Caffeine can’t counteract long-term sleep loss?

Can caffeine counteract long-term sleep loss?

Caffeine is widely used to increase alertness. Besides regular use (e.g. drinking coffee every day), caffeine is also used to counteract a lack of sleep.

Caffeine can reduce some of the negative effect of acute sleep loss, such as a decreased reaction time and alertness.  So can regular coffee intake compensate for poor sleeping habits?

This study investigated the effect of caffeine (400 mg/day) on reaction speed performance (psychomotor vigilance test; PVT) during 5 nights of sleep restriction (5 h time in bed). All subjects were submitted to a testing facility during the full study period and were tested every hour.

Caffeine partly counteracted the decline in reaction speed during the first 3 nights of sleep restriction compared to the placebo. However, from the fourth day onwards, there was no difference between caffeine and the placebo. 

These data suggest that caffeine is an effective tool to compensate for 1-3 nights of poor sleep. In contrast, caffeine is not a solution for a more chronic lack of sleep.

Study:
Doty TJ et al., Limited Efficacy of Caffeine and Recovery Costs During and Following 5 Days of Chronic Sleep Restriction. Sleep. 2017

Go to the next infographic in the sleep series:
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