Use iPhone Night Shift All Day to Reduce Blue Light

We are exposed to more artificial light sources than ever, and the most ubiquitous of them all is the phone we carry around in our pockets.

We have to be careful of the unnatural brightness and timing of light exposure in our modern lives. Before the advent of electricity, when the sun set in the evening it was dark, and if we did have light it was either fires or lanterns – both of which have low brightness and a "warm" color temperature made up of red and orange hues, similar to a sunset.

Blue light wakes up your brain

Melatonin is a hormone made by the pineal gland in your brain that helps your body know when to sleep. Blue light from our digital devices mimics what the brain sees at noon on a sunny day, and your brain interprets this as sunlight and suppresses melatonin production.[1][2]

To maximize your health you have to be disciplined about when you start to wind down in the evening and limit light exposure (especially blue light) before bedtime.

Start to think about your phone as a "sunlight device". So when you're lying in bed at midnight glancing at your phone, blasting blue light into your eyes, it's no wonder you can't get to sleep.

Needless to say, sleep is vital to our overall health. Not getting enough sleep has been linked to depression, anxiety, diabetes, and obesity, among other things.[3][4][5]

What is iPhone Night Shift?

Fortunately, there is a way you can reduce blue light exposure on your iPhone. Apple recently introduced a feature called Night Shift that changes the colors on your screen towards a warmer hue.

When Night Shift turns on, the screen noticeably becomes more orange, kind of like a sunset on a nice summer evening. This reduces blue light exposure and means looking at your phone won't affect your melatonin production as much.[6]

How to keep Night Shift on constantly

To turn on Night Shift, go to Settings / Display & Brightness / Night shift. You will see the screen below.

You can schedule night shift to turn on any time you'd like, but I recommend keeping it on all day. We get plenty of blue light and this way you never have to worry about looking at your phone.

To trick your iPhone into doing this, simply choose a time period, for example, from 4:00 AM to 3:59 AM the following morning. This way your phone will turn off Night Shift for one minute a day, and then immediately turn back on.

For some reason, choosing a time from 4:00 AM to 4:00 AM the following day doesn't work. You need to have a one minute gap.

iPhone trick to keep Night Shift on all day and reduce your blue light exposure
Trick your iPhone into keeping Night Shift on all day and reduce your blue light exposure

Although the screen may seem too orange at first, your eyes will quickly adjust. I don't even notice it anymore.

Pairing this iPhone trick with glasses that block blue light gave me huge improvements in evening sleepiness and my ability to fall and stay asleep.

Brightness matters too

Studies have been done on Apple's Night Shift feature and they showed that, while using Night Shift suppressed less melatonin production, it still had a noticeable effect and screen brightness played a role.[6]

The takeaway is: don't watch TV, look at your computer screen, or any bright lights in the evening, especially blue ones. Use iPhone Night Shift all day, and similar features for your computer and Android devices. And wear blue-light blocking glasses. This is how we can prevent some of the unnatural effects of light in our daily lives.