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(R)). Predictors of the DII in children (C-DII (TM)) 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 < 0.05), whereas breastfeeding and family meals at home were associated with a more anti-inflammatory diet (P < 0.04). Higher maternal, but not paternal, E-DII scores during pregnancy (P < 0.001) and at 5-year follow-up (P = 0.008) were associated with more pro-inflammatory diet at age 5. Results from the mediation analysis suggest that maternal grandmothers E-DII scores may influence C-DII indirectly via the mothers E-DII scores. Conclusions: A more pro-inflammatory dietary score was associated with childhood overweight and obesity. Parental, familial and personal factors independently influenced the C-DII score. (C) 2019 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.