Glucose tolerance and ageing.

Hyperglycaemia, impaired glucose tolerance and noninsulin dependent diabetes become progressively more common with advancing age. The mechanism is insensitivity to the actions of insulin at the postreceptor level. Inadequate secretion of insulin and decreased hepatic sensitivity to insulin's action in suppressing glucose output also occur. The age-related changes may be made worse by obesity, renal failure or the ingestion of certain drugs, or may be lessened by increased physical activity.