Predictors of the dietary inflammatory index in children and associations with childhood weight status: A longitudinal analysis in the Lifeways Cross-Generation Cohort Study

BACKGROUND & AIMS: The family environment can influence offspring diet and weight status. Obesity is a pro-inflammatory state, which is associated with the dietary inflammatory index (DII®). Predictors of the DII in children (C-DII™) and its associations with childhood obesity are relatively unknown. We evaluated the intergenerational relationships between the energy-adjusted DII (E-DII) scores in adults, predictors of C-DII and associations with childhood weight status. METHODS: The study comprises 551 children and index-child's mothers, fathers and grandparents in the Lifeways Cross-Generation Cohort Study. E-DII scores were generated at baseline for expectant mothers, fathers, and grandparents, and at 5-year follow-up for the mothers and children, using a validated food frequency questionnaire. Body mass index (BMI) and waist circumference were determined at age 5 and 9 years. Associations were assessed by logistic regression and mediation analysis. RESULTS: Higher C-DII scores indicating a more pro-inflammatory diet among children, were associated with greater risk of childhood obesity at age 5 (OR:1.09; 95%CI:1.00-1.37; P = 0.02) and overweight/obese status at 5 and 9 years (OR:1.06; 95%CI:1.01-1.09; P = 0.01 and OR:1.12; 95%CI:1.07-1.18; P = 0.01, respectively). Maternal and paternal smoking during pregnancy (OR:1.98; 95%CI:1.19-3.03; P = 0.001 and OR:1.64; 95%CI:1.12-2.49; P = 0.006, respectively) increased likelihood of higher C-DII at age 5. Child BMI, TV watching and all meals given by the childcare provider were associated with a more pro-inflammatory diet (P