Why too much blue light at night can make it hard to sleep

Being around blue light at night, like from phones or screens, might keep your body from making the sleep hormone melatonin because it keeps stress hormone levels high, making it harder to fall and stay asleep.

Being around too much blue light at night, like from phones or lamps, can mess with your sleep and your body's internal clock, making it harder to fall asleep and feel rested.

Wearing blue light-blocking glasses, using screen filters, adjusting room lighting, and managing screen time may help reduce the negative effects of blue light on your sleep and body clock — but we still need more research to be sure how well these work for everyone.

Too much blue light messing with your sleep clock might also be bad for your mood, brain, and metabolism — not just your sleep.