Culture
How Coffee Screws Up Your Sleep Cycle
A new study reveals how caffeine impacts circadian rhythms—but could actually help certain people sleep better.
You’ve surely heard that it’s not a good idea to chug a mug of coffee right before putting your pajamas on, or to watch Hulu on your cell phone as you drift off to sleep. But the precise mechanisms by which caffeine and bright light—partners in sleep-defying crime—disrupt circadian rhythms remained a little murky.
A new study, published today in Science Translational Medicine, investigated the effect of caffeine on these cycles. Over the course of 49 days, researchers compared the effects of caffeine to the impact of bright light (such as from computers or cellphones), which is already known to make it harder for us to produce melatonin, disrupting our rhythms and resulting in poorer sleep.