Adults should aim for at least 7–8 hours of quality sleep before driving to avoid fatigue. Driving on less than 5 hours of sleep is considered highly dangerous—equivalent to driving over the legal alcohol limit—and significantly increases crash risk. Fatigue-related crashes are often fatal.
1 Specifically, healthy drivers who have slept for two hours or less in the preceding 24 hours are not fit to operate a motor vehicle. NSF experts further agreed that most healthy drivers would likely be impaired with only 3 to 5 hours of sleep during the prior 24 hours.
After synthesising the findings of 61 unique studies, we found having less than four to five hours of sleep in the previous 24 hours is associated with an approximate doubling of the risk of a vehicle crash. This is the same risk of a crash seen when drivers have a blood alcohol concentration of 0.05%.
Getting adequate sleep on a daily basis is the only true way to protect yourself against the risks of driving when you're drowsy. Experts urge consumers to make it a priority to get seven to eight hours of sleep per night.
Make sure to get at least seven hours of sleep before heading off on a long drive–the risk of accident increases dramatically as sleep time within the prior 24 hours is reduced. Stop for a nap if you need to–even 20-30 minutes can make a difference for many people.
How much sleep do you really need? | Sleeping with Science, a TED series
What do naps do for driving?
Cognitive reset: Short naps restore alertness, improve reaction times, and sharpen memory, without the grogginess long naps can bring. Safe and effective: Research consistently shows that power naps significantly lower the risk of accidents tied to drowsy driving.
For adults, getting less than seven hours of sleep a night on a regular basis has been linked with poor health, including weight gain, having a body mass index of 30 or higher, diabetes, high blood pressure, heart disease, stroke, and depression.
But making a decision about driving isn't so much disease-specific as it is about driving performance, Dr. Kennedy says. When Parkinson's or arthritis causes stiffness that's so severe it impairs reaction time, that's a sign you should stop driving. Another red flag is whether you've reached age 85.
What is the minimum amount of sleep you need for a long drive?
How do I avoid fatigue? Get enough quality sleep before you begin driving. Be sure to have seven to eight hours of uninterrupted sleep before your trip.
Key Findings. Results show that an estimated 17.6% of all fatal crashes in years 2017–2021 involved a drowsy driver. Over the 5-year study period, an estimated 29,834 people were killed in crashes that involved drowsy drivers.
If you're feeling fatigued, pull over and take a short nap or 'powernap'. Research shows that even a small sleep of 15 to 20 minutes can temporarily lessen the effects of fatigue for up to 1 to 2 hours. If possible, avoid overnight driving, or driving when you would normally be asleep.
The Highway Code recommends that drivers and riders should take a 15-minute break every two hours. Avoid periods of peak traffic flow if you can and plan around seasonal variations on routes.
You might start feeling tired and "old" due to natural bodily changes peaking around your 40s and 50s (perimenopause, hormonal shifts, slower metabolism/blood flow), but significant fatigue (feeling run-down, not just sleepy) often points to lifestyle (poor sleep, diet, stress) or underlying issues, with physical resilience decreasing more noticeably after 60, making it crucial to address these factors for energy levels, notes this article from Top Doctors and this blog from Be You Health Studios.
The bare minimum of sleep needed to live, not just thrive, is 4 hours per 24-hour period. Seven to 9 hours of sleep are needed for health, renewal, learning, and memory.
Research suggests that oversleeping can make people groggy and cognitively impaired. Studies suggest oversleeping is associated with increased risks of cardiovascular disease, diabetes and having obesity as much as undersleeping because toxins and inflammatory markers build up.
10 hours before bed: No more caffeine. 3 hours before bed: No more food or alcohol. 2 hours before bed: No more work. 1 hour before bed: No more screen time (shut off all phones, TVs and computers).
If you notice any of the following symptoms, you may be at risk of microsleep: Feeling drained after waking up and craving more sleep. Feeling unusually tired persistently during the day. Dizziness, blurred vision, difficulty keeping your eyes open, not noticing traffic lights.
