Man upset after getting into car accident

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LISBON, Portugal — Motorists whose diets are loaded with sugar, processed meats, and junk food are more likely to be involved in a car accident, according to new research. Scientists say snacking on burgers, sausage rolls, and biscuits – or guzzling soft drinks — is linked to riskier behavior behind the wheel, too. 

Two years ago a study of almost 400 lorry drivers in China found those who ate plenty of fried foods – such as the traditional trucker’s breakfast – drove worse behind the wheel. They concluded that junk food diets and unhealthy snacks contribute to fatigue – which can lead to dangerous driving. This latest study of 817 Estonians adds to evidence that what you eat can predict how safely you drive. Higher accident and driving conviction rates were identified among those with poor diets.

“We were able to pick out lots of associations between everyday risk-taking and risky driving,” says lead author Tonis Tokko, a Ph.D. student at the University of Tartu in Estonia, in a statement. “For example, we found subjects who drink energy drinks at least once a week were twice as likely to speed as those who didn’t consume them as often. We think it may be related to a need for excitement, rather than the drinks themselves being a direct cause of traffic violations. The drivers’ underlying psychological makeup may lead them both to speed, and to want to consume more energy drinks or junk food.”

They completed a series of questionnaires to measure impulsivity and aggression. Blood samples were also taken for genetic analysis. Police and insurance database records showed 137 participants who had been cautioned for speeding tended to have faster reaction times. However, they but also scored higher on physical and verbal hostility, undertook more strenuous exercise, and ate more junk foods – including energy drinks.

“Similarly, our psychological tests showed those with fast decision-making skills were 11% more likely to speed, and those with higher excitement seeking were 13% more likely to speed,” says Tokko.

Sugar high can lower overall sharpness

The increase in calories isn’t the only problem to consider when eating on the road. High sugar and fat content may briefly increase alertness, but it can cause a reduction in concentration levels and mood. Furthermore, drivers can be charged with careless driving if they cause a car accident while eating. 

The researchers have now found a psychological connection between eating junk food and driving convictions or car accidents. It is associated with a gene that metabolizes serotonin – a brain chemical targeted by antidepressants.

“Driving history is an excellent platform to study behavioral regulation. Most people drive, and driving convictions or accidents are objective records – they remain in databases. We found significant associations exist between risky traffic behavior and a range of lifestyle behaviors, such as undertaking strenuous exercise, alcohol consumption – or junk food and energy drink consumption,” explains Tokko.

His study shows that mutations that carry the neurotransmitter serotonin are associated with risky driving. “We found certain gene variants are associated with risk-taking behavior while driving and in other areas of life. But this is an early finding and still needs to be confirmed,” adds Tokko.

Lower risk of car accidents just another benefit of healthy eating

The Estonian Psychobiological Study of Traffic Behavior, which began in 2001, is the first of its kind.

“We are able to follow various driving-related factors over a period of years, including psychological behavior, blood tests to understand biological changes, and genetics,” says Tokko. “We also have a firm idea of which of these drivers have committed traffic violations or have been in accidents. We believe this to be a unique system. This study shows people who are reckless in traffic also tend to take chances in other areas of life. Our research shows there may be a biological tendency to this behavior.”

Adds Dr. Oliver Grimm, a psychiatrist at the University Clinic Frankfurt, who was not involved in the research: “This study is very interesting, as it is already known from large registry studies that ADHD and traffic accidents are more common in adults. This specific study from Estonia now helps to better understand how this accident-prone group is constituted from both the genetic risk and personality traits.”

It was presented at a meeting of the European College of Neuropsychopharmacology in Lisbon.

South West News Service writer Mark Waghorn contributed to this report.

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