Caffeine Really Does Help Truck Drivers Avoid Crashes, Study Finds

A study of Australian truck drivers has found that caffeine greatly reduced the number of car accidents caused by fatigue.

Some people skip caffeine because it causes them to “crash.” But for truck drivers, a new study suggests caffeine may be the secret to steering clear of a crash.

Truck drivers who typically consumed caffeine were far less likely than other drivers to be involved in traffic accidents, according to an Australian study in the British Medical Journal that controlled for lack of sleep and other factors.

Researchers at The George Institute, University of Sydney surveyed 530 long distance truck drivers who were involved in an accident from 2008 to 2011. An additional 517 drivers, who had not been involved in an accident over the previous year, were also surveyed to make up a control group.

Researchers used personal interviews to determine the drivers’ demographics, health behaviors and the amount of caffeine they typically consumed.

They found that most of the drivers involved in accidents (85 percent) didn’t regularly consume energy drinks and most (78 percent) didn’t regularly consume any caffeine. By contrast, just 51 percent of the control group drivers — those who weren’t involved in an accident — said they didn’t typically drink caffeine.

Overall, truck drivers who reported that they consumed caffeine were involved in just 116 of the 530 truck crashes.

“Our findings suggest that the consumption of caffeinated stimulant substances is associated with a significantly reduced risk of involvement in a crash for long distance drivers in Australia,” the study concluded. “The use and influence of caffeinated stimulants should be considered as an effective adjunct strategy to maintain alertness while driving.”

The control group of drivers, those not involved in an accident, were about as likely to consume low and moderate caffeine levels as drivers involved in the accidents. But 192 of the drivers not involved in accidents reported high caffeine consumption, compared to only 70 drivers involved in a crash.

Researchers defined low caffeine consumption as less than 200 milligrams a day (a little less than the amount contained in a typical energy drink), moderate consumption as 200 to 400 milligrams a day, and high consumption as more than 400 milligrams a day.

According to, driver fatigue causes an estimated 1,550 annual deaths in the United States, and 71,000 injuries. Federal statistics from 2012 claimed that more than 4 percent of surveyed drivers admitted to drowsy driving, but as high as 33 percent of fatal crashes could involve sleepy drivers.

Authors of the study hope that their results help improve fatigue management strategies for truck drivers.

While caffeine “may seem effective in enhancing their alertness…it should be considered carefully in the context of a safe and healthy fatigue management strategy,” said Lisa Sharwood, M.S., the study’s lead author, in a press release. “Energy drinks and coffee certainly don’t replace the need for sleep,” she added in the release.

By Jeffrey Kopman