Healthy Eating Index and C-reactive protein concentration: findings from the National Health and Nutrition Examination Survey III, 1988-1994

Objective: To examine whether diet quality is associated with C-reactive protein concentration. Design: Cross-sectional study using data from the Third National Health and Nutrition Examination Survey (1988-1994). Setting: Representative sample of the US population. Subjects: A total of 13 811 men and women aged greater than or equal to20 y. Interventions: We examined the cross-sectional associations between the Healthy Eating Index (HEI), a measure of diet quality according to the Dietary Guidelines for Americans, and serum C-reactive protein concentration. Dietary information was assessed using a 24-h recall. Results: After adjustment for age, sex, race or ethnicity, education, smoking status, cotinine concentration, body mass index, waist-hip-ratio, aspirin use, alcohol use, physical activity level, and energy intake, HEI score was inversely associated with an elevated C-reactive protein concentration in logistic regression analysis (odds ratio per 10 unit change: 0.92; 95th confidence interval (CI): 0.86-0.99). Among the components, only the score for grain consumption was inversely associated with an elevated C-reactive protein concentration. Compared with participants in the lowest quintile of number of servings of grain consumption, the adjusted odds ratios of having an elevated C-reactive protein concentration for participants in the second, third, fourth, and fifth quintiles were 0.87 (95th CI: 0.67, 1.12), 0.85 (95th CI: 0.69, 1.06), 0.79 (95th CI: 0.65, 0.96), and 0.68 (95th CI: 0.52, 0.88), respectively. Conclusions: Grain consumption may reduce inflammation. Our findings require confirmation.