The effect of diet or exercise on ectopic adiposity in children and adolescents with obesity: a systematic review and meta-analysis

Abstract

Objective: Ectopic fat depostion in youth with obesity is associated with anincreased cardiovascular disease risk. The aim of this meta‐analysis was tosummarize the evidence for the use of diet and/or exercise on ectopic adiposity inthis population.Methods: A systematic literature search was performed according to thePreferred Reporting Items for Systematic Reviews and Meta‐analysis statement.Clinical trials that assessed ectopic fat deposition and included study arms with dietand/or exercise were searched in PubMed, PEDro and the Cochrane database.Results: Hepatic fat content and intramyocellular lipid content were described innine studies and three studies, respectively. Most studies included teenagers, andstudy duration ranged between 3 and 12 months without follow‐up. Usingrandom‐effects weights, the standardized mean difference of the change in hepaticadiposity (totalling 320 subjects) was −0.54 Hedges’ g (95% confidence interval:−0.69 to −0.38 with p < 0.0001). By re‐expressing this effect size, it is seen that dietand/or exercise results in an absolute reduction of intrahepatic lipid with 2%,which accords with a relative reduction up to 70%. Although there were significantameliorations of insulin sensitivity, no significant changes in intramyocellular lipidwere observed.Conclusions: This meta ‐ analysis showed that diet and/or exercise is effective toreduce hepatic adiposity in youth with obesity.