May 8, 2008
Too Much, Too Little Sleep Brings Bad Health
New research shows that people that get fewer than 6 hours of sleep a night or more than nine are the most likely to be obese. The government study is one of the largest to show a link between irregular sleep and big stomachs.
The research also linked light sleepers to higher smoking rates, less physical activity and more alcohol use.
Dr. Ron Kramer, a Colorado physician and a spokesman for the American Academy of Sleep Medicine, said the research adds weight to a stream of studies that have found obesity and other health problems in those who don't get proper shuteye.
Kramer said the data shows that short sleepers and long sleepers don't do so well.
The National Center for Health Statistics, part of the Centers for Disease Control and Prevention, released the study that was based on door-to-door surveys of 87,000 U.S. adults from 2004 through 2006.
The studies lead author, Charlotte Schoenborn, said that surveys like this don't prove cause-effect relationships, so it's not clear whether smoking causes sleeplessness or if lack of sleep prompts smoking.
Other influences such as depression"”which can contribute to heavy eating, smoking, sleeplessness and other problems"”were not accounted for in the study.
Thirty-one percent of those surveyed were current smokers"”smoking was highest for those getting under six hours of sleep. Those getting over nine hours a night were also heavy smokers at 26 percent.
The smoking rate in the U.S. is around 21 percent. The rate was lower for those in the study who sleep seven to eight hours, at 18 percent.
Similar results were shown for obesity. About 33 percent of those who slept less than six hours were obese, and 26 percent for those who got nine or more. Normal sleepers only showed 22 percent obesity.
Those who consume large amounts of alcohol appear to be getting less sleep. However, alcohol use for those who slept seven to eight hours and those who slept nine hours or more was similar.
Almost half of people who slept nine hours or more each night were physically inactive in their leisure time, which was worse even than the lightest sleepers and the proper sleepers. Many people who sleep nine hours or more may have serious health problems that make exercise difficult.
The elderly were among those groups that get the least amount of sleep, explaining why physical activity rates are low. But experts said younger people who skimp on sleep might just be too tired to exercise.
Experts also believe that stress and other psychological problems can also explain why some sleep less than others.
James Gangwisch, a respected Columbia University sleep researcher, noted that other studies have found inadequate sleep is tied to appetite-influencing hormone imbalances and a higher incidence of diabetes and high blood pressure.
Gangwisch was not involved in the study but said that health experts may start recommending getting enough sleep as a standard approach to weight loss and the prevention of obesity.
On the Net:
National Center for Health Statistics
American Academy of Sleep Medicine