A new study by researchers in Portugal and Spain suggests that drinking coffee may boost alertness beyond what can be attributed to caffeine alone, indicating that other factors such as the ritual of consumption and the beverage's sensory attributes may also play significant roles.
Researchers at the University of Minho's School of Medicine used MRI scans to monitor the brain activity of 83 habitual coffee drinkers. The participants, split into two groups, either consumed their regular morning coffee or caffeine diluted in hot water.
The study's findings, published in the journal Frontiers in Behavioral Neuroscience, showed that both caffeine and coffee led to decreased activity in areas of the brain associated with a resting state, pointing to an increased readiness to engage with daily activities.
However, coffee drinkers exhibited increased brain activity in areas linked to attention, focus, and short-term memory — effects not seen in the study participants who consumed caffeine alone.
The researchers hypothesize that the sensory elements of coffee, such as sight, smell, and taste, could contribute to the increased alertness felt by coffee drinkers.
"Coffee aficionados often see their morning cup as more than just a source of caffeine. It's part of a ritual that helps them feel ready for the day," Nuno Sousa, a professor at the University of Minho and one of the authors of the study, told NBC News.
The study does not seek to influence coffee consumption habits but rather explore why coffee might have effects on alertness and focus beyond its caffeine content, Sousa clarified.
Other researchers told NBC that the findings were expected because individuals tend to form associations with sensory experiences over time.
Mark Mattson, adjunct professor of neuroscience at Johns Hopkins University School of Medicine, and Dr. Uma Naidoo, a nutritional psychiatrist at Harvard Medical School, both pointed out that the sight, smell, and taste of coffee could activate brain regions associated with these perceptions, triggering feelings of alertness and readiness, according to the NBC report.
The researchers also noted the study's limitations, such as the potential impact of caffeine's blood flow restricting properties on the MRI scan results and the lack of inclusion of decaf coffee drinkers. Sex-based differences in response to coffee were also flagged, as the majority of the participants were women.
Despite these limitations, one consensus emerged among the researchers contacted by NBC: coffee is a healthier caffeine source than energy drinks or soda, given its richness in antioxidants, polyphenols, and a substance called trigonelline, known for its antibacterial, antiviral properties, and contribution to coffee's unique aroma and taste.