Washington, Aug 11 - Insufficient sleep may trigger insulin resistance and reduced glucose tolerance, which increases the long-term risk of diabetes, according to a new study.

Today, many Americans sleep fewer than six hours each night and individuals who report insufficient sleep have in previous studies demonstrated an increased risk of developing diabetes.

This new study examined whether reduced sleep duration itself may increase the risk of developing diabetes when combined with physical inactivity and overeating.

Researchers subjected a group of healthy middle-aged men and women to two controlled 14-day periods of sedentary living with free access to food and 5.5 or 8.5 hours of sleep.

When the subjects had their bed time decreased from 8.5 hours to 5.5 hours they showed changes in their response to two common sugar tests, which were similar to those seen in people with an increased risk of developing diabetes.