Image: AP

Drowsy driving is bad! But you knew that. Part of it what makes the problem a bit vexing though, is that no one intends, exactly, to be drowsy behind the wheel, which is probably why drowsy driving happens a lot more than we tend to think. How much more? According to AAA, it plays a role in one in 10 crashes. That’s a lot!

The research is particularly striking because, as AAA notes, drowsy driving is one of the most underreported causes of crash, presumably because you’re unlikely to admit to sleepiness you’ve just messed up. (You may also not be feeling sleepy following a collision.) But, in a new study released by AAA on Thursday, researchers analyzed the faces of drivers caught on dashboard cameras before crashes, calculating how long a person’s eyes stay closed as a measure of how drowsy they were. Based on those calculations, they say that drowsiness plays a role in 10 percent of all crashes.

Federal numbers, meanwhile, indicate that drowsiness is only a factor in up to two percent of crashes, suggesting that those numbers might be in need of a fresh look.

If you’re driving and you need to sleep, pull over and consider taking a nap. Wherever you’re going probably isn’t worth the risk.