Truck drivers in Georgia and across the U.S. often drink caffeinated beverages to stay awake behind the wheel, but a new study suggests that high caffeine consumption over the long term may do more harm than good.

A transport safety expert from the Loughborough University Design School and researchers at the Virginia Tech Transportation Institute focused on two groups of truck drivers: those who drink one cup of coffee a day, and those who drink over five cups. A total of 3,007 truck drivers participated. Asked if they had ever been in an accident in the past three years, 21.6% of the low coffee drinkers said yes whereas 27.8% of the second group said yes.

Not only that, but the high coffee drinkers also reported having poor health. Many failed to get restful sleep or follow a proper diet, and others reported that they smoke or drink excessively. Though the study relied on self-reported data, this data can be trusted since participants were told that their answers would not be shared with their employer.

It was a unique study in that it did not, like previous ones, analyze the effects of caffeine in a laboratory setting. However, further studies will be needed to show that the relationship between high coffee consumption and high crash risk is, indeed, a cause and effect relationship.

Those who are harmed in motor vehicle accidents due to the negligence of another motorist often suffer injuries that require extensive and costly medical care and treatment, and in some cases they are unable to return to work during the recovery period. They might want to have a lawyer’s help when seeking compensation for their losses.