When the clocks change many drivers start and complete their full working day in the dark. The lack of daylight hours can result in increased fatigue and susceptibility to Seasonal Affective Disorder (SAD).
A 2019 survey by Mercedes-Benz Vans revealed the impact Seasonal Affective Disorder (SAD) has on the van community, with 30% of drivers surveyed admitting to suffering from SAD, which can lead to depression, lethargy and reduced concentration. 45% of drivers confessed that shorter days affect their mood and reported typical symptoms of SAD, including tiredness, loss of concentration and early signs of mental health issues. 83% of van drivers said that tiredness affects them more during autumn/winter.
What causes SAD?
The causes of SAD aren’t completely clear, but the main theory is that a lack of sunlight stops a part of the brain called the hypothalamus working properly, which may affect the:
- production of melatonin – melatonin is a hormone that makes you feel sleepy; in people with SAD, the body may produce it in higher than normal levels
- production of serotonin – serotonin is a hormone that affects your mood, appetite and sleep; a lack of sunlight may lead to lower serotonin levels, which is linked to feelings of depression
- body's internal clock (circadian rhythm) – your body uses sunlight to time various important functions, such as when you wake up, so lower light levels during the winter may disrupt your body clock and lead to symptoms of SAD
It's also possible that some people are more vulnerable to SAD as a result of their genes, as some cases appear to run in families.
Ignoring SAD and its effects among those who drive for work, or for long periods, increases the risk of accidents on the roads, endangering the driver and other road users. A separate study by Insurethebox discovered that during the autumn and winter months, accidents between 5pm-8pm increase by 36%.
Symptoms of SAD can include:
- a persistent low mood
- a loss of pleasure or interest in normal everyday activities
- feelings of despair, guilt and worthlessness
- feeling lethargic (lacking in energy) and sleepy during the day
- sleeping for longer than normal and finding it hard to get up in the morning
- craving carbohydrates and gaining weight
The main treatments for SAD are:
- lifestyle measures – including getting as much natural sunlight as possible, exercising regularly and managing stress levels
- light therapy – using a light box, designed to combat SAD, for 30 minutes in the morning to simulate exposure to sunlight
- talking therapies – such as cognitive behavioural therapy (CBT) or counselling
- antidepressant medicine – such as selective serotonin reuptake inhibitors (SSRIs)
How to combat tiredness at the wheel
The Highway Code UK warn that highway hypnosis can set in before you’re even aware it’s happening. Signs that you are too tired to drive include burning eyes, heavy eyelids, daydreaming, not remembering driving the past few miles, yawning a lot, and drifting out of your lane.
Drinking caffeinated coffee and rolling down the window can act as a short-term fix. Fresh air, especially when it’s cold, can snap you out of your daydreaming when you’re behind the wheel.
Playing music, having a conversation with someone on a hands-free phone, and taking a quick pit stop to walk around your vehicle at a service station can also help.
The National Sleep Foundation claims that taking more regular breaks, and even napping for 15-45 minutes is the best way to prevent tiredness at the wheel.