Endocrinologists at the University of Chicago say that lack of sufficient sleep may contribute to insulin resistance and decreased glucose tolerance, two conditions that up the long-term risk of developing type 2 diabetes.
Their study, which will be published in The Endocrine Society’s Journal of Clinical Endocrinology & Metabolism, says that lack of sufficient sleep is common in Western societies and is often accompanied by overeating and too sedentary a lifestyle.
Researchers studied healthy middle-aged men and women over two controlled 14-day periods in which they lived under controlled conditions: They were required to be sedentary and not engage in physical activity; they had free access to as much food as they wanted; and their sleep times were reduced from 8.5 hours per night to 5.5 hours.
They then administered two common blood tests to the subjects after their sleep times had been reduced. They found changes that were similar to those seen in people who have been diagnosed as at-risk for developing type 2 diabetes.
Exactly how shortened sleep times lead to insulin resistance and lowered glucose tolerance is unclear. The scientists acknowledge that their study sample and duration was too small, and that what they found will have to be confirmed by a much larger test.
However, they believe that lack of sufficient sleep will soon join lack of exercise and overeating as one of the factors that are important precursors to type 2.