There has been a growing push in recent years to raise awareness about the dangers of drunk driving and texting while driving. Such behaviors pose real threats to safety on the road and lead to high numbers of unnecessary tragedies each year.

Even if you’ve never driven while tipsy, and you always wait until you’re parked to check your phone messages, there is another type of driving behavior that nearly all of us have been guilty of: drowsy driving.

Maybe you were up all night with insomnia, and you dragged yourself to work before having your first cup of coffee. Maybe you just got off a 12-hour shift and are attempting to prop your eyelids open as you make your way home. Driving while in an exhausted state is something most of us do at least occasionally. And it’s fairly socially accepted. When you recognize you’re seriously fatigued, postponing your trip or finding another mode of transportation probably doesn’t even occur to you. But it should.

Drowsy vs. drunk

A recent study in the journal Occupational and Environmental Medicine made an important discovery: it found that driving while sleepy can actually inhibit your abilities behind the wheel as much as driving while intoxicated. In fact, missing sleep for just 17 consecutive hours produces equivalent impairment to a blood alcohol concentration (BAC) of 0.05. The effect is exacerbated with increased sleep deprivation.

The consequences of driving with insufficient sleep can be devastating. The National Highway Traffic Safety Administration estimates that drowsy drivers cause upwards of 100,000 crashes each year—resulting in 40,000 injuries and 1,500 deaths.

It’s important to make sure you’re sober and free of distractions each time you get behind the wheel—but it’s equally valuable to ensure you’re alert enough to drive safely. Thoughtful decision making prior to beginning your trip can help prevent tragedy on the road.