Diurnal patterns of oral glucose tolerance in diabetics

Summary Oral glucose tolerance tests were performed in the morning and afternoon in twenty newly diagnosed untreated diabetic patients. Fasting blood glucose levels were significantly higher in the morning than in the afternoon. Blood glucose values after glucose ingestion also tended to be higher in the morning than in the afternoon. This pattern, however, was most marked for the patients with the greatest degrees of hyperglycaemia. It was also more evident in females than males. Serum insulin values did not differ significantly in the morning and afternoon.