Night mode 'better sleep' claims are nonsense, says university

Reducing the blue light does nothing to improve sleep.

Do you have your smartphone set to dim the screen in the evening to help you fall asleep better?

According to a study carried out by Brigham Young University (BYU), Apple's Night Shift and Android's Night Mode features do nothing.

"It's widely believed that the emitted blue light from phones disrupts melatonin secretion and sleep cycles," a BYU statement reads.

"To reduce this blue light emission and the strain on eyes, Apple introduced an iOS feature called Night Shift in 2016; a feature that adjusts the screen's colors to warmer hues after sunset. Android phones soon followed with a similar option, and now most smartphones have some sort of night mode function that claims to help users sleep better."

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To test these claims, BYU carried out a study. It took 167 "emerging adults (ages 18-24; 71.3% female)" and randomly assigned them to one of three groups. One group used an iPhone with Night Shift enabled for an hour before bedtime for seven consecutive nights, another used an iPhone without Night Shift for the seven consecutive nights, and another avoided smartphone use for the last hour before bedtime.

The conclusion?

There were no differences in sleep outcomes attributable to Night Shift.

On top of that, for those with normal sleep patterns, avoiding screen during that final hour resulted in better quality sleep than using an iPhone with Night Shift enabled did.

While only iPhone usage was tested, BYU believes that the same applies to Android devices with Night Mode.

Apple and Google no longer make claims that reducing blue light improves sleep (instead positioning it as a way to reduce eye strain), but as the time of writing, cached search results uncover past claims made by Google.

Do you dim your screen before bedtime? Do you feel that it helps? Let me know your thoughts in the comments below!

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