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Coffee drinking habits can significantly affect the composition of the gut microbiome
Last reviewed: 02.07.2025
An international team of medical researchers has found that people who regularly drink coffee have significantly higher levels of one type of gut bacteria than those who don’t. The study, published in the journal Nature Microbiology, involved analyzing stool and blood samples from a large number of patients, as well as examining similar data from large medical databases, to find out how coffee consumption affects the gut microbiome.
Nathan McNulty and Jeffrey Gordon of the University of Washington School of Medicine published a News & Views article in the same issue of the journal discussing the study in detail.
Background of the study
Previous research has shown that foods and drinks influence the gut microbiome — the community of fungi, yeast, and bacteria that live in the human gastrointestinal tract. However, it’s still not clear which foods promote a healthy microbiome and which ones have a negative impact.
In the new study, the team focused on the impact of one product, in this case a drink, on the microbiome. They chose coffee for two reasons:
- Coffee is consumed by a huge number of people.
- People either drink it daily or don't drink it at all, which allows for a clear division of the groups.
Progress of the study
The researchers examined medical data:
- 22,800 people from the UK and the US,
- 54,200 people from 211 cohorts.
This allowed us to compare gut microbiome composition data from stool samples between coffee drinkers and non-coffee drinkers to identify differences.
Main result
The study found a key difference between the two groups: coffee drinkers had eight times higher levels of the bacteria Lawsonibacter asaccharolyticus than non-coffee drinkers. These differences remained consistent across people around the world.
Possible consequences
At this point, the researchers don't know exactly how elevated levels of L. asaccharolyticus affect the human body. However, they speculate that the bacteria may be linked to the health benefits traditionally attributed to coffee consumption.
The researchers highlight that simply consuming a particular beverage or food can have a significant impact on the gut microbiome. This finding highlights the need for further research to understand which bacteria are associated with the beneficial effects and how the microbiome can be harnessed to improve human health.