Published online by Cambridge University Press: 26 August 2025

The dietary inflammatory index (DII) has emerged as a promising tool associated with the development of cardiovascular risk factors. This systematic review and meta-analysis, developed in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines (the protocol was registered in the International Prospective Register of Systematic Reviews (PROSPERO) under number CRD42022323267), aimed to synthesise observational studies that evaluated the association between the DII and indicators of body adiposity and blood pressure in children and adolescents. PubMed/MEDLINE, Embase, LILACS, CINAHL, Web of Science, Scopus and Google Scholar were searched, without time and language restrictions. The methodological quality of the studies and the certainty of the evidence were assessed using the Newcastle–Ottawa scale and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach, respectively. The meta-analysis revealed that a higher DII (pro-inflammatory diet) was significantly associated with increased odds of body adiposity, as indicated by body mass index (BMI) (odds ratio [OR] = 1·62; 95% confidence interval [CI] 1·38–1·86), waist circumference (OR = 1·45; 95% CI 1·10–1·81) and the waist-to-height ratio (OR = 1·76; 95% CI 1·38–2·14) in adolescents, compared with those with a lower DII (anti-inflammatory diet). In addition, for every unit increase in the DII, there was a small but significant rise in mean BMI (β = 0·06 kg/m2). The children’s dietary inflammatory index (CDII) showed no association with cardiometabolic risk factors. There were no consistent associations between the DII or CDII and blood pressure. In conclusion, while a pro-inflammatory diet (based on the DII) is linked to body adiposity, additional longitudinal studies are needed to explore these associations, particularly regarding the CDII and blood pressure.