We live in a 24-hour world that, thanks to technology, never has to go dark. But there is a thing as too much light—too much blue light.
Blue light isn’t always bad. It’s what makes the sky blue. The sun is the primary source of blue light, which has benefits including increasing alertness, regulating circadian rhythm, elevating mood, and helping with memory.
The problem comes when the sun goes down and we don’t put our smartphones, tablets, computers, and TVS to sleep. Artificial sources of light have a higher concentration of blue light than natural light. Blue light affects levels of melatonin—the hormone that helps us sleep–more than any other wavelength. Chronic exposure to blue light at night can decrease the production of melatonin and disrupt your circadian rhythm—your body’s natural clock.
This causes more than an upset sleep schedule. Researchers have linked exposure to blue light at night (and working at night) to certain cancers, heart disease, diabetes, obesity, and a greater risk for depression. Exposure to blue light can be a factor in age-related macular degeneration.
To avoid overexposure, turn off your devices at least an hour before bedtime. If you can’t put your devices down, applications are available that change the colors of your displays to warmer colors at night, such as Windows Night Light or Mac Night Shift. Blue light filtering glasses are also available.