Overview
- Regular caffeine consumers reported a marked increase in positive emotions such as happiness and enthusiasm within 90 minutes of intake
- Participants experienced a smaller reduction in negative feelings like sadness or upset that remained consistent throughout the day
- Mood enhancements appeared across all subgroups, regardless of habitual caffeine use, anxiety or depressive symptoms, and sleep quality
- Researchers attribute the effect to caffeine’s pharmacology—blocking adenosine receptors and boosting dopamine activity—while noting possible relief from overnight withdrawal
- Authors caution that high or late-day caffeine consumption can lead to dependence, health risks, and impaired sleep