with health was somewhat weaker in women, for whom overall disease risk fell by 11%. The AHEI score was more strongly related to development of CVD than it was to cancer or other chronic diseases. After adjustment for age, both men and women in the highest quintile of AHEI compliance were 48% less likely to have an episode of CVD than those in the lowest quintile of compliance. The authors suggest that future research should focus on identifying more links between dietary patterns and cancer, as well as on examining chronic disease risk in the general population.
McCullough, Marjorie L, et al. Diet quality and major chronic disease risk in men and women: moving toward improved dietary guidance. Am J Clin Nutr 2002; 76:1261-71.