Recent evidence supports detrimental effects of advanced glycation endproducts (AGE) on vascular function (VF). Though, the effect of AGE-modified proteins alone on vascular function remained unknown. Therefore, the aim of our study is to investigate the effects of heat-treated, glycated beta-lactoglobulins (BLG) on vascular function in subjects with type 2 diabetes mellitus (T2DM) and to compare it to non-glycated, heat-treated BLG.