Background and aims: Recent studies have shown that lifestyle intervention in prediabetes reduces the progression to type 2 diabetes (DM2). However, the impact of meal frequency on glucose metabolism remains unknown. The aim of the study was to compare the effects of two isocaloric meal patterns (three-vs six meals per day) on glucose and insulin levels during an oran glucose tolerance test (OGTT) in subjects with: 1) impaired glucose tolerance (Group-A, 2-hour-blood-glucose: 140-199mg/dL), 2) type 2 diabetes (Group-B) and 3) with 2-hour-blood-glucose: 140-199mg/dl and/or blood-glucose >200mg/dL at 30 or 60 or 90min (Group-C).