A meta-analysis was conducted to examine the effect of probiotics on body weight and glycaemic control in overweight or obese adults. Adults who received probiotics had significant reductions in body weight, BMI, waist circumference, fat mass percentage compared with adults in the control group (Wang et al., 2019b). A greater reduction in fat mass was observed with 1) use of high versus low doses of probiotics, 2) probiotics of a single strain versus multiple strains, and 3) probiotics administered in the form of foods compared with capsules or powder. In addition, when compared with the control group, individuals in the probiotic groups had reduced insulin levels. Overall, Wang et al. (2019b) and Koutnikova et al. (2019) claim that use of probiotics both has a positive effect on weight loss and improves other metabolic parameters.
A) Increased insulin levels
B) Reduced insulin levels
C) No effect on insulin levels
D) Indeterminate effect on insulin levels