RESUMO
BACKGROUND: 70% of children with obesity and overweight live in low-income and middle-income countries. Several interventions have been done to reduce the prevalence of childhood obesity and prevent incident cases. Hence, we did a systematic review and meta-analysis to determine the effectiveness of these interventions in reducing and preventing childhood obesity. METHODS: We conducted a search for randomised controlled trials and quantitative non-randomised studies published on MEDLINE, Embase, Web of Science, and PsycINFO databases between Jan 1, 2010, and Nov 1, 2022. We included interventional studies on the prevention and control of obesity in children up to age 12 years in low-income and middle-income countries. Quality appraisal was performed using Cochrane's risk-of-bias tools. We did three-level random-effects meta-analyses and explored the heterogeneity of studies included. We excluded critical risk-of-bias studies from primary analyses. We assessed the certainty of evidence using the Grading of Recommendations Assessment, Development, and Evaluation. FINDINGS: The search generated 12â104 studies, of which eight studies were included involving 5734 children. Six studies were based on obesity prevention, most of which targeted behavioural changes with a focus on counselling and diet, and a significant reduction in BMI was observed (standardised mean difference 2·04 [95% CI 1·01-3·08]; p<0·001). In contrast, only two studies focused on the control of childhood obesity; the overall effect of the interventions in these studies was not significant (p=0·38). The combined studies of prevention and control had a significant overall effect, with study-specific estimates ranging between 0·23 and 3·10, albeit with a high statistical heterogeneity (I2>75%). INTERPRETATION: Preventive interventions, such as behavioural change and diet modification, are more effective than control interventions in reducing and preventing childhood obesity. FUNDING: None.