Sleep plays a crucial role in our physical and emotional health. If either the quantity or quality of our sleep is chronically below par, we put ourselves at increased risk of developing major long-term health problems, including high blood pressure, heart disease, type 2 diabetes and depression.
Poor sleep habits can affect our lives in the short term, too. When we’re tired, we don’t think as clearly, react as quickly, or learn as efficiently as we do when we’re rested. We’re also more likely to injure ourselves in some kind of accident.
Yet surveys have repeatedly shown that most of us — one-third of all American adults — fail to get a good night’s sleep on most nights.
One reason for our poor sleep habits may be a disinclination to take sleep seriously. And we may be doing that because we make assumptions about sleep that simply aren’t true.
Americans aren’t good at separating myths from fact about many health issues, and sleep is no different.
The most harmful myths
To get a better idea of the kinds of sleep myths that Americans harbor — and how those myths might be affecting the public’s health — a team of researchers searched more than 8,000 websites for common statements about healthy sleep habits. They then presented those statements to 10 leading sleep experts, including neuroscientists and chronobiologists.
The experts identified the 20 most common “myths” — beliefs about sleep that lack scientific evidence — among those statements. They then ranked them according to how false they were and how harmful they were to people’s health.
Those rankings are presented in a paper published online this week in the journal Sleep Health.
The authors of the paper point out that such myths aren’t innocuous. They can shape people’s behavior. Indeed, prior research has demonstrated that myths about obesity, smoking and the risk of breast cancer can lead not only to unhealthy behavior by individuals, but also to adverse public health decisions by policymakers.
“Sleep is a vital part of life that affects our productivity, mood and general health and well-being,” says Rebecca Robbins, the study’s lead author and a postdoctoral research at New York University, in a released statement. “Dispelling myths about sleep promotes healthier sleep habits which, in turn, promote overall better health.”
The top five myths
Here are the five myths that received the experts’ highest scores for posing the greatest risk to health:
- Many adults need only five or less hours of sleep for general health.
The evidence clearly shows this statement to be false, say Robbins and her co-authors. Adults need at least 7 hours of sleep per night for optimal physical and mental health. Yes, there are individuals — people from families with particular genetic mutations — who are able to function fully on less sleep, but they are rare.
- Although annoying for bed partners, loud snoring is mostly harmless.
Snoring is caused by partial obstruction of the upper airway during sleep. It’s a main symptom of obstructive sleep apnea — a condition that is associated with a heightened risk of high blood pressure and other types of cardiovascular disease.
But, as Robbins and her colleagues point out, snoring is associated with adverse health outcomes even when it isn’t a symptom of obstructive sleep apnea. “Thus, loud or bothersome snoring may be an indication that one needs to consult with a health care provider,” they warn.
- Your brain and body can learn to function just as well with less sleep.
After a few nights of not getting enough sleep, sensations of daytime sleepiness may plateau, but that doesn’t mean that the lack of sleep isn’t having an effect on people.
In fact, research shows just the opposite.
“Individuals might ‘adjust’ to consistent sleep debt and/or circadian misalignment but do so at the risk of serious health consequences,” Robbins and her colleagues write. “Consequently, evidence refutes the statement that the brain and body can adapt to function on less sleep.”
- Being able to fall asleep “anytime, anywhere” is a sign of a healthy sleep system.
Actually, it’s a sign of being chronically sleep-deprived. It may also be a sign of an underlying sleep problem, especially obstructive sleep apnea.
People who can fall asleep “anytime, anywhere” are also at increased risk of being involved in a motor vehicle crash, Robbins and her co-authors point out.
- Alcohol before bed will improve your sleep.
Drinking alcohol before bed may help people fall asleep faster, but many studies have shown it also disrupts the sleep cycle, often by delaying the onset of REM (dream) sleep.
The consumption of alcohol also worsens the symptoms of sleep apnea.
Here are the other 15 common sleep myths identified by the experts in the paper:
- Adults sleep more as they get older.
- If you can get it, more sleep is always better.
- One night of sleep deprivation will have lasting negative health consequences.
- In terms of your health, it does not matter what time of day you sleep.
- Lying in bed with your eyes closed is almost as good as sleeping.
- If you have difficulty falling asleep, it is best to stay in bed and try to fall back to sleep.
- A sound sleeper rarely moves at night.
- Hitting the snooze when you wake up is better than getting up when the alarm first goes off.
- If you are having difficulties sleeping, taking a nap in the afternoon is a good way to get adequate sleep.
- For sleeping, it is better to have a warmer bedroom than a cooler bedroom.
- Boredom can make you sleepy even if you got adequate sleep before.
- Watching television in bed is a good way to relax before sleep.
- Exercising within four hours of bedtime will disturb your sleep
- During sleep, the brain is not active.
- Remembering your dreams is a sign of a good night’s sleep.
For more information: You’ll find an abstract of the paper on the Sleep Health website, but the full version is, unfortunately, behind a paywall. You can, however, read about many of these sleep myths at the website for the National Sleep Foundation, which publishes the journal.