Overview

• A study by Universität Bielefeld and the University of Warwick in Scientific Reports tracked 236 habitual caffeine consumers via seven daily mood surveys over four weeks.
• The analysis showed a marked increase in happiness and enthusiasm immediately following the first caffeinated drink of the morning compared with caffeine-free mornings.
• Caffeine intake also corresponded with slight reductions in negative emotions such as sadness and anger, though these effects lacked a clear time-of-day dependence.
• Authors propose that caffeine’s blockade of adenosine receptors boosts dopamine activity but caution that alleviation of overnight withdrawal symptoms may partly explain the results.
• The research excludes non-consumers and notes the risk of caffeine dependence, prompting calls for replication in diverse populations and designs to clarify causality.