Objectives: Very Low-Energy Diets (VLEDs) lead to rapid weight loss in adults. This systematic review aimed to evaluate the efficacy and safety of VLEDs for weight loss in children and adolescents with obesity.
Methods: A systematic literature search of six health and medical databases was conducted in November 2017. Eligible studies were in English, studied a VLED providing ≤800kcal/day(3350kJ) or <50% daily estimated energy requirements in children and adolescents (≤18-years) with obesity and reported at least one weight-related outcome. Quality appraisal was conducted using The Academy of Nutrition and Dietetics quality criteria checklist and study data extracted. Meta-analysis was performed using Comprehensive Meta-Analysis software.
Results: Twenty-four studies met inclusion criteria and were included (16 pre-post studies, 4 non-randomised comparison studies, 2 randomised controlled trials, 2 chart reviews). The VLED intervention duration ranged from 3-24 weeks. Meta-analysis of 20 studies reporting the effect of VLED intervention on weight outcomes indicated a mean 8.1kg weight loss (95% confidence interval [CI]: 7.1 to 9.0kg, p<0.001) post-intervention. Adolescent-only studies (10-18 years) had greater weight loss compared to child and adolescent studies (17.7kg, CI: 9.9 to 25.6kg, p<0.001, n=4 versus 7.9kg, CI: 7.0 to 8.9kg, p<0.001, n=16). Meta-analysis of seven studies reporting weight at follow-up (up to 14.5 months from baseline) indicated mean 5.2kg weight loss (CI: 2.7 to 7.7kg, p<0.001) from baseline. Only 12 studies reported intervention side-effects, five reported no adverse effects and seven reported mild side effects, including fatigue, hunger, nausea.
Conclusions: Current evidence suggests VLEDs are safe and effective for treating children and adolescents with obesity. Compared with traditional dietary interventions, VLEDs appear to be more effective for weight loss, although further studies in children are warranted . Future studies should determine strategies for maintaining weight loss following a VLED intervention and comprehensively assess adverse effects associated with VLED adherence.