Drowsy driving causes thousands of car crashes a year and teen drivers say they are often sleepy behind the wheel.
In a new survey, teens reported high rates of drowsy driving. School and job commitments were the top factors keeping them up at night.
A corresponding survey of U.S. adult drivers showed similar trends.
Both teens and adults called drowsy driving "highly risky."
Previous studies have established that young people are at high risk for drowsy driving.
"What we see in our results this year is many teens, early in their driving experience, say they've already driven while drowsy. Overall, teens know the risks of drowsy driving, but don't think it's as risky as other forms of impaired driving,"Joseph Dzierzewski, a vice president of the National Sleep Foundation (NSF), said in a foundation news release.
"The good news is -- drowsy driving is preventable, and there's a lot we can teach our young drivers about the importance of getting the sleep they need before they get behind the wheel,"he added.
The NSF's 2023 Drowsy Driving Survey is part of its Drowsy Driving Prevention Week, a campaign to help Americans get the sleep they need and reduce numbers of sleep-deprived people behind the wheel.
Drowsy driving kills an estimated 6,400 people a year in the United States alone, according to the AAA Foundation for Traffic Safety. Crash and fatality data are likely underestimated, the sleep foundation said.
About 6 in 10 adult drivers said they had driven a car when they were so tired they had a hard time keeping their eyes open.
In their first two years of driving, 1 in 6 teens said they had already driven while drowsy. About 95% of teens consider drowsy driving risky, but most rate drunken, drugged and distracted driving as more dangerous.
Teen drivers with jobs are more than twice as likely as others to have driven when they could barely keep their eyes open.
To reduce the risk, the NSF says it's important to get the recommended amount of sleep -- seven to nine hours a night for adults, and eight to 10 for teens of driving age.
The group also offered these safety tips:
Plan long trips with a passenger who can look for early warning signs of drowsiness but also help with driving when needed. A good driving companion stays awake to talk to you and is aware of your alertness.
Schedule stops every 100 miles or two hours.
Be mindful of warning signs, such as frequent blinking and yawning, or difficulty with lane and speed control.
"At NSF, we're dedicated to helping everyone prioritize their sleep for health and safety,"the foundation's CEO, John Lopos, said in the news release. "Getting enough quality sleep to be your Best Slept Self is also important for our safe driving and responsibility on the road."
More information
The U.S. Centers for Disease Control and Prevention has more on getting enough sleep.
SOURCE: National Sleep Foundation, news release, Nov. 2, 2023