According to a large survey, less than 1 In 10 Americans sleep in the nude. This is a sad finding considering the fantastic (and scientifically proven!) benefits we gain from ditching PJ's and slipping into our birthday suit. Check out these surprising health benefits ranging from improved hormonal balance and mood to less belly fat, more sex and beyond.
Boost your anti-aging hormones: Plenty of people like to feel cozy at bedtime, but a sleep environment that's too warm can prevent the natural cooling that should take place in your body while you sleep.
Keeping your body or your bedroom too warm (higher than 70˚F (21˚C) will disrupt the release of your main anti-aging hormones, melatonin and growth hormone. When we sleep in total darkness, melatonin is released, triggering a very slight but critical cool-down in the body. As body temperature drops, growth hormone is released and works its regenerative magic.
In fact, sleep itself has been touted as a magic pill precisely because it encourages the release of this youthful hormone. In a study published in the journal "Sleep", researchers showed that you can get safe, legal doses of growth hormone -- and even improve athletic performance -- just by hitting the sack for a deep, restorative sleep.
Its also good for your health in other ways -- researchers have found that people with normal or high blood pressure experience a 20 to 30 per cent reduction in blood pressure and 10 to 20 per cent reduction in heart rate during sleep.
Better body composition: As mentioned, wearing heavy blankets or clothing to bed will impede the release of growth hormone, which means you won't burn fat while you sleep or benefit from night-time repair of your bones, skin and muscles.
Growth hormone (HGH) affects just about every cell in the body. It's essential for tissue repair, muscle building, bone density and healthy body composition. People who sleep less than six hours a night may be three times more likely to develop a condition which leads to diabetes and heart disease (and in turn, weight gain), according to researchers at the University of Warwick. When your sleep is insufficient, your cortisol and hunger hormones both surge, causing a corresponding increase in insulin. You also experience decreases in the fat-burning and appetite-controlling hormones.
Sleep deeper and longer: Research has shown that certain forms of insomnia associated with faulty body temperature regulation and the inability to cool down at night enough to spark a deeper stage of sleep.
In one Dutch study, scientists placed thermosuits on participants to lower skin temperature less than one degree Celsius without affecting core body temperature. The result? People didn't wake up as much during the night and the percentage of the sleep spent in stages 3 and 4 (deep sleep) increased.
In elderly subjects a 0.4 C decrease in skin temperature caused a decline in the probability of early morning waking from 0.58 to 0.04. And believe it or not, you don't sweat or shiver during REM sleep so have no fear that ditching the layers will have you dreaming of icicles.
Lower cortisol and belly fat: As you cool down at night and growth hormone increases, cortisol will also decrease with healthy sleep patterns. Between the hours of 10 p.m. and 2 a.m. is the time when your body is truly resting and recuperating (and cortisol should be at it's lowest). By 2 a.m., your adrenal glands (stress glands) begin to work to produce cortisol, in preparation for the next day, which also peaks at 4 a.m. and then should naturally reach its highest point around 6 a.m. -- just at the right time to get you up out of bed feeling energized.
On the nights that you do not sleep enough, you will wake with a level of cortisol that is abnormally high. This is known to trigger your appetite -- especially for comfort foods (muffins, cookies, etc.) and your tendency to overeat, increase tension/anxiety and fuel belly fat -- even in people who are otherwise thin.
High cortisol levels weaken the body's immune system, raise blood pressure and cholesterol, increase appetite, disrupt our normal sleep patterns, lower your libido, and increases cravings for sugar and carbs. It will also contribute to other hormonal imbalances and health conditions including PMS, infertility, thyroid disease and abnormal blood sugars.
Ode to oxytocin: If you and your partner both sleep in the nude, you can be reaping the benefits of this feel-good hormone. Skin to skin touching (with intimacy, a massage, intercourse, or cuddling) is all that is required. Also involved in sexual responsiveness and orgasm, the hormone oxytocin counteracts stress and depression by combating the harmful effects of cortisol and reduces blood pressure. It has also been shown to improve gut motility and decrease intestinal inflammation. Another bonus? More .. ahem ... opportunities. Let's face it, there's nothing that turns your partner off faster than head-to-toe flannel pajamas. And orgasms are nature's best sleep aid.
Fact: What works for you might not work for your neighbor. "A person's sleep need is genetically pre-determined," says Michael Decker, Ph.D., associated professor at Georgia State University and spokesperson for the American Academy of Sleep Medicine. "Some people need a little bit more, and some need a little bit less." So how do you know how much you need? One tell-tale sign you're not getting enough is falling asleep as soon as you get into bed, says Robert Oexman, D.C., director of the Sleep to Live Institute. "It's very common that people tell me, 'I'm a great sleeper, I fall asleep as soon as my head hits the pillow,'" he says. "That's a sign that you're probably not getting enough sleep." Drifting off should take around 15 minutes if you're regularly fulfilling your sleep needs, he says. And if you wake up feeling refreshed and energetic? You're doing something right, says Decker. However, the people who say they're fine with just six hours of sleep a night are likely setting themselves up for future problems. Research suggests that consistently sleeping fewer than six hours a night can increase stroke and diabetes risk, damage bones and hurt the heart, among other scary side effects.
Fact: There is such a thing as too much sleep, believe it or not. Just like people who regularly sleep fewer than six hours a night, people who consistently clock more than nine or 10 hours a night also face a number of health problems, says Michael A. Grandner, Ph.D., an instructor of psychiatry and a member of the Behavioral Sleep Medicine program at the University of Pennsylvania. We don't quite know yet if too much sleep is the proverbial chicken or the egg, he says, but we do know there is such a thing as too much of a good thing.
Fact: If you're grouchy and crabby from skimping on sleep all week, and then sleep a couple extra hours Saturday morning, you'll find the short-term effects of sleep deprivation vanish pretty quickly, says Grandner. But the long-term impact is still likely dangerous. "The problem [with counting on catching up on sleep] is thinking there's not a consequence of not getting enough sleep all week," says Oexman. "There are consequences of even one night of not getting enough sleep." Plus, if you sleep in too late on the weekends, you're setting yourself up for trouble falling asleep Sunday night. Then, when the alarm goes off Monday morning, you'll find yourself starting the cycle all over again, says Oexman.
Fact: Turns out, lying there staring at the clock hoping sleep will come is one of the worst things you can do, the experts say. "Lying in bed and ruminating about why we're not sleeping can increase anxiety and make it harder to fall asleep," says Decker. If you stew there long enough, you may teach your brain to associate lying in bed with being awake, says Oexman. Instead, get out of bed and do something else for a while to help you wind down. The change of environment can help you avoid a stressful association with your bedroom, as long as it's nothing too exciting and away from any bright light. Half an hour later, try getting back into bed, says Grandner.
Fact: "There's a difference between relaxation and distraction," says Grandner. When you relax, your breathing and heart rate slow down, your muscles release, your thoughts grow calmer -- and none of that happens when you're watching TV. "TV at night is not there to help you sleep, it is there to sell you stuff," he says. Not to mention that the blue light emitted from the TV tricks your brain into thinking it's time to be awake and alert. Experts agree that you should power down all electronic devices at least an hour before bed. Reading a book (that isn't too exciting) can help you relax, but sleep docs are quick to point it has to be the real thing. iPads and other backlit electronic readers emit the same kind of stimulating light as your TV.
Fact: While certainly a nuisance to your bedmate, snoring can be more dangerous to your health than you might know. The vibrations of the soft tissue of your airways that leads to that log-sawing sound can cause swelling overtime. As the swelling further narrows your airways, it becomes increasingly difficult for enough oxygen to pass through, says Oexman. When it's not getting enough oxygen, the brain will trigger snorers to wake up, says Grandner. Most people who snore or have sleep apnea almost immediately fall back to sleep, but some experts hypothesize that the constantly cycling between alert and asleep causes a great deal of stress in the body, particularly to the heart, says Grandner. This could explain why both snoring and sleep apnea have been linked to increased heart risks.
Fact: It might help you doze off, but it becomes seriously detrimental to the quality of your shut-eye later on in the night. It's a much more complicated relationship than just "alcohol makes you pass out," says Grandner. As your body processes the alcohol, it can begin to act as a stimulant, leading to more shallow and less restful sleep later in the night. Drinkers may also be more likely to wake up in the middle of the night and have trouble falling back to sleep. "Alcohol is very disruptive to sleep continuity and leads to fragmented sleep and poor sleep quality," says Decker. "Drink now, pay later."
Fact: Caffeine has a surprisingly-long half life, meaning there's still about half of the original amount of caffeine you ingested in your blood about 12 hours later, says Oexman. Caffeine isn't always the most obvious of sleep-stealers, however. "In most cases when it comes time to sleep, you just don't quite feel ready for it," says Grandner. "You're not feeling the caffeine jitters, you're just less able to wind down, even if you don't realize that it could be a culprit." Even lunchtime caffeine could cause trouble if you're particularly sensitive to caffeine, but definitely steer clear of any after-dinner coffee or tea.
Fact: Even though we totally understand the urge to cuddle up under loads of blankets, a cooler environment is more conducive to good sleep. Because there are specific changes in core body temperature as we prepare for sleep, anything that raises your internal temp can make sleep more difficult, says Grandner. Some people would rather save on electricity and turn the AC off at night, but if you find yourself struggling to sleep as the weather warms up, try keeping a fan running at least, he suggests. In most cases, says Oexman, having your head exposed to some cool air will counteract the effects of too many blankets, but for bedmates with opposite temperature needs, he suggests sleeping with two sets of sheets and blankets, even if you're in the same bed.
Fact: When timed right, it shouldn't! In fact, there's substantial research that shows nappers have improved memory, alertness and performance after a short siesta. Make sure you're not napping too close to bedtime, and cut it to 30 minutes or less, otherwise you risk drifting into deeper sleep and feeling groggier when you wake up. A word of caution for people who have difficulty sleeping: If you already find it hard to fall asleep, wake up multiple times throughout the night or wake up too early, it's probably wise to skip the nap, says Oexman.
Fact: Not necessarily. This thinking probably stems from studies of people doing much more intense exercise much closer to bedtime than most of us really do, says Grandner. If you have no other time than at night to hit the gym, don't skip the workout, just make sure it isn't too rigorous and that you allow yourself ample time to cool off before jumping into bed, says Grandner. However, if you already have trouble falling asleep at night, the boost to our core body temperature caused by exercise could add fuel to the fire, says Oexman. People with trouble sleeping should look to exercise at least three to four hours before bedtime, he says.
Fact: Your furry friends are not the best bed partners. "Some people feel that having their pet in the room helps them sleep better," says Decker, "but if Fido snores and Fluffy is roaming around on the bed as cats often do, it can be very disruptive!"
Follow Natasha Turner, ND on Twitter: www.twitter.com/drnatasha