Coffee consumption shown to boost gut microbiome and brain function, study reports

Researchers at Cork University in Ireland examined the effects of both caffeinated and decaffeinated coffee on the gut‑brain axis. Participants who drank coffee showed a significant increase in beneficial gut bacteria, especially Eggerthella sp. and Cryptobacterium curtum, which are thought to help clear harmful microbes and protect against stomach infections.

The study also found that decaffeinated coffee users experienced improvements in learning and memory, which the researchers attribute to the high polyphenol content of coffee. In contrast, those drinking caffeinated coffee reported lower anxiety levels and better attention and focus. Lead author Prof. John Cryan emphasized that coffee’s effects are complex, noting, “Regular coffee drinkers showed increased impulsivity and emotional reactivity, so moderation is key.” The findings suggest that coffee’s health benefits extend beyond caffeine, involving its antioxidant compounds and interactions with the microbiome.