Nadirs of oral glucose tolerance tests are independent of age and sex.

We analyzed nadirs of 75-g oral glucose tolerance tests in 400 subjects who remained completely asymptomatic during the test. The median nadir was 63 mg/dl, the 10th percentile 48 mg/dl, and the 2.5th percentile 41 mg/dl. Seventy-five percent of the nadirs occurred at 3-4 h. There were no differences in the absolute level of nadirs between men and women, nor between the subjects 17-30 and 61-74 yr of age.