Role of probiotics in glycemic controls and body weight in type 2 diabetes: a systematic of human and animal studies

Publications evaluating the effects of probiotics on glycemic parameters, body weight change and food intakes have increased steadily in recent years. This study hence assessed all related human and animal studies. In the present systematic review, we used search engines to collect relevant data until May 2014, concerning the effects of probiotics on body weight changes, fasting plasma glucose [FPG], oral glucose tolerance test [OGTT], glycated hemoglobin [HbA1c], insulin, and insulin resistance in T2DM. Twenty-five animal and four human articles met our inclusion criteria, articles which generally reported positive effects of probiotics on glycemic parameters. Lactobacillus sub-strains were used in all studies except for one. Most of the human and animal studies reported significant reduction in FPG and delay in the onset of T2DM, respectively; only animal studies reported significant reduction in OGTT. Few studies showed significant reduction and increase in HbA1c and insulin levels, respectively. Most studies reported significant increment in body weight after intervention, whereas only a few reported significant reductions in this parameter. This study showed that the administration of probiotics have beneficial effects on glycemic parameters, although their effects on body weight were inconsistent. Therefore, considering the controversial results among human and animal reports, more data evidence is needed to conduct a meta-analysis