Will the “night Modes” on My Smartphone or Tablet Help Me Sleep Better?
Dear Lifehacker, I love using my smartphone and tablet in bed. I know screen time before bed is bad for my sleep , but will features like Apple Night Shift and Android N Night Mode help me sleep better and let me read in bed at the same time?
Regards, Browser for the night
Dear columnist, before bed! Let’s start with what we know: Exposing your eyes to light interferes with your body’s natural ability to produce melatonin , a hormone produced by your pineal gland that helps you fall asleep. When you disrupt this process, your circadian rhythm (or “internal clock”) is reset. We must sleep in the dark, and unnatural light sources make it difficult for us. In fact, even visually impaired people have a similar response to ambient light, according to one study published in the Journal of Endocrinology and Metabolism .
Smartphones and tablets are just as damaging to your brain. Light can either speed up or delay your circadian rhythm, and even the small amount of light produced by your screen propels it (even in a dark room). Basically, your body thinks you are looking at sunlight (even though you consciously know it is night) and reacts accordingly. Countless studies (like the one mentioned above) have shown that the type of bright blue light emitted from your devices is especially damaging because its short wavelength is what tells your brain to be alert and not at rest. In fact, one Swedish study, published in the One PLOS , suggests that blue light may be even better than coffee, to make people more aware .
Less blue light before bed is good.
That’s where features like the recently announced Apple Night Shift and the upcoming Android N Night Mode come in. They automatically detect when you’re approaching sleep, dim the brightness, and adjust the color temperature of your display to minimize the amount of blue light. This gives your screen a warmer and darker color palette that may appear less crisp, but much more pleasing to the eye. Ideally, you will be able to stare at your phone or tablet as much as you want, because overall you get less light and no problematic blue light.
The logic sounds at first glance. By removing the nasty blue material, you won’t let your device trick your brain into thinking it’s time to be awake and stop producing melatonin. There is evidence to support this. Numerous studies show that avoiding blue light at night with orange lenses blocking blue color has a positive effect on sleep patterns. For example, one study published in the Journal of Adolescent Health found that teenage boys can sleep better withblueblocked glasses at bedtime, and another studypublished in Chronobiology International found similar results with adults. In the study, one group was given UV-blocking glasses and the other group was given blue-blockers. The blue blocking group reported falling asleep more easily compared to the UV blocking group (but it is important to note that compared to the teen test, adult participants used the devices at bedtime significantly less initially).
Night modes reduce the amount of blue light (but this may not save your sleep)
However, we don’t know for sure if features like Night Shift and Night Mode will suffice, or if they will have the same effect in the long run as blue block glasses. There hasn’t been any long term research into these features and their effect on people’s sleep, or apps like f.lux or Twilight that many people use today to do the same. We can speculate that changing the color palette of your device’s screen towards higher temperatures will reduce your exposure to blue light, which can help you avoid disrupting melatonin production and disrupting your circadian rhythm, but we don’t know for sure yet.
However, there have been studies that have tested color temperature and its effect on activity, sleepiness, and sleep quality. One studypublished in the Journal of Physiological Anthropology and Applied Sciences suggests that color temperature is more important than light levels when it comes to the effect of light on your sleep. Low-temperature lighting (warmer colors like reds and oranges) made participants more sleepy and less active despite the brightness level (good news for your devices with night modes), according to a study. A separate studypublished in the same journal suggests that color temperature can also affect the quality of your sleep. The researchers found evidence that the presence of high color temperatures (colder colors such as blue and white) before and during sleep adversely affected participants’ overall rest during the trials. Unfortunately, both of these studies were very small (only eight men in the first study and seven men in the second), so it’s hard to say how this will change when it comes to the millions of devices in the hands of people.
Apple Night Shift and Android Night Mode certainly seem to be heading in the right direction. However, they may not be the panacea that Apple and Google make of them. Your devices will still emit light, and while these features may make it easier to fall asleep on a physiological level, they can distract you on a psychological level (especially if you keep getting notified ). If you want to use your device in bed, it certainly doesn’t hurt; they are promising. Just keep your expectations in check and remember that there are many other factors when it comes to sleeping well .
Regards, Lifehacker