Traffic safety officials regularly warn us of the risks of driving while drunk or distracted, but getting behind the wheel when sleepy can be just as dangerous.

A report released Tuesday by the AAA Foundation for Traffic Safety suggests that drivers who sleep only five or six hours in a 24-hour period are twice as likely to crash as drivers who get seven hours of sleep or more. Drivers in the study who got only four or five hours of shut-eye had four times the crash rate — close to what's seen among drunken drivers.

Related links:
Final report: https://www.aaafoundation.org/sites/default/files/AcuteSleepDeprivationCrashRisk.pdf
Fact Sheet: https://www.aaafoundation.org/sites/default/files/AcuteSleepDeprivationCrashRiskFS.pdf