Coffee Rewires the Gut-Brain Link, Boosting Mood and Memory, Study Finds

A Nature Communications-backed study from APC Microbiome Ireland (University College Cork) shows habitual coffee consumption reshapes the gut microbiome and influences mood and cognitive function. Both caffeinated and decaffeinated coffee yielded benefits: decaf users showed improvements in learning and memory, likely due to polyphenols, while caffeinated coffee was linked to reduced anxiety and heightened alertness. In a 62-participant study (31 coffee drinkers vs. 31 non-drinkers) with a two-week coffee withdrawal followed by blinded reintroduction (half decaf, half caffeinated), researchers observed shifts in gut metabolites and the enrichment of bacteria such as Eggertella sp and Cryptobacterium curtum among coffee drinkers, suggesting a microbiota–gut–brain mechanism with potential long-term health implications.