Drinking moderate amounts of coffee each day is associated with a number of health benefits. It turns out that the coffee is also feeding a particular strain of gut microbe - Lawsonibacter asaccharolyticus.
Researchers found that more people who drink coffee daily have Lawsonibacter asaccharolyticus in their gut microbiome (the community of microbes, bacteria, and viruses that live in the intestines) than people who don't drink coffee. Additionally, the more a person drinks coffee daily, the higher the levels of the bacteria.
Newborns and children rarely have this bacteria in their gut microbiome. The bacteria is mainly found in adults living in places with an urbanized Western-lifestyle. Further research showed that the coffee stimulates the growth of L. asaccharolyticus.
By the way, it appears to be a beneficial bacteria. And yes, many other studies find that what you eat (your daily diet) influences the composition of microbes living in the gut.
From Newsweek: What Coffee Does To Your Gut
Coffee drinking seems to alter which microorganisms live in our guts, with potentially far-reaching implications for health, a large study has found.
Everyone's gut microbiome is unique, with varying amounts of different types of microorganisms, and scientists believe it changes depending on our diets, environments and the guts of people in our lives.
Professor Dr. Tim Spector, scientific cofounder of ZOE and one of the study's authors, told Newsweek that the study's findings "further the idea that there's a specific link between the food we eat and the microbes in our gut—meaning we hold immense power to improve our health through the food choices we make.
"Coffee's health benefits are likely thanks to its complex chemical nature," said Spector. "Made by fermenting beans, coffee contains hundreds of compounds that are present in both caffeinated and decaf coffee. These include a range of polyphenols, which fuel the gut microbiome and can help reduce blood sugar and blood pressure."
The scientists conducted their research using data from 22,800 people in the U.S. and U.K., who submitted detailed dietary information, and public data from another 54,200 people in 211 other cohorts. They also analyzed more than 400 samples of plasma and more than 350 fecal samples, and conducted two in-vitro experiments, to investigate how coffee might impact a person's gut.
They found that one strain of bacteria, called Lawsonibacter asaccharolyticus, was strongly associated with coffee drinking. People who drank more than three cups of coffee per day had up to eightfold higher levels of this bacteria in their guts, compared to people who drank fewer than three cups of coffee per month.
Among people who drank coffee regularly, those who drank more coffee seemed to have more L. asaccharolyticus too—although there was more of a difference between coffee drinkers and nondrinkers.
The relationship was remarkably consistent across populations of people in 25 different countries, the scientists found—and, when they fed L. asaccharolyticus coffee in a test tube, the bacteria grew.