Weight management using meal replacements and cardiometabolic risk reduction in individuals with pre-diabetes and features of metabolic syndrome: A systematic review and meta-analysis of randomized controlled trials

This review synthesized the evidence from randomized controlled trials comparing the effect of meal replacements (MRs) as part of a weight loss intervention with conventional food-based weight loss diets on cardiometabolic risk in individuals with pre-diabetes and features of metabolic syndrome. MEDLINE, EMBASE, and Cochrane Library were searched through January 16, 2024. Data were pooled using the generic inverse variance method and expressed as mean difference [95% confidence intervals]. The overall certainty of the evidence was assessed using GRADE. Ten trials (n = 1254) met the eligibility criteria. MRs led to greater reductions in body weight (-1.38 kg [-1.81, -0.95]), body mass index (BMI, -0.56 kg/m2 [-0.78, -0.34]), waist circumference (-1.17 cm [-1.93, -0.41]), HbA1c (-0.11% [-0.22, 0.00]), LDL-c (-0.18 mmol/L [-0.28, -0.08]), non-HDL-c (-0.17 mmol/L [-0.33, -0.01]), and systolic blood pressure (-2.22 mmHg [-4.20, -0.23]). The overall certainty of the evidence was low to moderate owing to imprecision and/or inconsistency. The available evidence suggests that incorporating MRs into a weight loss intervention leads to small important reductions in body weight, BMI, LDL-c, non-HDL-c, and systolic blood pressure, and trivial reductions in waist circumference and HbA1c, beyond that seen with conventional food-based weight loss diets.