ABSTRACT
Objective: This study evaluated the effect of microbiome-targeted therapies (pre-, pro-, and synbiotics) on weight loss and other anthropometric outcomes when delivered as an adjunct to traditional weight loss interventions in overweight and obese adults. Methods: A systematic review of three databases (Medline [PubMed], Embase, and the Cochrane Central Register of Controlled Trials) was performed to identify randomized controlled trials published between January 1, 2010 and December 31, 2020, that evaluated anthropometric outcomes following microbiome-targeted supplements in combination with dietary or dietary and exercise interventions. The pooled mean difference (MD) between treatment and control groups was calculated using a random effects model. Results: Twenty-one trials with 1233 adult participants (76.4% female) with overweight or obesity were included. Separate meta-analyses were conducted for probiotics (n=11 trials) and synbiotics (n=10 trials) on each anthropometric outcome; prebiotics were excluded as only a single study was found. Patient characteristics and methodologies varied widely between studies. All studies incorporated some degree of caloric restriction, while only six studies included recommendations for adjunct exercise. Compared with dietary or dietary and exercise interventions only, probiotics resulted in reductions in body weight (MD: -0.73 kg; 95% confidence interval [CI]: -1.02 to -0.44, p < 0.001), fat mass (MD: -0.61 kg; 95% CI: -0.77 to -0.45; p<0.001) and waist circumference (MD: -0.53 cm; 95% CI: -0.99 to -0.07, p=0.024) while synbiotics resulted in reductions in fat mass (MD: -1.53 kg; 95% CI: -2.95 to -0.12, p=0.034) and waist circumference (MD: -1.31 cm; 95% CI: -2.05 to -0.57, p<0.001). Conclusion: This analysis indicates that microbiome-targeted supplements may enhance weight loss and other obesity outcomes in adults when delivered as an adjunct to dietary or dietary and exercise interventions. Personalized therapy to include microbiome-targeted supplements may help to optimize weight loss in overweight and obese individuals.