An Australian study has shown that long distance drivers who drink caffeinated beverages, like coffee or energy drinks, are at a decreased risk of getting into vehicle accidents compared to those who don’t. And the difference isn’t small. Drivers hopped up on caffeine have a 63% reduced chance of crashing.
The new study, which now appears in the British Medical Journal, was conducted by Mark Stevenson, Lisa Sharwood, and their colleagues at the George Institute for Global Health in Sydney.
Prior to launching the project, the researchers looked at pre-existing studies showing the positive effects of caffeine, including its ability to increase alertness and prevent injury in shift workers, and improve the capacity for task performance. And indeed, as one of the most popular stimulants in the world, much is known about caffeine’s ability to suppress sleep and activate arousal. At the same time, however, caffeine is notorious for its deleterious effects, like disrupting sleep and negatively affecting mood.
Lesser known is caffeine’s influence on drivers and its ability to help them stay alert and focused, particularly when driving for long stretches at a time. And indeed, long distance drivers like truckers have no choice but to sit for monotonously long periods in sedentary positions. And just as bad, their sleep cycles and circadian rhythms are often completely messed up.
Looking to learn more, Sharwood and Stevenson set up a study to explore the use of caffeinated drinks among a large sample group of long distance drivers. They wanted to determine the effect, if any, this legal stimulant might have on the frequency of auto accidents.
So, from December 2008 to May 2011, the researchers conducted a case-control study of long distance drivers in the Australian states of New South Wales and Western Australia. Each participant had to drive a truck no less than 12 tonnes in weight, and traverse a distance of at least 200 km (124 miles). The participants included 530 long distance drivers of commercial vehicles who were recently involved in a crash attended by police (cases) and 517 control drivers who had not crashed while driving a commercial vehicle in the past year. Interestingly, almost all of the drivers recruited were men (99%), and a disproportionate number overweight or obese (comes with the territory, I guess).
Around four in ten of the drivers (43%) used coffee, tea, caffeine tablets, and energy drinks in a conscious effort to stay alert. The researchers tracked their consumption habits, including the amount of caffeine contained in each beverage or tablet. To simplify things, the researchers converted individual responses into three levels of consumption: “low,” “moderate,” and “high” (low = 200 mg a day, moderate = 200 to 400 mg a day, and high caffeine = more than 400 mg a day).
In addition, the scientists tracked the number of kilometers driven, night driving schedules, sleep patterns, and breaks taken. They also considered factors like alcohol consumption, the use of illegal stimulants, and levels of exercise.
After accounting for all the various factors involved, the resulting data showed that drivers who consumed caffeinated substances for this purpose had a 63% reduced likelihood of crashing compared to drivers who did not take caffeinated substances. The researchers concluded that, in a large population of long distance commercial vehicle drivers, the consumption of caffeine for the purposes of staying awake while driving can significantly protect against crashing.
The study concludes with this recommendation:
While comprehensive fatigue management strategies for these drivers should consider the provision for adequate breaks and sufficient sleep and the promotion of regular exercise, the use and influence of caffeinated stimulants should be considered as an effective adjunct strategy to maintain alertness while driving.
The researchers caution, however, that the stimulant effects of caffeine only lasts for a short period of time and should never be used as a substitute for proper sleep.
Read the entire study at the British Journal of Medicine.
