Blue Light From Your Phone Is Barely Touching Your Sleep

If you've been blaming your lousy sleep on your phone's bluish glow, you're probably picking the wrong villain. Sleep and circadian rhythm experts tell the BBC that, in normal life, the light from your phone, tablet, or laptop simply isn't bright enough to wreak the kind of havoc that lab studies have suggested. One review of nearly a dozen studies found screen light pushed sleep back by roughly nine minutes in the most severe cases. And a separate analysis estimated that a full day of blue light from digital devices adds up to less than a minute of outdoor daylight exposure, which really shouldn't affect your bedtime.

The New York Times notes that previous studies on blue light and sleep issues are out of date, featured small sample sizes, and were performed in lab environments that don't necessarily emulate the real world. So what could be messing you up at night? The scientists that the BBC spoke with point instead to how much light you get, and when. Strong light early in the day and a notable dimming in the evening seem to matter more for good sleep than micromanaging your phone's color temperature or forking over money for blue-blocking glasses. Less stimulating content before bed may also do more than any "night mode" toggle. For the full experiment—and practical tips—the full piece here.