Can Using iPhone Night Shift Avoid Disrupting Your Sleep? | Beth's Blog

Can Using iPhone Night Shift Avoid Disrupting Your Sleep?

Happy Healthy Nonprofit, Resilience

Photo by Kris Krug

Note from Beth:  I’ve been presenting workshops on technology wellness and other ideas from the Happy Healthy Nonprofit. One of the most important aspects of self-care is getting a good night’s sleep. The best way to do this is to stop using your mobile phone too close to bedtime or kick it out of your bedroom entirely.  There are a few different ways technically can help, including these blue light blocking glasses.  The iPhone now has a feature called “Night Shift” that changes the brightness of your mobile phone screen to warmer tones, presumably so that looking at your phone before won’t get in the way of a goodnight’s sleep. But, does it really work?

I invited Sarah Johnson who a researcher for, a site devoted to covering sleep science to investigate .

Guest Post: Can iPhone Night Shift Avoid Disrupting Your Sleep

The Night Shift feature, which Apple integrated on iOS 9.3 devices, addresses the growing concern of the effects of screen time on sleep. Of course, this feature isn’t a sleep solution for everyone. It does address a growing issue that will only continue as technology becomes more integrated into daily life. To better understand how to use this feature, we first need to look at how light affects the human sleep cycle.

Light and the Sleep-Wake Cycle

The human body uses circadian rhythms, 24-hour repeating cycles, to control the release of hormones, cell regeneration, and the sleep-wake cycle amongst other body functions. The circadian region of the brain connects directly to special photoreceptors in the eye called ganglion cells. These cells absorb the blue spectrum light that filters through the Earth’s atmosphere from the sun. The ganglion cells then send signals directly to the circadian region of the brain.

High levels of blue spectrum light suppress sleep hormones. Which makes sense since you’re most likely to be exposed to natural light during the morning and afternoon when you need to be awake. As natural light levels progressively lower, you begin to feel sleepier as sleep hormone levels increase. Once it’s completely dark, your body is fully prepared for a good night’s rest.

The Impact of Artificial Light

Today, there are many artificial light sources, like cell phones, that also emit blue spectrum light. Though these light sources aren’t exactly like sunlight, they are similar enough to cause a suppression of sleep hormones.

A lack of sleep hormones delays the onset of sleep because you simply don’t feel tired even though your body needs rest. You can reverse these effects by turning off your devices two to three hours before you want to go to bed.

However, many people check their email, scan through social media, or read books on their cell phones while in bed. Apple’s night shift feature enters the market as a way to reduce the sleep-depriving effects of a bright screen.

Why and How to Use the Night Shift Feature

The Night Shift feature acts almost like a pair of blue light blocking sunglasses. It gets rid of the blue light you don’t need and lets through an orange/red spectrum light that doesn’t directly influence the circadian rhythms.

You can use the Night Shift feature in one of two ways.

1) To manually turn on Night Shift go to Settings > Display & Brightness > Night Shift and turn it on. You’ll need to turn it on at least two to three hours before bed to prevent blue light from affecting your sleep cycle.

2) For automatic Night Shift, follow the same steps as above to get to Night Shift control. But this time fill in the “from” and “to” with the time period in which you want Night Shift to function.

(Just a reminder that it’s not just light from a cell phone that affects your sleep. The stimulation from the content can be just as disruptive.)

The Night Shift feature may not fix all of your sleep problems, but it removes an obstacle the could stand between you and a full night’s rest. Give it a try and see if you’re not feeling sleepier when your bedtime rolls around.

Sara Westgreen is a researcher for the sleep science hub She sleeps on a king size bed in Texas, where she defends her territory against cats all night. A mother of three, she enjoys beer, board games, and getting as much sleep as she can get her hands on.

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