A new clinical study suggests that coffee does more than just boost alertness, it may significantly reshape the microbiota–gut–brain axis, influencing mood, cognition, and gut chemistry in ways that go beyond caffeine alone. Researchers found that regular coffee drinkers showed distinct changes in their gut microbiome, including increased levels of certain bacteria such as Cryptobacterium and Eggerthella. These shifts were linked to reduced levels of key neuroactive compounds like GABA and beneficial microbial metabolites such as indole-3-propionic acid, both associated with brain health and emotional regulation.
Interestingly, the behavioral outcomes mirrored these biological changes. Coffee drinkers exhibited higher impulsivity and emotional reactivity, while non-drinkers performed better in memory-related tasks. Notably, some of these effects were reversible, participants who stopped drinking coffee showed partial recovery in their gut metabolite profiles, while reintroducing coffee rapidly altered the microbiome again.
Perhaps most surprising, several of these effects occurred independently of caffeine, pointing toward other bioactive compounds in coffee, such as phenolic acids and theophylline, as key drivers.
