Can coffee actually reduce anxiety? A surprising new study says yes

May 05, 2026

There’s never been a better excuse to go for that third cup.

Coffee is such a fundamental part of so many people’s everyday existence, it’s almost impossible for them to imagine living without it. However, even the most ardent coffee lover (*waves frantically*) would likely laugh if you told them that coffee could reduce stress and anxiety. Yet that’s exactly what a new study out of Ireland has found.

Researchers at APC Microbiome Ireland at University College Cork have revealed that coffee doesn’t just give you a boost of energy when you need it – it actually rewires your mind, helping to reduce stress and improve your mood. It does this through what’s known as the gut-brain axis, which is the two-way communication between the gut microbiome and the brain.

Coffee and mood: what the study found

The researchers studied a group of regular coffee drinkers who had abstained from coffee for two weeks (the horror). They were then reintroduced to coffee, given either regular coffee or decaf. Samples were taken from both study groups during the period of abstinence and the period of reintroduction, which measured levels of bacteria in the gut. Participants also underwent regular psychological assessments.

Upon being reintroduced to coffee, both groups reported lower stress and depression levels and less impulsivity, which suggests that drinking coffee lowers stress and boosts mood, regardless of caffeine content. Levels of beneficial gut bacteria also increased in both groups.

Further, the decaf drinkers demonstrated a ‘notable improvement’ in learning and memory. The researchers suggest that these cognitive benefits may be due to the polyphenols in coffee. Meanwhile, those who drank caffeinated coffee reported reduced feelings of anxiety, as well as improved vigilance and attention. Caffeine was also linked to a reduced risk of inflammation.

takeaway coffee — That daily habit could be doing your health a big favour.

Coffee and gut health: long-term benefits

One of the study authors, Professor John Cryan, says that while the relationship between gut health and mental health is increasingly being better understood, the mechanisms behind coffee’s effects on the gut-brain axis had previously remained unclear.

“Our findings reveal the microbiome and neurological responses to coffee, as well as their potential long-term benefits for a healthier microbiome,” he says.

“Coffee is more than just caffeine – it’s a complex dietary factor that interacts with our gut microbes, our metabolism and even our emotional wellbeing. Our findings suggest that coffee, whether caffeinated or decaffeinated, can influence health in distinct but complementary ways.”