Researchers at the University of East London had 88 volunteers ages 18-47, who say they love coffee and drink at least two cups every day, tested for mental performance, reaction times and mood, The Daily Telegraph reports.
Caffeine is a stimulant and combats drowsiness and fatigue.
Those who were told they were given coffee with caffeine -- but in reality drank decaffeinated coffee -- reported noticing a significant improvement in performance and mood and some did better than those who drank coffee with caffeine, the researchers say.
The finding are published in the journal Appetite.
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