According to the Centers for Disease Control and Prevention, more than a third of Americans sleep fewer than seven hours nightly. So why do so many people believe they can fully function with only five or six hours of sleep? We're here to debunk what many consider conventional wisdom surrounding sleep.
A survey conducted by sleep experts analyzed 20 of the biggest myths linked to sleep. Studies confirm that sleep deprivation, defined as fewer than seven hours a night, is associated with a risk of developing obesity, high blood pressure, diabetes, heart disease, stroke, mental disease and even early death.
Here are some of the top myths debunked:
"Being able to fall asleep 'anytime, anywhere' is a sign of a healthy sleep system." This is false, and, in fact, it's alarming because it suggests signs and symptoms of obstructive sleep apnea, or OSA. If you find yourself falling asleep periodically throughout the day, snoring at night or waking up gasping for air during sleep, then you may be at risk for OSA, which has long-term health consequences including the development of heart failure and high blood pressure.
"It's better to have a warmer bedroom than a cooler bedroom." Get your blankets out and crank up your AC because this statement is false. Studies report that a "hot and stuffy" bedroom is associated with poor sleep. The optimal recommended temperature for ideal sleep in the bedroom is between 65 and 70 degrees F.
"Exercising within four hours of bedtime will disturb your sleep." This is false, according to a survey by sleep-medicine experts who found exercise and sleep appear to be mutually beneficial. A large study comparing morning and evening exercisers found no association with worse sleep in either group.
"Hitting the snooze button when you wake up is better than getting up when the alarm first goes off." We're all guilty of hitting that snooze button one too many times. Sleep disruptions of any sort are not optimal. Fragmenting your sleep, such as by hitting snooze, is associated with adverse outcomes, including decreased mental flexibility and subjective mood, sleep experts have said. It's better to set one alarm at the time you actually need to wake up.
"If you're having difficulties sleeping at night, taking a nap in the afternoon is a good way to get adequate sleep." Most of us look forward to a "siesta" or mid-afternoon nap. Sadly, this is false. According to a study in The Sleep Medicine Journal, frequent and even infrequent napping can be linked to elevated levels of inflammation in the body.
"Alcohol before bed will improve your sleep." Although alcohol might make you feel relaxed, it actually harms sleep quality. When you fall asleep, your brain goes through stages: NREM (non-rapid eye movement), composed of three stages, and finally REM (rapid eye movement). Alcohol has been shown to have an overall negative impact on sleep and delays the onset of REM sleep. Alcohol has also been shown to worsen symptoms of OSA.
"Watching television in bed is a good way to relax before sleep." A survey of U.S. adults found that 50% of respondents reported watching television in the 30-minute period leading up to bedtime. Evidence confirms a relation between television watchers and short sleepers. Screen time of any form exposes you to "artificial blue light." Blue wavelengths during natural day light are beneficial and boost attention. But artificial blue light from screens, especially before bedtime, suppresses the body's ability to secrete melatonin, according to a Harvard study. Look for ways to protect your eyes from the effects of blue light by avoiding screens two hours before bed or using blue-light-blocking glasses.
Keep these debunked myths in mind next time you decide to take a nap or watch your favorite Netflix show right before bed, and remember how much better you feel the next day.
"Sleep is important to health," Girardin Jean Louis, a population health expert, told ABC News. "And there needs to be greater effort to inform the public regarding this important public health issue."
Nura Orra is a physician at the MetroHealth Medical Center in Cleveland and is a member of the ABC news medical unit.