Dietary inflammatory index and inflammatory markers in Brazilian adolescents.

Objective: To evaluate the association between the inflammatory potential of the diet measured by the energy-adjusted diet inflammatory index (E-DII) and inflammatory markers in adolescents.

Methods: This cross-sectional study was conducted among 518 adolescents aged 18 and 19 years from São Luís, Maranhão, Brazil in 2016. A semiquantitative food frequency questionnaire (FFQ) was used to assess dietary intake from which E-DII scores were calculated to determine the inflammatory potential of the diet. The associations between E-DII and inflammatory markers (hs-CRP, IL-6, IL-4, TNF-α, and IFNγ) were analyzed using multivariable linear regression. The variables included in the adjusted model were identified using the directed acyclic graph.

Results: The diet of these adolescents was mostly pro-inflammatory; mean E-DII score was 1.71 and ranged from -2.44 to 5.58. Higher E-DII scores were positively associated with higher levels of IFNγ in the adjusted analysis (Adjusted Coef.: 1.19; 95%CI: 0.36-12.04). We observed no associations between E-DII and other inflammatory markers (hs-CRP, IL-6, IL-4, TNF-α). Study results indicate that E-DII is useful in evaluating the inflammatory potential of the diet of Brazilian adolescents.

Conclusions: Cross-sectionally E-DII scores were positively associated with IFNγ concentrations. Future research should examine the association between changes in E-DII scores and levels of inflammatory markers longitudinally.