Association between dietary glycemic index, glycemic load, and high-sensitivity C-reactive protein

Objective This study examined the relation between quality of dietary carbohydrate intake, as measured by glycemic index (GI) and glycemic load (GL), and serum high-sensitivity C-reactive protein (hs-CRP) levels. Methods During a 1-y observational study, data were collected at baseline and at each quarter thereafter. GI and GL were calculated from multiple 24-h dietary recalls (24HRs), 3 randomly selected 24HRs at every quarter, with up to 15 24HRs per participant. The hs-CRP was measured in blood samples collected at baseline and each of the four quarterly measurement points. Multivariable linear mixed models were used to examine the cross-sectional and longitudinal associations of GI, GL, and hs-CRP. Results Among 582 adult men and women with at least two measurements of diet and hs-CRP, average daily GI score (white bread = 100) was 85 and average GL was 198, and average hs-CRP was 1.84 mg/L. Overall, there was no association between GI or GL and hs-CRP. Subgroup analyses revealed an inverse association between GL and hs-CRP among obese individuals (body mass index ≥30 kg/m2). Conclusion Quality of dietary carbohydrates does not appear to be associated with serum hs-CRP levels. Among obese individuals, higher dietary GL appears to be related to lower hs-CRP levels. Due to the limited number of studies on this topic and their conflicting results, further investigation is warranted.