William Penn Life, 2007 (42. évfolyam, 1-12. szám)
2007-07-01 / 7. szám
___________________[HealthPage___________________ The need for sleep Wake up to the risks of shortened slumber from News In Health DO YOU TOSS AND TURN at night, or have problems falling asleep or staying asleep? Do you have trouble staying awake and alert during the day? If so, you may be one of the estimated 50 to 70 million Americans who have a sleep disorder. Experts estimate that about one-third of adult Americans will experience some sort of sleep disorder in their life time. And, while many sleep disorders can be treated, most of them go undiagnosed. Why we sleep remains something of a mystery. Dr. Michael Twery, director of the National Center on Sleep Disorders Research at the National Heart, Lung and Blood Institute, says, "sleep originates with the timing of our biological clock. The biological clock operates in almost all of our tissues." A particular region of the brain called the suprachiasmatic nucleus, he says, operates as the master biological clock. It orchestrates what Twery calls a "symphony" of hormones and other changes that prepare our body for sleep. It's clear that our body needs this sleep, because of what happens when we don't get enough of it. "Too little sleep or not enough restorative sleep can seriously affect the way we think, behave, form memories and perform at work and school," explains Dr. Merrill Mitler, program director for sleep research at the National Institute of Neurological Disorders and Stroke. "A continued lack of sleep also puts us at risk for mood disorders such as depression and can lead to poor concentration and poor judgment, social problems, greater risk of car crashes and increased risk of substance abuse." There is also what Twery calls the "unseen side" of inadequate sleep. Because the timing of sleep is linked to a symphony of chemical reactions throughout the body, Twery explains, it's also linked to our health in more subtle ways. "When these chemical reactions become misaligned," he says, "they can contribute to problems with our metabolism and our cardiovascular system, and can eventually lead to increased risk of disease." Twery recounts one set of experiments in which otherwise healthy young adults developed resistance to insulin after a few nights of only four hours of sleep. Insulin is a hormone needed to convert sugar, starches and Health Links For the latest information about sleep and sleep disorders, log onto the health information page of the National Institutes of Health’s website at: 3 http://health.nih.gov Under “Health Topics A-Z,” click on “S,” then click on “Sleep Disorders.” other food into energy. When the body can't use insulin properly, diabetes can develop. After the researchers allowed the young adults to go back to eight-hour sleep periods, the problem reversed within days. Other studies have found that people who get less sleep tend to have higher rates of obesity, heart disease, high blood pressure and diabetes. A great deal of research is now focused on understanding the underlying links between sleep and these health factors. How much sleep do we need? Adults usually need at least seven to eight hours of sleep a night to feel fully rested when they are awake. School-aged children and teens need at least nine hours. Children in preschool need between 10 and 12 hours a day, and newborns need 16 to 18 hours. Many people unfortunately consider sleep a low priority and try to stay awake as much as they can to do more work, watch some TV or fit other things into their busy days. But others can't sleep because of an underlying problem. In fact, there are more than 70 different types of sleep disorders. Diagnosing a particular sleep disorder can be difficult, but Mitler says that new tools are giving scientists a better understanding of sleep and sleep-deprived states. One key tool is functional imaging, which provides real-time images of brain activity during sleep and the sleepwake stages to learn which areas of the brain may be involved in sleep disorders. Researchers at the National Institutes of Health continue to explore the causes and consequences of sleep problems, such as insomnia, chronic sleep deprivation and obstructive sleep apnea. Even if all these disorders aren't fully under-6 William Penn Life,July 2007
