You may have heard of night mode on your phone, but it's not something you usually use. It's very likely that device suggests you use this feature when you're up late and texting a friend. Switching from cooler to warmer shades of color on screen is supposed to help you sleep better.
However, according to a study conducted by Dr. Tim Brown and published in Current Biology, this is not the case. The research, conducted on mice, appears to contradict the idea that the blue light emitted by mobile phone screens disrupts sleep ,unlike warm light, which can actually affect it.
How then did the belief that blue light should be limited on the phone screen arise?
“Surely there was a valid scientific idea for why something like this would work”, says Brown. “It started about 20 years ago with the discovery of the role played by melanin – a light‑sensitive protein found in the eye – for regulating the body's clock.”
“The melanosome system is fundamentally there to detect brightness”, says Brown. Because melanosomes were better at detecting short-wavelength photons, it was considered biased toward blue light. In reality, the cone cells of the retina determine color. “The cone system also plays a role and does the opposite of what most people believe”, says Brown.
According to the study, brightness levels are more important than color when it comes to regulating the body clock. However, when the light is equally dim, blue is more relaxing than yellow.
If we think about it logically, it makes sense, since daylight is yellow while twilight is blue. And if nothing else, sunrise and sunset are a fairly reliable way for our body clock to know what time it is.
For now, we know this is happening in mice, since the study was conducted in them, but Brown says it's almost certain to happen in humans.
Sure, when your phone suggests that you switch to night mode, it might be a good sign that it's time to put it down and go to sleep.
Ultimately, it's not the colors or brightness of your phone screen that keeps you awake at night, but everything you can do with your phone. That's why the best way to avoid insomnia is to finally turn off your device !
