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A Third of Americans Don't Sleep 7 Hours

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This is an older article that may not reflect Dr. Mercola’s current view on this topic. Use our search engine to find Dr. Mercola’s latest position on any health topic.

sleep deprivationInsufficient sleep not only can affect your memory and daily performance, but studies have now shown that lack of sleep can impair your ability to drive an automobile.

The U.S. Department of Transportation reports that drowsiness, including nodding off while driving, is responsible for 1,550 deaths and 40,000 injuries each year.

When the Center for Disease Control and Prevention surveyed 75,000 drivers in 12 states, results declared that 35 percent slept less than seven hours in a night, 48 percent snored, and nearly 38 percent had fallen asleep at least once during the day, while nearly 5 percent admitted to falling asleep behind the wheel.

Results also proved drivers ages 25 to 35 are more prone to nodding off while driving and men are more prone to falling asleep while driving than women. According to ABC News, Dr. Allan Pack, director of the Center for Sleep at University of Pennsylvania reports:

"Most of us believe that there are a lot more fall asleep crashes than reported… [I]t's probably not reported accurately because a number of states don't even having a 'falling asleep while driving' tick in the box when reporting a car crash… [P]eople believe that if they cut back on their sleep there is no real consequence. Everyone knows the dangers of alcohol, but I don't think people understand the dangers of drowsy driving."

In related news, USA Today reports that people who are sleep-deprived eat close to 300 calories a day more than they do when they are well-rested. Ice cream is one of the most common foods people eat when tired.

So perhaps it's not surprising an additional study also showed that you can double your chances of reaching your target weight if you get the proper amount of sleep each night -- between six and eight hours. According to the Telegraph, the study found that people trying to lose at least 10 pounds were more likely to reach their goal if they had lower stress levels and got the right amount of sleep.
 
Dr. Mercola's Comments:

Data from the U.S. Centers for Disease Control and Prevention (CDC) found that over 35 percent of Americans reported getting less than seven hours of sleep on average during a 24-hour period. There is some controversy over what the ideal amount of sleep actually is, but research seems to be accumulating that sleeping less than eight hours a night has significant cumulative consequences.

Case in point, the CDC analysis found that people who slept fewer than seven hours were more likely to report unintentionally falling asleep during the day -- including nodding off or falling asleep while driving. This is easily one of the most significant and potentially deadly risks of too little sleep, as the National Highway Traffic Safety Administration estimates that drowsy driving results in 1,550 deaths, 71,000 injuries and more than 100,000 accidents each year. But there are other, more insidious, risks to too little sleep as well, and chief among them is the impact on your weight.

Lack of Sleep Could be Making You Fat

Two recent studies added to the evidence showing that your sleeping habits influence both your ability to lose weight and your tendency to eat more:

  • People trying to lose weight were more likely to lose 10 pounds when they slept between six and eight hours a night, according to research in the International Journal of Obesity.
  • People ate an average of nearly 300 calories more when they were sleep-deprived compared to when they were well rested, research presented at an American Heart Association revealed. And the calories overwhelmingly came from junk foods like ice cream and fast food.

Other research found that among adults younger than 40, those who typically slept for five hours or less each night had a greater accumulation of belly fat, and yet another study, published in the Annals of Internal Medicine, found dieters who slept for 8.5 hours lost 55 percent more body fat than dieters who only got 5.5 hours of shut-eye.

This is only scratching the surface of the research linking your sleeping habits with your body weight -- so what's this connection all about?  It is likely the effect of altered metabolism, because when you're sleep deprived, leptin (the hormone that signals satiety) falls, while ghrelin (which signals hunger) rises. In one study, researchers found that people who received only four hours of sleep a night for two nights experienced:

  • 18 percent reduction in leptin
  • 28 percent increase in ghrelin

This combination leads to an increase in appetite. Additionally, sleep-deprived people tend to eat more sweet and starchy foods, as opposed to vegetables and proteins. For instance, in the study mentioned above where people ate 300 extra calories when they were sleep-deprived.

The lead researcher told USA Today:

"Ice cream stood out as the preferred food during the sleep-deprived state."

These sugar cravings may stem from the fact that your brain is fueled by glucose (blood sugar); therefore, when lack of sleep occurs, your brain starts searching for carbohydrates to keep going. If you're chronically sleep deprived, consistently giving in to these sugar cravings will virtually guarantee you'll gain weight.

More Consequences of Too Little Shut-Eye

I would easily rank a sound night's sleep as high as proper diet and exercise in terms of its influence on optimal health. One of the explanations for why the health effects of sleep deprivation and sleep disruption are so numerous is that the circadian system "drives" the rhythms of biological activity at the cellular level. Hence disruptions tend to cascade outward throughout your entire body.

Among some of the consequences of too little sleep are:

And according to a report in the Journal of the American Medical Association (JAMA), lack of sleep can further exacerbate other serious and chronic diseases, such as:

Parkinson disease (PD) Alzheimer disease (AD) Multiple sclerosis (MS)
Gastrointestinal tract disorders Kidney disease Behavioral problems in children

According to another study, people with chronic insomnia also have a three times greater risk of dying from any cause.  Sleep deprivation can even cause changes in your brain activity similar to those experienced by people with psychiatric disorders, and your body does most of its repairs during sleep, so not getting enough of it can impair your immune system, leaving you less able to fight off diseases of ALL kinds.

How do You Know You're Getting Enough Sleep?

Obviously if you feel well-rested and are able to wake up in the morning with no problem, you're probably doing just fine in the sleep department. But if you're fatigued, nodding off or yawning throughout the day, and just want to go back to bed when your alarm clock goes off in the morning, your sleep schedule may need some tweaking.

Generally speaking, adults need between six and eight hours of sleep every night. However, there are plenty of exceptions. Some people feel fine on as little as five hours a night, while others need as much as nine or 10 in order to feel at their best.

The amount of sleep you need can also drastically change depending on circumstances. For example, most people need more sleep when feeling ill, or during emotionally stressful times. Pregnant women also typically need more sleep than usual during the first trimester.

So my advice is to carefully and sensitively listen to your body and respond accordingly. And don't think you're going to meet all of your sleep needs by sleeping in for one morning on the weekend.  Chronic lack of sleep has a cumulative effect when it comes to disrupting your health. You cannot skimp on sleep on weekdays, thinking you'll "catch up" over the weekend. What's needed is consistency, and when it comes to sleep, routine is the word.

Creating a Healthy Sleep Routine

If you're a parent, you probably automatically adopted such a routine for your kids -- perhaps winding down with quiet activities for an hour or two before bedtime, then getting into pajamas and reading a book.

Why are bedtime routines so important for kids?

Because they work -- and they can work for you too. So if you're staying up late watching TV, surfing the Web or working, it's time to set some limits. Determine a set bedtime for yourself, just as you do for your children, and avoid watching TV or using electronics for about an hour prior to going to bed. It is too stimulating to your brain, making it more difficult to "shut down" and fall asleep.

Instead, try spending this wind-down time doing something that soothes and relaxes your mind. You may want to spend time journaling, meditating, sipping herbal tea, washing your face, or reading a calming or spiritual book.

I also recommend getting to bed as early as possible. Your bodily systems, particularly your adrenals, do a majority of their recharging or recovering during the hours of 11 p.m. and 1 a.m., so you should definitely try to be asleep during those hours. From there, make sure your bedroom is ideally suited for sleep, as this can also go a long way to ensure restful and uninterrupted sleep:

  • Cover your windows with blackout shades or drapes to ensure complete darkness. Even the tiniest bit of light in the room can disrupt your internal clock and your pineal gland's production of melatonin and serotonin. Even the faint glow from your clock radio could be interfering with your sleep.

    Also close your bedroom door, get rid of night-lights, and refrain from turning on any light during the night, even when getting up to go to the bathroom. If you have to use a light, install "low blue" light bulbs in your bedroom and bathroom. These emit an amber light that will not suppress melatonin production.
  • Keep the temperature in your bedroom at or below 70 degrees F (21 degrees Celcius). Many people keep their homes and particularly their upstairs bedrooms too warm. Studies show that the optimal room temperature for sleep is quite cool, between 60 to 68 degrees F (15.5 to 20 C). Keeping your room cooler or hotter can lead to restless sleep.

    When you sleep, your body's internal temperature drops to its lowest level, generally about four hours after you fall asleep. Scientists believe a cooler bedroom may therefore be most conducive to sleep, since it mimics your body's natural temperature drop.

You can find my comprehensive recommendations and guidelines to help improve your sleep in my article 33 Secrets to a Good Night's Sleep. If you're having trouble sleeping, this is the place to look to get your sleep back on track.

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