June 19, 2013
Sleeping In On The Weekend May Ward Off Type 2 Diabetes
Rebekah Eliason for redOrbit.com - Your Universe Online
For men who are losing sleep during the week, lowering the risk for type 2 diabetes may be as simple as catching a few extra hours of sleep on the weekend.A recent study lead by Peter Liu, MD, PhD, a researcher at Harbor-UCLA´s LA BioMed center, found that after only 3 days of “catch-up sleep” men with long-term weekday sleep restriction substantially improved their insulin sensitivity. The body´s sensitivity to insulin directly correlates to how well glucose, or blood sugar, is cleared from the blood stream.
"We all know we need to get adequate sleep, but that is often impossible because of work demands and busy lifestyles," said Liu. "Our study found extending the hours of sleep can improve the body's use of insulin, thereby reducing the risk of Type 2 diabetes in adult men. Reducing the incidence of this chronic illness is critical for a nation where diabetes affects nearly 26 million people and costs an estimated $174 billion annually."
Insulin is a hormone produced in the pancreas that regulates the body´s blood sugar levels. A person with type 2 diabetes becomes resistant to the effects of insulin. Consequently, blood sugar levels are not effectively regulated by the amount of insulin produced. Risk for developing type 2 diabetes, the seventh leading cause of death in the United States, can be greatly reduced by maintaining the body´s natural sensitivity to insulin.
Other studies demonstrate the harmful effects on insulin sensitivity during experimental sleep deprivation in healthy normal sleepers. New information is presented in this study about people who lose sleep during the week, often due to jobs and busy schedules, and catch up later on the weekend.
Liu and colleagues from the University of Sydney studied nineteen non-diabetic men with an average age of 28.6 years old who had self-reported inadequate sleep during the work week for six months or longer. Each man received on average of only 6.2 hours of sleep each work night but regularly increased their sleep on the weekends by 37.4 percent, or 2.3 hours per night. A small device to monitor sleep-wake cycles was worn by each participant to verify their reported sleep times.
All participants spent three consecutive nights in a sleep lab on two separate weekends. Men were randomly assigned to two of three sleep conditions: ten hours of sleep, six hours of sleep or ten hours in bed interrupted by noises loud enough to rouse them from deep sleep but quiet enough to not wake them completely.
The six-hour sleep conditions were designed to test persistent sleep restriction.
Liu explained that during the study, each person consumed the same amount of food to eliminate diet as a factor in the results. On the fourth morning, each participant´s blood was drawn to test their blood sugar and insulin levels to calculate their insulin sensitivity.
Those who slept ten hours every night were found to have much higher insulin sensitivity than when they slept for only six hours. Insulin resistance scores also decreased when sleep was extended, demonstrating that those few extra hours of snoozing could have a positive impact on the body´s ability to naturally regulate its blood sugar levels.
The study was funded by the National Institutes of Health's National Center for Advancing Translational Sciences and from Australia's National Health and Medical Research Council.