A study from the University of Pittsburgh (ID# 0195) that is being presented as an oral presentation this morning at SLEEP 2008 takes a deeper look at the relationship between short sleep duration and obesity. The study concludes that a core aspect of this association may be reduced amounts of rapid eye movement (REM) sleep.
The study involved 335 children and teens between the ages of seven and 17 years. Sleep was measured by polysomnography for three consecutive nights. Compared with normal-weight children, overweight children slept about 22 minutes less per night.
Overweight children also had shorter REM sleep periods, lower REM activity and density, and longer latency to the first REM period. After adjusting for other factors, one hour less of REM sleep increased the risk of being overweight by about three times, while one hour less of total sleep increased the odds of overweight by about two times.
According to the American Academy of Sleep Medicine, the complex process of sleep involves multiple stages that make up a sleep cycle. Most adults will go through four to six cycles in a full night of sleep. REM sleep tends to be the final stage of the sleep cycle in normal adult sleep.
The SLEEP 2008 abstract book is available online at http://www.journalsleep.org/PDF/AbstractBook2008.pdf.