Introduction: Various pathogenesis and daily increase in number of diabetic patients, emphasizes the necessity of finding new therapeutic methods. Nowadays, physicians focus on controlling the blood sugar, although the protections against diabetic complications like: retinopathy, nephropathy and neuropathy are being ignored. Several studies on diabetic patients suggest that thiamine metabolism in diabetic is deficient. Thiamine(vitamin B1) is an essential cofactor of several enzymes involved in carbohydrates metabolism. Therefore, the aim of this study is to review the physiological role of thiamine in metabolism of glucose and the effectiveness of thiamine on lowering the secondary diabetes complication.

Materials and Methods: The study is done by searching the English and Persian databases like: Pubmed, Scopus, Proquest, Google scholar, SID, Magiran and Iranmedex with the terms: thiamine, diabetes, retinopathy, neuropathy and nephropathy between the years 1988 till 2015. Among 50 related articles, 38 with the full text access were included.

Results: Thiamine blocks many harmful hyperglycemia-pathway like: hexosamine pathway, AGE formation, PKC activation; though it increases the activation of transketolase enzyme. Thus thiamine is a good therapeutic option.