[Effect of fructose and sorbitol on insulin-induced hypoglycemia]

Twelve metabolically normal subjects were given 0.325 g/kg fructose or glucose dissolved in water 30 minutes after intravenous infusion of insulin, 0.05 U/kg. Blood glucose concentration was then measured for up to 60 minutes or until the onset of hypoglycaemia (study I). In study II two bread units (BU) were given to six subjects in the form of dark bread, as well as 12 g of butter and water. In two other groups, of six subjects each, 1 BU was substituted either by fructose or sorbitol. Seven subjects who had been given insulin but only water to drink afterwards served as the control group. In study I, both glucose and fructose achieved a clear slowing in the blood-sugar drop compared with the control group. But with glucose there was initially a slight rerise and the final hypoglycaemic level was somewhat delayed. This minor difference between glucose and fructose was not demonstrable in study II with the addition of fat and carbohydrate substitution. Each carbohydrate combination similarly influenced the course of blood sugar concentration. The results indicate that diabetics should continue to be given glucose rather than fructose or sorbitol if hypoglycaemia occurs. On the other hand, both fructose and sorbitol, although acutely less effective in raising blood glucose concentration, do counteract as carbohydrates the development of insulin-induced hypoglycaemia.