Low-Carbohydrate Diets for the Management of Pediatric Obesity: A Systematic Review and Meta-analysis

Although low-carbohydrate (LC) diets have been shown to be beneficial for weight loss and improvements in cardiometabolic health in adults with obesity, their efficacy in youth has not yet been established.

A systematic review and meta-analysis was conducted to qualitatively and quantitively synthesize the evidence from clinical trials testing the efficacy of LC diets to improve anthropometric and cardiometabolic-related parameters in children and adolescents with obesity.

Searches in Medline, EMBASE, and Cochrane databases were undertaken for LC interventions with or without control comparisons.

Data before and after the LC intervention and control comparisons (if applicable) were extracted from 19 studies, 17 of which were pooled in random-effects meta-analyses.

Children on LC diets (Mean = 30 [IQR: 30-60] g/d), for approximately 3 months (IQR: 3-4 months) significantly reduced their weight (mean change [MC] = -7.09 [95% CI: -9.60, -4.58] kg; P < .001), body mass index (BMI) (MC = -3.01 [-3.71, -2.30] kg/m2; P < .001), and BMI z-score (MC = -0.27 [-0.48, -0.06]; P = .020), on average, with concomitant improvements in different metabolic biomarkers, such as serum triglycerides (MC = -29.16 [-45.06, -13.26] mg/dL; P = .002) and insulin (MC = -7.13 [-9.27, -4.99] µU/mL; P < .001). Evidence from 5 out of 7 controlled trials suggests that LC diets without caloric restriction may lead to similar or greater improvements in anthropometric and lipid-related outcomes relative to caloric-restricted or low-fat diets. However, meta-analyses demonstrated high between-study heterogeneity, indicative of a wide variety of methodologies, including intervention duration and degree of carbohydrate restriction.

Overall, this review found that short-term LC diets can be beneficial for weight loss and improving cardiometabolic parameters with or without calorie restriction. However, the limited number of controlled trials and the demonstrable diversity in methods prevent firm conclusions regarding their efficacy relative to traditional approaches, such as energy restriction.

PROSPERO registration no. CRD42023440835.