Elemental Light Week
Does Blue Light From Screens Really Ruin Sleep?
A recipe for managing the light in your life, at night and during the day
This story is a part of Elemental Light Week, a five-day series on what light does for your body, brain, and well-being.
Dreaded short-wavelength “blue” light from smartphones and other screens is supposedly creating a generation of sleepless zombies, spurring the creation of “night mode” apps that tamp down cold blue light and infuse smartphone screens with warmer yellows and reds. But as with zombies, some things appear different in the scientific light of day.
Studies reveal that light at night, especially blue light, can negatively affect sleep duration and quality. But some scientists say light from smartphones, tablets, computers, and TVs before bedtime is just one ingredient — and quite possibly a relatively minor one — in the recipe of environmental and behavioral monsters that keep people up at night.
The common recommendation to turn off screens two to three hours before bedtime remains good advice for kids and for anyone who struggles to fall asleep. But it fails to take into account the way humans are messing with their biological clocks by spending entire days indoors, in relatively dim…
