Four factors you may not have considered that can affect how sleepy you are when driving

Four factors you may not have considered that can affect how sleepy you are when driving

Most of us understand that driving at night can be difficult. Not only is it harder to see, with headlights only providing a certain amount of visibility, but for the majority of drivers, nighttime is when we’re winding down towards sleep, if not yet actually in bed. Unfortunately, driving at night is sometimes necessary, whether that’s for work, coming back from vacation, or simply because you wanted to make the most of your daylight hours.

It’s easy to think that you can override your natural instincts and defy your usual sleeping pattern. And whilst that’s true to some extent, it does come at a cost – tiredness is one of the biggest killers on the road. But aside from pushing the boundaries when it comes to bedtime, what else can affect how sleepy you are, regardless of the time of day? Let’s take a look.


What you’ve eaten

Have you ever eaten a hearty meal and felt like you wanted to lie down and take a nap? It’s a familiar feeling after Thanksgiving or Christmas dinner, but it’s relevant in everyday life too. Being careful about what you eat in the lead up to a long drive can help ensure that you’re operating at a level where you can keep yourself, your passengers and other road users safe.
If you’ve woken up after a bad night’s sleep and need a boost of energy before your drive, try having a banana. They’re notoriously good as a natural sugar fuel, which is why they’re so popular with athletes – but tired drivers can benefit from them too. Or, if you’re after a sweet treat mid-way through your journey, try dark chocolate. The high cocoa content means that your blood flow may increase, providing more oxygen to your brain. In turn, this will boost your concentration.


Depression and anxiety

If you’re someone who struggles with depression or anxiety, you’ll know that these mental health conditions can directly affect your physical health too. Excessive worrying can keep you up at night or result in poor sleep quality, whereas depression can leave you feeling lethargic. Even if you’ve not been diagnosed with one of these conditions, short-term symptoms can have similar effects, making it harder to concentrate on everyday tasks such as driving.
If you think your mental health may affect how you drive, be sure to plan plenty of stops on the way, and remove as much time pressure as possible. That way, you can take the journey at your own pace, rather than watching the clock and forcing yourself to drive further than you feel comfortable to. If at all possible, try to bring a loved one along for the ride – not only will this mean you can drive in shifts, but having company is likely to work wonders for your mental health too.



In a similar vein, being overly stressed can affect how attentive you are. This can be for one of two reasons: either you become exhausted from being chronically stressed, or your body goes into a state of sleepiness to recover after a particularly stressful event. Especially if you start to feel tired before you drive, this can be a key indicator that your body needs you to rest; if you push on regardless, your biological override may kick in and try to force you to stop and take a break. Unfortunately, biology doesn’t take into account being in control of a moving car.
Ideally, if you need to rest as a result of acute stress, you should do so. But if you can’t, then make sure to take regular breaks and be more cautious than usual. When we’re stressed, it often means our decision-making gets focused on getting to our destination or goal as soon as possible – but doing so can put you at risk.


Lack of routine

As we discussed at the start, having an embedded sleep schedule can make it hard to drive when you would usually be in bed. But equally, not having a schedule can make it difficult for your body to understand if now is a good time to rest or not. A consistent sleep schedule is crucial for safe driving, as it helps the body understand when to rest. However, this can pose challenges if someone needs to drive during their usual sleep hours. Conversely, not having a regular sleep schedule can confuse the body about the appropriate times to rest, making safe driving difficult and leading to fatigue if they end up driving at times when they should be sleeping.
Research shows that people who have less than five hours of sleep are twice as likely to have a crash. If you’re regularly just going to sleep when you feel like it, you could be making it harder for yourself to operate at optimum safety behind the wheel. So, make sure you make a proper routine a priority, especially in the days leading up to a long drive.
We all have a responsibility to be safe on the road, and keep others safe too. By being aware of how you’re feeling and planning your trip accordingly, you can avoid making poor decisions or falling asleep at the wheel.


Special thanks to author: 
Wayne Thomas
Consultant | Researcher
Digital Content & Media
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