University of Warwick and Bielefeld University study reveals early-day caffeine boosts mood and emotional well-being

University of Warwick and Bielefeld University study reveals early-day caffeine boosts mood and emotional well-being

(IN BRIEF) A study by the University of Warwick and Bielefeld University has tracked more than two hundred young adults over four weeks, collecting 28,000 mood reports through daily smartphone prompts. The research, published in Nature Scientific Reports, shows that caffeine consumption in the first 2.5 hours of the day is linked to heightened enthusiasm, happiness, and reduced sadness, with effects consistent across individuals regardless of anxiety or depressive symptoms. While caffeine appears to provide a reliable emotional boost, the researchers caution against excessive use due to risks of dependency and sleep disruption.

(PRESS RELEASE) COVENTRY, 18-Aug-2025 — /EuropaWire/ — Researchers at the University of Warwick and Bielefeld University in Germany have explored how caffeine influences mood in young adults, tracking over two hundred participants for up to four weeks. Using smartphone prompts sent seven times daily, the study captured nearly 28,000 individual reports on caffeine intake and emotional state, offering one of the most detailed insights into daily mood fluctuations related to coffee and tea consumption.

The findings, published in Nature Scientific Reports, reveal that caffeine drinkers tend to feel happier and more enthusiastic during the first 2.5 hours of the day after consuming coffee or tea compared to later in the day. This early boost in mood was also associated with increases in contentment and decreases in sadness, though the researchers note it is unclear whether these improvements stem from caffeine’s neurochemical effects or the easing of mild withdrawal symptoms after sleep.

Professor Anu Realo, from the Department of Psychology at the University of Warwick, explained the mechanism behind these effects: “Caffeine blocks adenosine receptors in the brain, which increases dopamine activity in regions linked to alertness and positive emotions.” She added that even moderate caffeine drinkers may experience withdrawal symptoms overnight that are quickly alleviated by their first cup in the morning.

The research also examined whether individual differences in mental health or anxiety altered caffeine’s effects. Contrary to expectations, the team found no significant differences in mood responses between participants with varying levels of anxiety, depressive symptoms, or sleep problems. First author Justin Hachenberger of Bielefeld University said: “We were surprised to see such consistency in the emotional benefits of caffeine, regardless of prior mental health or habitual consumption levels.”

Despite these positive findings, the authors emphasized the importance of moderation. Senior author Professor Sakari Lemola from Bielefeld University cautioned that high caffeine intake can lead to dependency, disrupt sleep, and pose health risks. He noted: “Caffeine use is widespread, with about 80 per cent of adults globally consuming caffeinated beverages. Its use stretches back through human history—and even beyond, with evidence that bees and bumblebees prefer caffeinated nectar.”

The manuscript “The association of caffeine consumption with positive affect but not with negative affect changes across the day” is published in nature scientific report. DOI: 10.1038/s41598-025-14317-0

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SOURCE: University of Warwick