Expansion of human alpha-cell area is associated with a higher maximum body mass index before the onset of type 2 diabetes

Highlights We examined whether maximum body mass index (BMI) before the onset of diabetes (MBBO) affects histological findings of islet cells. We divided patients into two groups according to an MBBO cutoff of 25 kg/m2 or BMI cutoff of 21 kg/m2. We compared immunohistochemical parameters between the MBBO groups or BMI groups. The relative alpha‐cell area in the high MBBO group was significantly higher than that in the low MBBO group. There was no difference in the other parameters between the MBBO groups or BMI groups.