Abstract 001: Quantity and Variety in Fruit and Vegetable Intake and Risk of Coronary Heart Disease
Epidemiological data have consistently documented a protective effect of fruit and vegetable intake on risk of coronary heart disease (CHD). Consequently, dietary guidelines recommend increasing fruit and vegetable intake and, most recently, have also suggested increasing variety. Our objective was to examine the independent roles of quantity and variety in fruit and vegetable intake in relation to incident CHD. We prospectively observed 71,157 women from the Nurses’ Health Study (NHS, 1984-2008) and 39,752 men from the Health Professionals Follow-up Study (HPFS, 1986-2008) who were free of diabetes, cardiovascular diseases, and cancer at baseline. We documented 2585 incident CHD cases in women during 24 years of follow-up and 3408 cases in men during 22 years of follow-up. Diet was assessed using a standardized and validated questionnaire and updated every 4 years. Variety was defined as the number of unique fruits and vegetables consumed at least once per week. To account for minor differences in the number of fruit and vegetable items administered at each follow-up cycle, we standardized our variety score to 30 (11 for fruit score and 19 for vegetable score). Potatoes, soy, or other legumes were not included in our analyses. Because the AHA does not consider fruit juice to be equivalent to whole fruit, fruit juice was also not included in our analyses. Quantity (servings/day) and variety in fruit and vegetable intake were correlated (r=0.68, P<0.0001). We, therefore, regressed variety on quantity to assess their independent effects on CHD risk. In multivariable analyses, after adjusting for dietary and non-dietary covariates, those in the highest fifth of fruit and vegetable intake (median intake=7.80 servings/day) had a 13% lower risk (95% CI, 0.79 to 0.95) of CHD compared to those in the lowest fifth (median intake=2.14 servings/day). Conversely, quantity-adjusted variety was not associated with CHD risk (RR for highest fifth compared to lowest fifth=1.04, 95% CI, 0.92 to 1.19). Further, within each category of quantity, higher variety was not associated with CHD risk. Our data suggest that absolute quantity, rather than variety, in fruit and vegetable intake is associated with a significantly lower risk of CHD. Future work should examine the role of variety in reducing biological markers of inflammation and endothelial dysfunction. Meanwhile, policy efforts should continue to focus on increasing overall fruit and vegetable intake.
- © 2013 by American Heart Association, Inc.