Effects of selected dietary constituents on high-sensitivity C-reactive protein levels in US adults

Background and aim: Growing evidence suggests that some of the effects of diet on cardiovascular disease (CVD) occur through mechanisms involving subclinical inflammation. We assessed the relationship between selected dietary constituents and serum high-sensitivity C-reactive protein (hsCRP) concentration in a population-based sample of United States adults. Methods: In this cross-sectional analysis, participants were selected from the US National Health and Nutrition Examination Survey (NHANES) and restricted to those with available data on dietary intake, biochemical and anthropometric measurements from 2001 to 2010. All statistical analyses accounted for the survey design and sample weights by using SPSS Complex Samples v22.0 (IBM Corp, Armonk, NY). Results: Of the 17,689 participants analysed, 8607 (48.3%) were men. The mean age was 45.8 years in the overall sample, 44.9 in men and 46.5 in women (p=.047). The age-, race-, sex-, energy intake- and body mass index-adjusted mean dietary intakes of total dietary fibre, polyunsaturated fatty-acids, vitamin E, vitamin A, vitamin B6, total folate, vitamin B family, vitamin C, vitamin K, magnesium, iron, copper and potassium monotonically decreased across increasing hsCRP quarters (p<.001 for all), whereas sugar intake increased (p<.001). In analysis of covariance adjusted for potential confounders (age-, race-, sex-, energy intake- and body weight-) hsCRP levels increased across increasing quarters of sugar intake (p<.001). Conclusions: This study provides further evidence of an association between dietary sugar, polyunsaturated fatty-acids, fibre and antioxidant intake and hsCRP levels, a subclinical inflammation marker. hsCRP concentrations are likely modulated by dietary intake.