A diet rich in ultra-processed foods is strongly associated with dangerous driving, with more errors and infringements at the wheel.

Some vegetable burgers ready to be eaten.

A ‘junk food’ diet can increase the risk of dangerous driving among drivers by enhancing fatigue, which is often a key factor in vehicle collisions, suggests research published online in the journal Occupational & Environmental Medicine.

Few studies have looked at the potential impact of dietary patterns on the driving behaviors of professional truck and truck drivers.

To try to fill this data gap, the researchers evaluated whether dietary patterns, fatigue, and driving behavior could be related in a sample of 389 male truck drivers from a transport company in Suzhou, China. Most of the drivers were between 31 and 60 years old, between 6 and 10 years of experience and between 50,000 and 100,000 km of annual travel.

Each driver was asked to specify how much and how often they had eaten any of the 25 foods in the previous 12 months on a Food Frequency Questionnaire.

They also completed the Multidimensional Fatigue Inventory, which assesses physical and mental fatigue on a 5-point scale, as well as two validated questionnaires on driving behaviors and attitudes towards other drivers on the road.

Dietary patterns were classified as: rich in vegetables; staple foods (high carbohydrate intake, unrefined grains, dairy products, and eggs; animal proteins (fish and poultry); and snacks (fried foods, desserts, and sugary drinks).

The diets rich in vegetables and staples were strongly associated with safe driving behaviors. The Diet rich in animal protein was strongly associated with higher rates of errors, gaps in concentration, and minor traffic offenses., while the snack diet was strongly associated with unsafe driving behaviors.

The results indicated that fatigue likely mediated the impact of dietary patterns on driving behaviors: diets rich in vegetables and staple foods were associated with less fatigue, while animal protein and snack diets were associated with greater fatigue.

This is an observational study and as such cannot establish the cause, only the correlation. The study relied heavily on recall and self-report. And the researchers didn’t get any information on potentially important factors, such as smoking, physical activity, work shifts, and job stress.

However, they point out that Eating too many unhealthy snacks is often associated with erratic meal times and an altered metabolism, which could affect many tasks that require vigilance, alertness and concentration.

And they conclude: “The results of this study support a relationship between dietary patterns and driving behavior in a sample of professional truck drivers.”

“Furthermore, through the pathway analysis presented, it is possible to conclude that positive driving behavior can be predicted by prudent dietary patterns, such as diets rich in vegetables, while some dangerous behaviors behind the wheel (mistakes, lapses and infractions), can be predicted by unhealthy dietary patterns characterized by a high consumption of fats and sugars“.