As tempting as it is to curl up with your phone before you go to bed, research has suggested that blue light, which is emitted by electronic devices, can disrupt our sleep patterns. But it's more complicated than researchers once thought: blue light's effects on sleep have to do with particular parts of the brain, the eye, and the body's circadian clock. And it turns out that the way blue light interacts with these parts of your body can also have a positive effect on your attention and memory. If your mom insists you wear your blue light glasses when you're looking on your phone, you might want to take that with a grain of salt.
Blue light, sleep expert Dr. Michael Breus Ph.D. tells Bustle, is the term for the wavelength of light between 460-490 nm (nanometers). It's the shortest wavelength of light, and we encounter it daily — but it's particularly prevalent in electronic devices that don't have light adjustments fitted. There's some evidence that it can be stimulating, and thus has the potential to mess up our body's internal clock. You shouldn't throw out all your blue light devices, though; some scientists now think that the presence of blue light isn't all that harmful, and may even have positive effects on sleep and wakefulness when used in the right ways. Here's the current science on blue light and sleep.