Impact of bacterial probiotics on obesity, diabetes and non-alcoholic fatty liver disease related variables: a systematic review and meta-analysis of randomised controlled trials

Abstract

ObjectiveTo systematically review the effect of oral intake of bacterial probiotics on 15 variables related to obesity, diabetes and non-alcoholic fatty liver disease.DesignSystematic review and meta-analysis.Data sourcesMedline, EMBASE and COCHRANE from 1990 to June 2018.Eligibility criteriaRandomised controlled trials (≥14 days) excluding hypercholesterolaemia, alcoholic liver disease, polycystic ovary syndrome and children <3 years.ResultsOne hundred and five articles met inclusion criteria, representing 6826 subjects. In overweight but not obese subjects, probiotics induced improvements in: body weight (k=25 trials, d=−0.94 kg mean difference, 95% CI −1.17 to −0.70, I²=0.0%), body mass index (k=32, d=−0.55 kg/m², 95% CI −0.86 to −0.23, I²=91.9%), waist circumference (k=13, d=−1.31 cm, 95% CI −1.79 to −0.83, I²=14.5%), body fat mass (k=11, d=−0.96 kg, 95% CI −1.21 to −0.71, I²=0.0%) and visceral adipose tissue mass (k=5, d=−6.30 cm², 95% CI −9.05 to −3.56, I²=0.0%). In type 2 diabetics, probiotics reduced fasting glucose (k=19, d=−0.66 mmol/L, 95% CI −1.00 to −0.31, I²=27.7%), glycated haemoglobin (k=13, d=−0.28 pp, 95% CI −0.46 to −0.11, I²=54.1%), insulin (k=13, d=−1.66 mU/L, 95% CI −2.70 to −0.61, I²=37.8%) and homeostatic model of insulin resistance (k=10, d=−1.05 pp, 95% CI −1.48 to −0.61, I²=18.2%). In subjects with fatty liver diseases, probiotics reduced alanine (k=12, d=−10.2 U/L, 95% CI −14.3 to −6.0, I²=93.50%) and aspartate aminotransferases (k=10, d=−9.9 U/L, 95% CI −14.1 to -5.8, I²=96.1%). These improvements were mostly observed with bifidobacteria (Bifidobacterium breve, B. longum), Streptococcus salivarius subsp. thermophilus and lactobacilli (Lactobacillus acidophilus, L. casei, L. delbrueckii) containing mixtures and influenced by trials conducted in one country.ConclusionsThe intake of probiotics resulted in minor but consistent improvements in several metabolic risk factors in subjects with metabolic diseases.Trial registration numberCRD42016033273.

A randomised controlled study shows supplementation of overweight and obese adults with lactobacilli and bifidobacteria reduces bodyweight and improves well-being

“…Our study is one of the first to report the impact of a multi-strain probiotic on weight loss in response to 6-months supplementation in a cohort of healthy, overweight and obese, free-living (no dietary or lifestyle restrictions) subjects. More weight loss occurred in the overweight subjects (SG1a) compared with the obese (SG1b) receiving probiotics agreeing with the meta-analysis findings of Koutnikova and colleagues of greater weight loss in probiotic supplemented overweight participants than obese 10 . No weight loss was observed at the midpoint (3 months) of our study as has been shown in a number of short-term probiotic studies in free-living overweight/ obese subjects [18][19][20] .…”

Risk factors associated with canine overweightness and obesity in an owner-reported survey

“…This finding is specific to probiotics among other supplements reported in the survey, and the effect persists in a sample composed of dogs without major reported health issues. This relationship is supported by work that shows significant differences in the gut microbiota of normal and obese dogs (23), as well as recent reviews and meta-analyses of experimental and clinical trials of probiotic supplementation in different species (24)(25)(26). However, to the best of our knowledge this is the first large cross-sectional demographic study that has specifically identified probiotic supplementation as a potential protective factor with regard to overweightness and obesity.…”

The Gut Microbiota and Its Metabolites, Novel Targets for Treating and Preventing Non‐Alcoholic Fatty Liver Disease

“…[129] A meta-analysis demonstrated that subjects with NAFLD had a consistently lower body mass index (BMI) and fat content after supplementation with Bifidobacterium. [130] Another randomized clinical trial suggested that the VSL#3 probiotic plays a beneficial role in ameliorating childhood obesity and NASH, decreasing BMI, and increasing the GLP-1 level. [131] This liver protective effect was also demonstrated in several rodent experiments.…”