We have reported that glucomannan can be of great benefit in the treatment of diabetics by reducing serum cholesterol levels, decreasing postprandial glycemia, reducing 24-hour urinary glucose and decreasing the dosage of insulin. However, previous studies have suggested that the effects of glucomannan might be greater when it is used in a gelled form. We therefore compared the effects of glucomannan supplements in 50 g OGTT and a test meal in normal subjects.
The mean blood glucose and insulin levels with standard OGTT supplemented with 3.9g glucomannan in three different ways (non-gelled, gelled or mixed into glucose solution) were less than those of the standard OGTT. However, there were no significant differences among these groups.
On addition of 3.9 g glucomannan to the test meal, glucomannan caused a marked decrease in the mean blood glucose and insulin level compared to the OGTT groups. When 3.9 g glucomannan was incorporated into the food (butter and corn soup), the mean blood glucose and insulin levels were more significantly reduced than those in the case of taking 3.9g glucomannan 15 min before the test meal.
It is suggested therefore that glucomannan should be intimately mixed with the food for the management of diabetics as well as guar gum and pectin.