For years, experts have warned that obesity increases the risk of diabetes, hypertension and heart attack. Now, there's more bad news: Being fat makes it harder to sleep, and sleep deprivation can increase your craving for food.
Recent studies at the Johns Hopkins University and elsewhere show that those who sleep poorly are more likely to have weight problems than sound sleepers, that high-fat diets can alter sleep cycles and that hormones controlling our appetites can rise and fall with the quality of our shut-eye.
"If you don't sleep well tonight, you're going to have trouble driving tomorrow. The question is, is there a bigger payback than that?" said Dr. Naresh Punjabi, a sleep researcher at the Johns Hopkins Bayview Medical Center.
Sleep is an increasingly scarce commodity in today's caffeinated world. Only half of all U.S. adults said they consistently got seven to eight hours of sleep in a 2005 survey by the National Sleep Foundation. Nearly one in six said they got less than six hours a night - a 33 percent increase from the survey's first report in 1998.
One reason: too many distractions.
"There's the Internet, all-night shopping. We're so busy; we have so many responsibilities with our work life, our home life. A lot of people are choosing not to sleep so much," said James Gangwisch, an epidemiologist who researches sleep habits at Columbia University.
Junk food and a lack of exercise are obvious culprits in the nation's obesity epidemic. But would obesity be less of a problem if people addressed their sleep problems before gaining those extra pounds?
"The information we have suggests that might be the case," said Michael Twery, director of the National Center on Sleep Disorders Research, which is part of the National Heart, Lung, and Blood Institute.
The NHLBI has spent $20 million since 2003 on 14 studies exploring ways that sleeping problems contribute to obesity and other health issues/
Dr. Giovanni Cizza, a National Institutes of Health researcher in Bethesda, has enrolled 45 volunteers from the Baltimore-Washington area so far in a study to see whether obese patients with sleep problems will lose more weight than a control group by improving their sleep habits during a year of dieting.
Volunteers have so far extended their shuteye an average of 40 minutes a night by following basic techniques such as minimizing their use of caffeine and alcohol and skipping daytime naps, Cizza said.
