Comparing effectiveness of fat burners and thermogenic supplements to diet and exercise for weight loss and cardiometabolic health: Systematic review and meta-analysis

Abstract

Background: Those who are overfat face an onslaught of advice for losing weight, including using dietary supplements that purport to have fat burning capabilities to achieve a reduced body mass, fat mass and improvement in cardiometabolic health in combination with exercise or diet and exercise regimens. Aim: To examine long-term effectiveness of supplements for both weight loss and improvements in cardiometabolic health for these individuals. Methods: A PRISMA methods of systematic review was conducted from August 2018 through January 2019 using Medline, PubChem, PubMed, EBOSCO CINHAL and SPORTDiscus, and Google Scholar yielding 23,441 returns of which 21 studies (duration greater than 8 weeks with participant populations of BMI greater than 24.9) were included for meta-analysis. Meta-analysis examined pooled effect size and 95% confidence interval for: body mass, fat mass, fat-free mass, total cholesterol, high-density lipoproteins, low-density lipoproteins, resting metabolic rate. Intra-study effect sizes were compared with previously reported results for diet or diet and exercise in a 2x2 chi-square analysis for the number of studies that induced effects greater than or less than the effect size. Results: There is a general trend to show effectiveness (effect size greater than 0.00) for obtaining beneficial changes from use of thermogenic dietary supplements, yet the 95% confidence interval for effect size crossed 0.00 (indicating no benefit). Chi-square comparison to exercise, or combination of diet and exercise, indicates that responses induced from weight-loss supplements were less effective than what is obtained from utilizing exercise, or diet and exercise, without additional weight-loss supplements. Conclusion: There appears to be limited benefit that may be derived from the inclusion of thermogenic dietary supplements to reduce body mass and improve cardiometabolic health for individuals who are overfat.