Effects of probiotic supplementation in patients with type 2 diabetes: systematic review and meta-analysis

Context: The rising prevalence of type 2 diabetes requires increased efforts to find effective therapeutic agents for this complex condition. Following the recent observation that the gut microbiota is altered in diabetic patients, researchers investigated the effect of probiotics in patients with diabetes. Objective: The aim of this systematic review was to assess the effects of probiotic consumption on glycemic control in diabetic patients. Data Sources: PubMed, Scopus, Web of Science (formerly ISI Web of Knowledge), Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, and ProQuest Dissertations and Theses databases were searched up to November 2015. Study Selection: Clinical trials in diabetic patients in whom probiotics were administered as an intervention were included. Data Extraction: Primary outcomes were fasting blood glucose, insulin concentration, insulin resistance, and hemoglobin A1c. Secondary outcomes were adverse events. Data Synthesis: Of the 2736 reports that were screened, 13 clinical trials met the inclusion criteria. Pooling data from eligible clinical trials revealed that probiotic supplementation significantly (P<0.05) decreased fasting blood glucose and hemoglobin A1c in diabetic patients, although the participants' characteristics (eg, body mass index) and the number and type of probiotic microorganisms affected the clinical response. Conclusions: Administration of probiotics appears to have a beneficial role in the management of type 2 diabetes; however, more clinical studies with adequate sample sizes and sound methodology are required to inform the development of evidence-based treatment guidelines.