A composition for use in the treatment of type 2 diabetes and its complications, wherein the composition comprises Lactobacillus reuteri GMNL-89 with the deposition numbers of BCRC 910340 and CCTCC M 207154. Preferably the Lactobacillus reuteri GMNL-89 comprises at least one or live bacteria, dead bacteria and supernatant of bacterial cell cultures. A composition for the treatment of inhibiting high blood glucose levels, high glycosylated haemoglobin ratios, high total cholesterol levels, high liver triglyceride concentrations, high low density lipoprotein (LDL), high hemostasis model assessment (HMA) indicator, high tumor necrosis factor α (TNF-α), high interleukin-1 β (IL-1β) or high interleukin-6 (IL-6) comprising administering a probiotic composition, wherein the probiotic bacterial strain comprises Lactobacillus reuteri GMNL-89 with a deposition number of CCTCC M 207154 is also outlined. A composition for the treatment of increasing high density lipoprotein (HDL), the activity of superoxide dismutase (SOD) or the activity of glutathione peroxidise (GSH-Px) comprising administering a probiotic bacterial strain wherein the probiotic bacterial strain comprises Lactobacillus reuteri GMNL-89 with a deposition number of CCTCC M 207154 is provided.
