The Importance of Good Quality Sleep

Tuesday, 03 November 2009 14:42 Last Updated on Wednesday, 03 August 2011 12:48 Written by Administrator

The Dream Diet: Losing Weight While You Sleep

Can more sleep really help us control our weight? Three top experts explore the possibilities.
By Colette Bouchez WebMD Weight Loss Clinic-Feature  Reviewed by Leonard J. Sonne, MD

Lose weight while you sleep. It sounds like something you'd hear on a late night infomercial -- just around the time you are reaching for that bag of cookies because, well, you can't sleep. But as wild as the idea sounds, substantial medical evidence suggests some fascinating links between sleep and weight. Researchers say that how much you sleep and quite possibility the quality of your sleep may silently orchestrate a symphony of hormonal activity tied to your appetite.

"One of the more interesting ideas that has been smoldering and is now gaining momentum is the appreciation of the fact that sleep and sleep disruption do remarkable things to the body -- including possibly influencing our weight," says David Rapoport, MD, associate professor and director of the Sleep Medicine Program at the New York University School of Medicine in New York City. While doctors have long known that many hormones are affected by sleep, Rapoport says it wasn't until recently that appetite entered the picture. What brought it into focus, he says, was research on the hormones leptin and ghrelin. First, doctors say that both can influence our appetite. And studies show that production of both may be influenced by how much or how little we sleep. In fact, have you ever experienced a sleepless night followed by a day when no matter what you ate you never felt full or satisfied? If so, then you have experienced the workings of leptin and ghrelin.

How Hormones Affect Your Sleep
Leptin and ghrelin work in a kind of "checks and balances" system to control feelings of hunger and fullness, explains Michael Breus, PhD, a faculty member of the Atlanta School of Sleep Medicine and director of The Sleep Disorders Centers of Southeastern Lung Care in Atlanta. Ghrelin, which is produced in the gastrointestinal tract, stimulates appetite, while leptin, produced in fat cells, sends a signal to the brain when you are full.

So what's the connection to sleep? "When you don't get enough sleep, it drives leptin levels down, which means you don't feel as satisfied after you eat. Lack of sleep also causes ghrelin levels to rise, which means your appetite is stimulated, so you want more food," Breus tells WebMD.
The two combined, he says, can set the stage for overeating, which in turn may lead to weight gain.

Studies: Those Who Sleep Less Often Weigh More
How the hormones leptin and ghrelin set the stage for overeating was recently explored in two studies conducted at the University of Chicago in Illinois and at Stanford University in California.
In the Chicago study, doctors measured levels of leptin and ghrelin in 12 healthy men. They also noted their hunger and appetite levels. Soon after, the men were subjected to two days of sleep deprivation followed by two days of extended sleep. During this time doctors continued to monitor hormone levels, appetite, and activity.

Studies: Those Who Sleep Less Often Weigh More continued...
The end result: When sleep was restricted, leptin levels went down and ghrelin levels went up. Not surprisingly, the men's appetite also increased proportionally. Their desire for high carbohydrate, calorie-dense foods increased by a whopping 45%. It was in the Stanford study, however, that the more provocative meaning of the leptin-ghrelin effect came to light. In this research -- a joint project between Stanford and the University of Wisconsin -- about 1,000 volunteers reported the number of hours they slept each night. Doctors then measured their levels of ghrelin and leptin, as well as charted their weight.
The result: Those who slept less than eight hours a night not only had lower levels of leptin and higher levels of ghrelin, but they also had a higher level of body fat. What's more, that level of body fat seemed to correlate with their sleep patterns. Specifically, those who slept the fewest hours per night weighed the most.

Eating and Sleep Apnea: The New Connection
As a result of these and other studies, researchers began to theorize that getting more sleep just might be the answer to society's burgeoning waistline. But before you trade the cost of your gym membership for a pricey new mattress, take note: Experts also say the relationship is not as obvious as it seems.

The reason: Enter the somewhat mysterious nocturnal ailment known as "obstructive sleep apnea." People with sleep apnea may stop breathing for up to a minute, sometimes hundreds of times during the night while sleeping, says Dominic Roca, MD, director of the Connecticut Center for Sleep Medicine at Stamford Hospital. Though the exact cause of the problem remains unknown, Roca and others believe that in most instances physical abnormalities inside the mouth and neck cause the soft tissue in the rear of the throat to collapse. This briefly closes off air passages many times during a night, causing disruption in breathing and a tendency to snore. The end result: Although you may go to bed early and think you are getting a good night's rest, the disruption in breathing prevents you from getting deep sleep. Eight hours of disrupted shut eye can leave you feeling like you had only four.  "You wake up feeling tired and continue to feel tired all day," Roca tells WebMD.

The Link Between Sleep Apnea and Weight
So what does sleep apnea have to do with weight gain?
First, says Roca, patients who suffer from sleep apnea are more likely to be obese. However, studies show they do not have the usual low leptin levels associated with being overweight. In fact, Roca says that folks with sleep apnea have uncharacteristically high levels of leptin. What's more, when their apnea is treated, leptin levels drop -- and somehow that helps them to lose weight.

"I've had about thirty patients who, when successfully treated for their sleep apnea were able to lose weight -- possibly because they had more energy, so they were more active and they just ate less," says Breus. So why does low leptin seem to cause weight gain in some folks while allowing others to lose weight? One theory says that it may not be the level of this hormone that matters so much as a person's individual response to it. In much the same way that obese people can become resistant to insulin, folks with apnea may be resistant to the fullness signal that leptin sends to the brain. "It's like the body is trying to tell them to stop eating, but their brain just isn't getting the message," says Breus.

Another theory: The overall response to leptin may be more individual than we think. Experts say our environment, dietary habits, exercise patterns, personal stress levels, and particularly our genetics may all influence the production of leptin and ghrelin, as well as our response to them.
The fact that we just don't know causes at least some experts to view all the research on sleep and weight with a cautious or skeptical eye.

"There is a serious challenge to the closing of the loop. That isn't to say that what we know about leptin and ghrelin is not important, or that when we finally do understand it that it won't be crystal clear -- but right now it just isn't," Rapoport tells WebMD.
Breus agrees: "I think we are likely to find that bad sleep matters but that it's likely to be bad sleep plus some other problems. I don't think we know what they are yet."

Sleep: You Can't Lose
Until doctors do know more, most experts agree that if you are dieting, logging in a few extra hours of sleep a week is not a bad idea, particularly if you get six hours of sleep or less a night. You may just discover that you aren't as hungry, or that you have lessened your craving for sugary, calorie-dense foods. "One thing I have seen is that once a person is not as tired, they don't need to rely on sweet foods and high carbohydrate snacks to keep them awake -- and that automatically translates into eating fewer calories," says Breus.

If, on the other hand, you already sleep a lot, or you increase your sleep and feel even more tired, you should talk to your doctor. Experts say you may be one of the thousands of people with undiagnosed sleep apnea. Says Roca: "As research continues, more and more data comes to the forefront to suggest that you simply can't cut back on sleep without paying some price."

You May Have a Sleep Disorder If...

Reviewed By Stuart Meyers, MD  By Michael Breus
WebMD Feature

Wake up to this simple fact: You are not supposed to be sleepy, with your feet draggin' and lids laggin' during the day. Do not let the notion that "I have always been this way" fool you into thinking it's OK. You should awaken feeling relatively refreshed and remain alert throughout the day -- every day.
Have you ever...
•    ...awakened after seven to eight hours of sleep feeling unrefreshed?
•    ...spontaneously fallen asleep during meetings or social events?
•    ...gotten a creepy, crawly sensation in your legs, with an irresistible urge to move them, especially when you lie down in bed at night?
•    ...found that your bed partner has vanished sometime in the night because your snoring was no melodic symphony, or you literally kicked your partner out of bed?
If any of this rings true, you may have a sleep problem, a medical sleep disorder, or a related medical condition for which treatment may literally change your life.

Waking after seven to eight hours of sleep and feeling unrefreshed could be a sign of poor quality sleep. The quality of sleep is as vitally important to our health and well-being as is the quantity. Our sleep has a complex pattern, or architecture, consisting of four stages that run through various cycles during the night. During certain stages and times of the sleep cycle, we secrete a variety of hormones and other substances that help regulate our metabolism and other health-related factors. If our sleep patterns are altered, it may leave us feeling unrefreshed, tired, and sleepy, as well as put us at risk for a host of serious medical conditions.

Let's first briefly distinguish among sleep problems, primary sleep disorders, and sleep disorders secondary to medical conditions.
Sleep problems often occur as the result of poor "sleep hygiene" or "bad habits." These are a range of practices and environmental factors, many of which are under your control. They include things like smoking, drinking alcohol or caffeine, vigorous exercise or eating a large meal before bed, jet lag from travel across time zones, and psychological stressors like deadlines, exams, marital conflict, and job crises that intrude on your ability to fall asleep or stay asleep. Designing and sticking with a good sleep hygiene program should alleviate these types of problems.

There are more than 85 recognized sleep disorders, the most recognizable of which may be insomnia, sleep apnea, narcolepsy, and restless leg syndrome. These and others may manifest themselves in various ways.

Apnea
Your patient and empathic bed partner, with velvet hammer high overhead, notices that you suddenly cease not only your snoring, but your breathing as well. You actually stop breathing, for 10, then 20, then 30 seconds. Then, to his or her surprise and dismay, you begin to gasp for air, as if it were your last breath. This cycle repeats itself over and over, all night long. For your part, you may be totally unaware of all of that, as the alarm clock rings. You may wake with a dry mouth, a headache, and feeling hungover. You may also be sleepy during the day, have significant memory loss, concentration, attention, mood and other related problems. This rather horrifying scenario is typical for a disorder called sleep apnea.
There are two types of sleep apnea, obstructive (OSA) and central (CSA). In OSA the throat collapses during sleep, preventing the flow of air to your lungs. As your oxygen levels decrease, your brain gets an alert message to "wake up and breath." These apnea episodes may occur 20 to 60 to 100 or more times per hour.

CSA is far less common, occurring in less than 10% of cases. Here, the brain fails to send a signal to breath. This can occur in various heart and neurological disorders.

Present in about 7% of the population, the prevalence of sleep apnea is on par with diabetes and asthma. It is also a primary risk factor for high blood pressure. Fortunately, with the proper diagnosis, it can be treated quite effectively.
There are three categories of treatment for obstructive sleep apnea:
1.    Physical or mechanical therapy
2.    Surgery
3.    Non-specific therapy
Which therapy is used depends on your specific medical, lab, and physical exams and other findings.  Physical or mechanical therapies only work at the time they are properly used. Apnea episodes return when they are not utilized.

•    Continuous positive airway pressure (CPAP) is the most common treatment. With the use of a snugly fitted face mask or nasal plug, air is blown into the nasal passages, forcing the airway open and allowing air to flow freely. The pressure is continuous and constant and is adjusted so that it is just enough to open the airway.
•    Dental or oral appliances reposition the lower jaw and tongue, moving them outward, creating something akin to a pronounced "underbite." Used in mild to moderate sleep apnea, this physically opens the airway, allowing the free flow of air. They are custom-made devices usually fitted by a dentist or orthodontist.
Surgery opens the airway by removal of tissues, like tonsils, adenoids, nasal polyps, and structural deformities that may obstruct it. There are several types of procedures, but none are completely successful and without risk. It is also difficult to predict the outcome and side effects.
•    One procedure, called uvulopalatopharyngoplasty, removes tissue at the back of the throat. In addition to having low success rates of between 30%-60%, it is difficult to predict exactly which patients will benefit, as well as the long-term outcome and side effects.
•    Other procedures include tracheostomy (creating a hole directly in the windpipe, for those with severe obstruction),surgical reconstructionfor those with deformities, andprocedures to treatobesity, which contributes to apnea.
Non-specific therapy addresses the behavioral aspects that may be an important part of a treatment program.
•    If you are overweight, weight loss can reduce the number of apnea episodes. One should avoid depressants, like alcohol and sleeping pills, which can increase the likelihood of and prolong apnea episodes. Some people have apnea events only when lying on their back. So placing a pillow or other device to help keep you on your side may also help.
Restless Leg Syndrome (RLS)

Particularly around bedtime, many people (about 15% of the population) experience "pins and needles feelings," an "internal itch," or a "creeping, crawling sensation" in their legs, with a subsequent irresistible urge to relieve this discomfort by vigorously moving their legs. This movement totally relieves the discomfort. These symptoms are classic for restless leg syndrome.RLS makes if difficult to fall asleep and may also awaken you out of sleep, forcing you to walk around to relieve the discomfort. Though not considered medically serious, symptoms of RLS can range from bothersome to having a severe impact on you and your bed partner's lives.

Most people with RLS also have periodic limb movement disorder (PLMD), repetitive movements of the toe, foot, and sometimes knee and hip during sleep. They are often recognized as brief muscle twitches, jerking movements, or an upward flexing of the feet. As with sleep apnea, sufferers may be unaware that RLS and PLMD disturb sleep and produce symptoms similar to those noted above. Once again, it is often the bed partner that brings this to light, as movements awaken him or her throughout the night. It is important to note that RLS and PLMD are associated with several other medical conditions, including iron-deficiency anemia. So one should, as always, seek proper medical attention.

RLS generally responds well to medication, but since it may occur sporadically with spontaneous remissions, the continuous use of medications is generally recommended for symptoms occurring at least three nights per week. Sleep experts use three types or classes of medications for RLS and PLMD:
1.    Dopaminergic agents: This class enhances a brain chemical known as dopamine. Mirapex and Permax have become first-line medication, over older drugs like L-Dopa with Sinemet.
2.    Benzodiazepines are generally sleep experts' second-line medication. They must be used carefully due to the potential for addiction and the negative impact on sleep. This class includes such drugs as diazepam (Valium, Diastat), Klonopin, Restoril, and Halcion.
3.    Opioids represent the third-line of preferred medication generally and is reserved for those with more severe symptoms. They may be used alone or in conjunction with other medications. This class includes codeine (active ingredient in Tylenol #3), oxycodone (active ingredient in Percocet), Darvon, and methadone (in very severe cases only).
As one would expect, all of these medications are available by prescription only and should be taken only while under a doctor's care.

Narcolepsy
Falling asleep spontaneously may indicate the syndrome of narcolepsy. Excessive daytime sleepiness is typically the first symptom. It's the overwhelming need to sleep when you prefer to be awake. Narcolepsy is associated with cataplexy, a sudden weakness or paralysis often initiated by laughter or other intense feelings, sleep paralysis, an often frightening situation, where one is half awake yet cannot move, and hypnagogic hallucinations, intensely vivid and scary dreams occurring at the onset or end of sleep. One may also experience automatic behavior, in which one performs routine or boring tasks without full memory later.
There are both behavioral treatments and medications for this situation, which can make life livable again.
General behavioral measures include:
•    Avoiding shift work
•    Avoiding heavy meals and alcohol intake
•    Regular timing of nighttime sleep
•    Strategically timed naps
Medications typically involve stimulants in attempt to increase the level of alertness and antidepressants to control the associated conditions noted above. The effects of stimulant medications vary widely and their dosing and timing must be individualized.
•    Provigil is a relatively new medication that improves alertness but does not act as a stimulant for other body systems. It has few side effects and low abuse potential.
•    Stimulants include dextroamphetamine sulfate (Dexedrine, Dextrostat), methylphenidate hydrochloride (Ritalin, Concerta, others), and Cylert.
•    Antidepressants include:
o    Multicyclics like Tofranil, Norpramin, Anafranil, and Vivactil.
o    Selective serotonin re-uptake inhibitors (SSRIs). These include Prozac, Paxil, and Zoloft.
Seeing a sleep specialist is essential for proper diagnosis and treatment.
Many sleep disorders are secondary to a variety of medical and mental-health disorders, pain, and even the treatments for these disorders. Medical conditions like diabetes, congestive heart failure, emphysema, stroke, and others may have nighttime symptoms that disturb sleep. Depressive illnesses and anxiety disorders are associated with sleep disturbances, as is the pain from conditions like arthritis, cancer, and acid reflux, to name a few.

Recognizing and distinguishing among sleep problems, primary sleep disorders, and those secondary to or associated with medical conditions is critical to proper diagnosis and treatment. It is equally important, however, to realize that they often interact in a complex manner, with each impacting the other. For example, poor sleep can affect your mood, and your mood can affect the quality of your sleep. Poor sleep can contribute to obesity, and obesity can cause sleep disorders. Exactly how all these factors interact is not completely known, but we can target each aspect individually and achieve vastly improved interventions and treatments.

The magnitude of the impact of sleep disorders on our individual and public health, safety, and performance is truly enormous. Fortunately, increasing awareness is leading to more effective treatment, less suffering, and happier, more productive lives.
Originally published April 1, 2003.
Medically updated September 2004.
Not Enough Sleep All Too Common

Few Adults Are Always Well-Rested, and Americans Get Less Sleep Than 20 Years Ago, Says CDC

By Miranda Hitti WebMD Medical News  Reviewed by Louise Chang, MD

Feb. 28, 2008 -- U.S. adults are sleeping less than they did two decades ago, leaving few people feeling well-rested all the time, new CDC data show. The CDC today issued two new reports that peek into the sleep habits of U.S. adults. The first report comes from 19,589 adults in four states -- Delaware, Hawaii, New York, and Rhode Island -- who took part in 2006 telephone survey. They were asked how often, during the previous 30 days, they felt they had gotten enough rest or sleep. Here are the results:
•    10% said they didn't get enough sleep or rest in any of the previous 30 days.
•    About 30% said they got enough sleep or rest every day during the previous 30 days.

Adults aged 55 and younger and people who say they were unable to work were particularly likely to report not getting enough sleep. Participants weren't asked how much sleep or rest they got -- just whether they felt that they got "enough" rest or sleep. The findings might not apply to the rest of the country.

Sleep Shortfall
More Americans are skimping on sleep than in the past, according to the CDC's second set of sleep statistics. In a then-and-now comparison, the CDC charted the percentage of U.S. adults in 1985 and 2006 who report getting no more than six hours of sleep during a typical 24-hour period.

The bottom line: Getting up to six hours of sleep was more common in 2006 than in 1985. That pattern held for all age groups and was strongest for people aged 30-64.  Both studies appear in the Feb. 29 edition of the CDC's Morbidity and Mortality Weekly Report. The studies don't show why people are sleeping less. It could be because of sleep disorders, other conditions, or lifestyle factors, including staying up late to surf the Internet or watch TV.

Sleep Tips
The CDC notes that, according to the National Sleep Foundation, most adults need seven to nine hours of nightly sleep to feel fully rested, and kids need more sleep. An estimated 50-70 million people in the U.S. have chronic sleep and wakefulness disorders, according to background information in the CDC's report.
If you're one of the many people who are short on sleep, here are the CDC's tips:
•    Stick to a regular sleep schedule.
•    Sleep in a dark, well-ventilated space at a comfortable temperature.
•    Avoid stimulating activities within two hours of bedtime.
•    Avoid caffeine, nicotine, and alcohol in the evening.
•    Avoid going to bed on a full or empty stomach.
•    See a doctor if you are concerned about chronic sleep problems.

SOURCES:
CDC, Morbidity and Mortality Weekly Report, Feb. 29, 2008; vol 57: pp 200-203, 209.
News release, CDC.
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