A new study has found that shift workers who consume caffeine make fewer errors. Researchers say the findings of this study have implications for health workers and for any industry relying on shift or night work, such as transportation.
Approximately 1 in every 7 shift workers in industrialized nations is involved in some shift or night time work, which may affect natural circadian rhythms or ‘body clocks’. In shift work disorder (SWD) employees sleep only for limited periods and as a result can become very drowsy during working hours. Drowsiness is believed to raise the risk of hazards, such as traffic crashes, occupational injuries and medical errors.
The scientists reviewed data from 13 trials, examining the effects of caffeine on performance in shift workers, mostly in simulated work situations. Caffeine was given in coffee, pills, energy drinks or caffeinated food. In some trials, performance was assessed by tasks such as driving, whereas in others it was assessed by neuropsychological tests. Caffeine appeared to reduce errors compared to placebos or naps, and improve performance in various neuropsychological tests, including those focusing on memory, attention, perception and concept formation and reasoning.
Injuries were not measured directly in any of the trials. However, better performance probably results in fewer injuries caused by drowsiness, the researchers argue.
Lead researcher Katharine Ker of the London School of Tropical Medicine in London, UK, said “It seems reasonable to assume that reduced errors are associated with fewer injuries, although we cannot quantify such a reduction.”
Most of the trials looked at individuals aged between 20 and 30 years and therefore, because the effect of disruption to the circadian rhythm varies with age, there is still a need for more research on how caffeine alters alertness in workers in their late 30s, 40s, 50s and 60s.
The researchers say there should be further studies to examine the effects of caffeine compared to other measures in order to reduce mistakes made by shift workers.
Ker K, Edwards PJ, Felix LM, Blackhall K, Roberts I.
“Caffeine for the prevention of injuries and errors in shift workers”
Cochrane Database of Systematic Reviews 2010, Issue 5. Art. No.: CD008508.
Written by Christian Nordqvist