Effectiveness of dietary, physical activity, and lifestyle interventions on weight and cardiometabolic outcomes in adults with overweight or obesity: an umbrella review of 112 systematic reviews and meta-analyses from 50 countries
Umbrella review demonstrates superior cardiometabolic and weight benefits from combined diet and exercise in adults with obesity, highlighting the value of multicomponent interventions.
Key Points
To systematically appraise and compare the effectiveness of dietary, physical activity, and lifestyle interventions across multiple treatment durations on weight, BMI, and cardiometabolic outcomes in adults with overweight or obesity.
Conducted an umbrella review and meta-analysis of systematic reviews and meta-analyses of randomized controlled trials across 50 countries from PubMed searches (2015–2025; PROSPERO CRD420251245029).
Evaluated 112 reviews comprising 424 comparisons and 2,332 unique randomized controlled trials using AMSTAR 2 for quality and GRADE for certainty of evidence.
Analyzed primary outcomes of weight and BMI change across follow-up durations (<3, 3–6, 6–12, and >12 months) and secondary cardiometabolic outcomes using random-effects models.
Combined diet and physical activity achieved the largest weight reduction at >12 months (mean difference −3.68 kg; 95% CI: −5.47, −1.89) and largest BMI reduction at <3 months (−1.22 kg/m²; 95% CI: −2.31, −0.13), as well as the greatest improvements in fasting glucose and insulin resistance.
Physical activity alone produced the greatest reduction in systolic blood pressure at 6–12 months (mean difference −6.10 mm Hg; 95% CI: −8.07, −4.13), whereas effects on lipids remained inconsistent across modalities.
Statistical heterogeneity was substantial across pooled estimates (I² commonly 70%–99%), and AMSTAR 2 methodological confidence was rated low or critically low in 69% of included reviews.