Researchers report, on the job bleary-eyed shift workers seemed to make fewer mistakes after consuming caffeine, such as, a cup of coffee or a caffeinated energy drink.

The body’s natural clock or circadian rhythm is sometimes disrupted due to shift and night-time work, leading to shift-work disorder, which is a sleep disorder exhibiting symptoms of insomnia or excessive sleepiness related to work schedules. Workers can feel extremely drowsy at work due to the lack of quality sleep.

According to the National Sleep Foundation, around 14% of Americans work shifts, such as, nurses, truck drivers, and emergency personnel, who usually work off-hour shifts. Medical errors, automobile accidents and occupational injuries have been linked to sleepiness on the job.

Researchers from the London School of Hygiene & Tropical Medicine reviewed data from 13 studies regarding the effects of caffeine on the performance of shift workers, whose participants were aged 18 to 65, with most between the ages of 20 and 30 years,

Depending on the study, the workers received caffeine via coffee, energy drinks, food, or pills. In most studies, the workers completed neuropsychological tests for gauging their memory, attention, reasoning, and perception skills.

The study findings reveal caffeine helped shift workers improve their cognitive performance and reduced job-related errors, compared to doing nothing at all. However, none of the studies reviewed or assessed the effects of caffeine on work-related injuries.

It seems reasonable to assume reduced errors are associated with fewer injuries, although such a reduction cannot be quantified.