That doesn’t necessarily mean it’s a good idea to use technology before bed—any bright light right before sleep can mess with circadian rhythms, and firing off last-minute emails is unlikely to lull you to sleep—but blue light may not be as universally bad for slumber as people think. There is a valid scientific basis to the idea that blue light interrupts sleep, since research consistently shows that light of any kind suppresses melatonin and blue light may do so to an especially extreme degree. Blue light stimulates parts of the brain that make us feel alert, elevating our body temperature and heart rate. Blue light has the most power among the spectrum of visible lights to affect your internal sleep-wake body clock called circadian rhythm. So what’s the best way to get a full eight hours each night? And there are additional caveats to this particular paper, says Dr. Cathy Goldstein, a sleep specialist at Michigan Medicine. It changes the background from white to black. In Wyatt’s view, recommendations around limiting blue light have far outpaced science around its effects. University of California, Davis Health: âIs Blue Light from Your Cell Phone, TV Bad for Your Health?â, American Academy of Ophthalmology: âShould You Be Worried About Blue Light?â âShould You Use Night Mode to Reduce Blue Light?â, American Optometric Association: âIn the Dark on Blue Light?â, Proceedings of the National Academy of Sciences: âEvening Use of Light-Emitting eReaders Negatively Affects Sleep, Circadian Timing, and Next-Morning Alertness.â, Harvard Health: âBlue Light Has a Dark Side.â, Chronobiology International: âAmber Lenses to Block Blue Light and Improve Sleep.â, Molecular Vision: âEffects of blue Light on the Circadian System and Eye Physiology.â, International Society for Chronobiology: âAmber lenses to block blue light and improve sleep: a randomized trial.â, PLoS One: âBlue-Light Filtering Spectacle Lenses: Optical and Clinical Performances.â, Journal of Psychiatric Research: âBlocking nocturnal blue light for insomnia: A randomized controlled trial.â. How Blue Light Hurts Sleep Your eyes aren’t good at blocking blue light. © 2005 - 2019 WebMD LLC. Vote Now, You can unsubscribe at any time. Save on the cover price & free e-Gift card for Giftees! '” Wyatt says. Here’s what experts say about blue light. And finally, though mice are frequently used in sleep research, Goldstein notes that since the rodents are nocturnal, they may respond differently to light than humans do. Researchers compared the influence of blue light and green light … But in terms of eye health, there’s no reason to spend your time and money looking for blue-light-filtering glasses or gadgets, says Dr. Matthew Gardiner, an ophthalmologist at Massachusetts Eye and Ear. In other words, though it may be a potential trigger for health issues, its impact has been blown way out of proportion. How blue light interferes with sleep . Baby Nursery Light. Blue light therapy devices may help treat depression, and blue light bulbs have been shown to reduce fatigue and improve the mood, performance, and sleep of office workers (12, 13, 14). Smart Grocery Shopping When You Have Diabetes, Surprising Things You Didn't Know About Dogs and Cats, Coronavirus in Context: Interviews With Experts. Goldstein adds that the spectrum of light isn’t the only thing that matters—so do brightness, and duration of exposure. In an evening, the blue light that emits from devices (including TVs) … LEDs give off more blue light than fluorescent bulbs. By signing up you are agreeing to our, A Sleep Storyteller Reveals Her Secrets for Drifting Off Naturally. Exposure to all colors of light helps control your naturalÂ sleep-and-wake cycle, or circadian rhythm. But Wyatt says most human research done in this field hasn’t been representative of the way the average person is exposed to blue light. For sleep, Wyatt says the evidence isn’t strong enough to issue a blanket recommendation on blue light. Similar to sunlight, blue light has been shown to suppress the release of melatonin, a hormone produced by the pineal gland in the brain that makes you feel sleepy. Write to Jamie Ducharme at email@example.com. After exposing mice to lights that were different in hue but equal brightness and assessing their subsequent activity, the researchers concluded that yellow light actually seems to disturb sleep more than blue. Goldstein agrees that blue light research isn’t as conclusive as it’s often portrayed, but says there’s also no reason not to use night-mode filters on electronics if you find them helpful. WebMD does not provide medical advice, diagnosis or treatment. During the day, blue light can improve performance and attention, tuning our circadian rhythm and setting us up for a better night’s sleep after the sun sets. Personal preference plays a role, too. The light from your devices often appears white. “Blue light has become the gluten of the sleep world,” Goldstein says with a laugh. Warm-toned light, they hypothesized, could trick the body into thinking it’s daytime, while cooler blue light more closely mimics twilight. All kinds of light can interfere with melatonin production, but blue light has the greater impact, according to an article by Harvard Medical School researchers. How blue light interferes with sleep . A big reason for your mood is the high-intensity blue light coming from the sun. Other ways include: Blue light-blocking glasses. “In over 20 years of practicing sleep medicine, I have never had a patient come to me and say, ‘Hey, doc, can you help me fall asleep 10 minutes faster? Both natural and artificial blue light can boost your alertness and mental sharpness. More so than any other color, blue light messes with your bodyâs ability to prepare for sleep because it blocksÂ aÂ hormoneÂ calledÂ melatoninÂ that makes you sleepy. 12 reasons why you're tired -- and how to fight them. And both emit more blue light than energy-hungry incandescent bulbs, which are being phased out. Finally, research is pretty definitive on the fact that a dark room is the best environment for sleep, so it’s smart to block out light sources when it’s actually time for bed. The simplest way to lower your exposure to artificial blue light is to turn off your smartphone, TV, and other gadgets well before bedtime. So almost all of it passes straight through to the back of your retina, which helps your brain translate light into images. Use a dim red lightbulbÂ as a nightlight. Worse yet, nine out of 10 Americans admit to reaching for an electronic device at least several nights each week shortly beforeÂ bedtime. Sign up to receive the top stories you need to know now on politics, health and more, © 2020 TIME USA, LLC. But they can give off wavelengths in the range of 400 to 490 nanometers, which is blue light. Take that iPad study, for example. Wyatt suggests keeping your room at a cool 65° to 68° Fahrenheit, limiting intermittent noise and sticking to roughly the same sleep and wake times each day to get quality rest. Amber or brown-tinted lenses may help best. That is, most experimental conditions don’t correspond to the average person’s day, and even then they often result in only tiny changes in sleep. How does blue light affect sleep? Animal studies should always be taken with a grain of salt, as they often do not translate directly to human behavior. But that doesn’t mean blue light is evil. Your body is dictated by its circadian rhythms, a set of time-dependent physical, mental and behavioral shifts. Just remember to turn down the brightness and avoid hours of aimless scrolling, she says. That could be an invitation forÂ insomnia. Nighttime light exposure can confuse this process, suppressing melatonin production and keeping you up longer. The study was surprising, given the widespread thinking around blue light, but it wasn’t unprecedented. Studies have suggested that blue light is an especially powerful melatonin suppressant. Theyâre widely sold online. While some people report improvements in eye-strain or headaches after using these products, Gardiner says there’s no research to suggest blue light damages your eyes. 1600K Sleep Aid Emits Only 0.06% Blue Light for Healthy Sleep. 7W LED, 45W Replacement by Hooga. “For this to get extrapolated to saying ‘blue light at night isn’t bad for you’ is a little bit of an extension,” Goldstein says. Wyatt notes that some people feel relaxed and sleepy after watching television, while others feel wide-awake after flipping through a page-turning book. All rights reserved. But in December, a group of researchers at the University of Manchester in the U.K. published a paper in Current Biology challenging that notion. There are plenty of reasons other than sleeplessness to not spend all your time staring at screens, from possible mental health consequences to their correlation with a sedentary lifestyle. Have you ever woken up to bright morning skies feeling energized? Melanopsin, the pigment that helps eye cells assess light brightness, is particularly sensitive to shorter, cooler wavelengths like blue light, which some research says means blue light may affect the body more dramatically than other hues. This is often called night mode or dark mode. It’s become a virtually unchallenged piece of conventional wisdom that exposure to blue light—the type emitted by electronic device screens—is bad for sleep. Light is the most powerful cue for shifting the phase or resetting the time of the circadian clock. That thinking has spurred a mini-industry of innovations meant to stop those effects, like warm-toned “night mode” settings on gadgets and glasses that claim to block blue light. This process is dependent upon melatonin, a hormone secreted when it’s dark outside. Americans spend an average of 7 hours a day on electronic devices. One highly cited study from 2014 showed that using a blue-light-emitting iPad before bed suppresses melatonin, while reading a traditional book does not. Dim the brightnessÂ on your devices. IPad readers started producing melatonin 1.5 hours later than usual the next day, and experienced REM sleep—the phase during which dreams occur and memories are consolidated—once they conked out, the study found. The most obvious circadian rhythm is the one that drives you to be tired at night and alert during the day. The researchers looked specifically at cones in the animals’ eyes, which detect color, instead of melanopsin, which senses light and is central to the issue of melatonin secretion. Swap light bulbs. Set an alarmÂ for 1 hour before bed to remind yourself to quit using devices. “You can’t have your blue light filter on, and then have your phone or your tablet at maximal brightness” and expect to drift right off with no problem. “You can’t just worry about spectrum alone,” she says. Red is the color that least affects your circadian rhythm. 2-Pack 4.4 out of 5 stars 109 Cut back on screen timeÂ starting 2-3 hours before bed. While it did show that bedtime exposure to blue light through an iPad can suppress melatonin, Wyatt notes that people who read on their devices for hours took only 10 minutes longer to fall asleep than paper book readers. Who Should Be TIME’s Person of the Year for 2020? Some researchers have argued that, while electronics can keep you up because of their bright lights and ability to time-suck, blue light isn’t necessarily the problem. Sign Up to Receive Our Free Coroanvirus Newsletter. Bottom line: Youâre less drowsy than usual at night, and it takes you longer to fall asleep. “We put the cart so far ahead of the horse” with blue light, agrees James Wyatt, who directs sleep disorders and sleep-wake research at Rush University Medical Center. How Long Does Coronavirus Live On Surfaces? Sleep Light Bulb, Blue Light Blocking Amber Night Light. Taken together, Goldstein says these conditions mean the study’s results apply only to a very narrow set of circumstances and metrics. They also kept light levels dim, regardless of color, which may not reflect the bright lights of electronics. Among the visible light spectrum, blue wavelengths have the most powerful effect on yourÂ sleep-wake internal body clock. Effects of Blue Light on Sleep. Use of this site constitutes acceptance of our, Forget What You Think You Know About Blue Light and Sleep. They filter a lot of blue light from reaching yourÂ eyesÂ without making it harder to see the display. Properly-timed exposure to blue light can treat several sleep disorders. But too much of it may keep you awake when your body needs to wind down. YourÂ eyesÂ arenât good at blocking blue light. All kinds of light can interfere with melatonin production, but blue light has the greater impact, according to an article by Harvard Medical School researchers. All Rights Reserved. Install blue light-filtering appsÂ on smartphone, tablet, and computer screens. For sleep, Wyatt says the evidence isn’t strong enough to issue a blanket recommendation on blue light. Thatâs a lot of time staring at blue light. Researchers compared the influence of blue light and green light of similar brightness on melatonin for 6.5 hours of exposure. So almost all of it passes straight through to the back of your retina, which helpsÂ your brainÂ translate light into images. Writers at Harvard Health Publishing tell us that, “Until the advent of artificial lighting, the sun was the major source of lighting, and people spent their evenings in (relative) darkness.” Today, however, most of us are exposed to light (right devices and bulbs) right up until the point we go to sleep… “If you feel more comfortable, then that’s fine, but it does not do anything for the health of your eyes,” he says.