What Sleeping with the TV on Does to Your Body, Says Science

Here are a few reasons why you shouldn't fall asleep watching "Friends."

Falling asleep in front of the television is practically a modern rite of passage for many. It's even a requirement in some circumstances. According to a national survey conducted by LG Electronics, over two-thirds of Americans (61%) typically fall asleep while watching television. According to a study published in the journal Behavioral Sleep Medicine, 31% of Americans regard their television as a "sleep help." 

Why have so many of our favorite TV episodes become bedtime stories? It's most probably connected to our difficulty to disconnect. According to research conducted by the National Sleep Foundation and published in the Journal of Clinical Sleep Medicine, nine out of ten Americans use some electronic device in the hour before bed, with 60 percent stating that their preferred device is the television. With those numbers in mind, it's no surprise that so many people fall asleep in the middle of an episode. 

So, what exactly is the big deal? Who cares if Netflix bits are chirping in the background if it helps you drift off to a pleasant slumber? While it's true that watching TV helps many of us calm and relax after a long day, sleeping with the TV on could be harming you and your sleep quality more than you know. Are you curious about what happens to your body when you sleep with the television on? Continue reading to find out. 

1. Your Subconscious Continues Tuning In 

While you may fall asleep in front of the TV at some time, your subconscious mind is still listening. Your brain is still absorbing all that information as the characters talk and plotlines develop. "Surprisingly, even if you sleep with the TV on, your brain still hears all of the sounds coming from the TV, putting extra stress on your brain at a time when it needs to relax. So it's having a negative influence on both your mental and physical health, "Amelia Alvin, MD, a psychiatrist at the Mango Clinic, adds. 

Unsurprisingly, falling asleep in a horror film makes things worse. "Watching disturbing TV shows or movies can sometimes upset you since it affects your thinking," Alvin explains. "So, either it won't let you sleep soundly, or it'll show up in your dreams and unconscious thoughts, disturbing your sleep." 

This concept is supported by research published in the journal Dreaming. The study's authors discovered that those who watch violent TV shows within 90 minutes of going to bed are 13 times more likely to experience a nightmare than those who don't watch TV or watch something lighter like a sitcom. 

2. Your Melatonin Levels Drop 

When the sun sets each night, our bodies produce a significant amount of the hormone melatonin. When this happens, the body's melatonin levels rise, indicating that it's time to sleep. Unfortunately, the blue light emitted by electronics such as televisions, laptops, and cellphones can disrupt the body's natural clock and decrease melatonin production. 

This usually leads to worse overall sleep quality and a higher chance of waking up repeatedly during the night. Furthermore, getting into the deepest (and probably most crucial) stages of sleep is much more difficult. 

"Light exposure before bed disturbs the production of melatonin in your body and also affects the ability of your internal clock to tell time, with the TV light signaling to your body that it is still waking time," says Robyn South, Relations Manager at SleepAdvisor.org. "Constant light can keep you from getting into the deep stages of sleep, which are important for our healing and information-processing abilities to be blocked. You'll probably feel exhausted the rest of the day if you don't get that deep sleep." 

3. Your Sleep Debt Grows 

Many people dislike the word "debt," and with good reason: no one appreciates paying off an enormous responsibility, bill, or loan. Sleep debt is a genuine phenomenon. We don't usually associate sleep with debt, but it is. The Sleep Foundation defines sleep debt as the time gap between the quantity of sleep one requires and the amount. This means that watching a few more episodes of your favorite TV show right before bed might soon add up to large sleep debt. 

A lot of research has found a link between watching TV for sleep and having more sleep debt. According to a study published in the scientific journal Sleep, one of the leading causes of Americans not getting enough sleep is watching television. Additionally, another study published in the Journal of Clinical Sleep Medicine found a strong link between binge-watching habits and poor sleep quality, increased exhaustion, and increased symptoms of insomnia in general. 

4. You May Put on a Few Pounds 

Many readers may be surprised by this effect, but there is reason to believe that sleeping with the TV on could be bad for waistlines all across the country. According to a study published in JAMA Internal Medicine, women who sleep with artificial light (such as the glow of a TV screen) in their bedroom may be at a higher risk of obesity. Over five years, study participants who slept with their television on were 17 percent more likely to gain an average of 11 pounds. 

Notably, the link between watching TV while sleeping and weight gain held regardless of whether the women were receiving enough sleep. In other words, it didn't matter whether participants were insomniacs or slept soundly every night. They were more likely to acquire weight if they watched television all night. 

"Although poor sleep was related with obesity and weight growth on its own, it did not explain the relationships between exposure to artificial light while sleeping and weight," says corresponding author Dale Sandler, Ph.D. of the National Institute of Environmental Health Sciences Epidemiology Branch (NIEHS).

Related: A New Study Suggests The One Diet Change You'll Make After Better Sleep