Introduction
Lifestyle interventions, including diet, are effective for treating childhood obesity in the short to medium-term however the optimal macronutrient distribution of the diet is unknown. This systematic review examined the effectiveness of weight management interventions that compared diets with varying macronutrient distributions, on weight outcomes, primarily body mass index, in overweight or obese children and adolescents. Cardiometabolic risks were examined as secondary outcomes.
Methods
Articles from a systematic search of seven databases from 1975 to June 2013 were assessed by two independent reviewers against the following inclusion criteria: randomised or quasi-randomised controlled trial, comparing dietary interventions varying in macronutrient distribution, for weight loss in overweight or obese participants ≤18 years.
Results
Fourteen trials were identified for inclusion examining participants aged 6-18 years. Seven trials compared a low fat diet (≤33% energy or <40g /day) to an isocaloric (n=2) or ad libitum (n=5) low carbohydrate diet (<20% energy or <60g/day). Three studies reported enhanced weight loss in the low carbohydrate diet group immediately post-intervention only, however study quality was poor; cardiometabolic benefits were inconsistent. Six trials comparing increased protein (19-30% energy) to isocaloric standard protein diets (15-20% energy) found no differences in outcomes. The remaining trial comparing an increased fat (40% energy) to an isocaloric standard fat diet (27% energy) with consistent protein content (18% energy) also found no dietary effect on outcomes.
Conclusions
The current evidence suggests that altering the dietary macronutrient distribution has little to no effect on weight loss or cardiometabolic outcomes in overweight or obese children and adolescents. All studies reported weight loss regardless of macronutrient distribution, supporting a primary objective to reduce energy intake.