Artificial light is one of the biggest causes of sleep deprivation in modern humans, but there's some special witch magic in smartphone and tablet light that really messes with our sleep cycle — essentially forcing us to stay awake by convincing our bodies that it's actually morning.
Smartphones do this because they let off bright blue light.
"One of the best biological cues we have to what time of day it is is light. And it turns out that blue light in particular is very effective at basically predicting when morning is," chemistry researcher Brian Zoltowski says in the video below, from the American Chemical Society.
In the evenings, there's more red light than blue light, which signals your body to prep for bed. The red light does this by interacting with the protein melanopsin in cells deep inside your eyes — ones that are specifically made to regulate circadian rhythms and don't play a role in how we see.
When the light hits this protein, it changes, and these cells send a signal to the "master clock" of the brain, which dictates when we wake and when we get sleepy. When it sends a "wake up" signal at night, our body clock gets screwed up.
The solution to a screwed up body clock? Force yourself to do things at the right time of the day — eating at mealtimes, getting to bed at a normal time, and getting up at a good time as well. And, of course, avoid that blue light at night.
Watch the whole video, from ACS Reactions on YouTube:
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