Contributed by Jai A. Dennison| 11 January, 2005  03:18 GMT
Loss of sleep alters the complex metabolic pathways that control appetite, food intake and energy expenditure, say two Northwestern University researchers in an editorial published in the January 10 issue of the
Archives of Internal Medicine. The upshot? A growing number of U.S. citizens are fat and tired.The authors, Joseph Bass, M.D., assistant professor of medicine, and Fred W. Turek, Charles E. and Emma H. Morrison Professor of Biology and director of Northwestern's Center for Sleep and Circadian Biology, base their comments on two obesity studies also published this week in the journal.
Forbears Snoozed More
One study, conducted by Robert D. Vorona, M.D., from Eastern Virginia Medical School, Norfolk, and colleagues, found that insufficient sleep causes neurocognitive changes -- such as excessive daytime sleepiness, altered mood, and increased risk for work-related injury and automotive accidents -- according to background information in the article.
Americans today get less sleep than they did a century ago, on average. With declining sleep times, there also has been an increase in the number of both obese and severely obese people in the U.S.
New Obesity Villain
"In recent years, a new and unexpected 'obesity villain' has emerged, first from laboratory studies and now, as reported by Vorona et al in this issue of the Archives, in population-based studies: insufficient sleep," say Bass, Turek, Morrison and Morrison.
"However, while there is a growing awareness among some sleep, metabolic, cardiovascular and diabetes researchers that insufficient sleep could be leading to a cascade of disorders," they note, "few in the general medicine profession or in the lay public have yet made the connection."
Twenty Extra Minutes
As younger and older Americans alike struggle with an inability to get enough sleep and to control weight, the authors stress the need to investigate whether intervention in sleep disorders could help reduce obesity's negative effects on metabolism and health.
"Americans experience insufficient sleep and corpulent bodies," write Vorona et al. "Clinicians are aware of the burden of obesity on patients. Our findings suggest that major extensions of sleep time may not be necessary, as an extra 20 minutes of sleep per night seems to be associated with a lower BMI.
Metabolic Syndrome
Even school-age American children are not obtaining enough sleep, Bass and Turek note in commenting on a second article appearing in the same issue of the Archives. Sleep loss during the formative years of life could be putting our youth on a trajectory toward obesity and the metabolic syndrome, they warn.
Obesity is associated with metabolic and cardiovascular disorders often referred to as the metabolic syndrome, which increases an individual's risk of developing a serious disease, say Bass and Turek.
In addition to excess body weight, factors include high blood pressure, high insulin levels and one or more abnormal cholesterol levels. As many as one in four American adults and 40 percent of adults age 40 or older have metabolic syndrome -- an increase of 61 percent over the last decade, according to the Mayo Clinic. |
|