That glow from your smartphone may be keeping you up at night more than you realize.
Avoiding the color cyan--a cross between blue and green--may help you sleep better, according to researchers at the University of Manchester.
BBC.com reported that researchers found that the high levels of cyan keep people awake and that people could feel the impact even if changes were not visible to their eyes.
The researchers want to create devices for screens and phones that limit or eliminate cyan levels.
Sleep researchers know that color and sleep are related. They've identified blue light as a cause for sleep delay, and have created "night mode" settings for phone and laptops.
This new research focuses specifically on cyan, though.
The researchers measured levels of melatonin--the sleep hormone--in people's saliva based on their exposure to more or less cyan. They found that the body reacted to the change, even if the eyes didn't detect it.
Professor Rob Lucas, one of the team's lead researchers at the University of Manchester, along with Dr. Annette Allen said, "This outcome is exciting because it that tells us that regulating exposure to cyan light alone, without changing color, can influence how sleepy we feel."
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