Study links coffee consumption to specific gut bacterium; researchers find Lawsonibacter asaccharolyticus six to eight times more abundant in regular coffee drinkers

The goal is ambitious: to understand how individual foods interact with the microbiome and with what effects. But the findings of a research conducted by the Department of Cellular, Computational and Integrative Biology – Cibio of the University of Trento try to provide a piece of the puzzle. 
Specifically, the researchers focused on coffee, a beverage that so many people love and drink on a regular basis. The study found, with a 95% accuracy rate, that the microbiome tells whether someone drinks coffee or not, thanks to a bacterium called Lawsonibacter asaccharolyticus. What is interesting about this study is its potential to identify and analyze the impact of individual foods on specific gut bacteria.
About the study . The first author of the paper is Paolo Manghi, researcher at the Cibio Department of the University of Trento, but other scientists from the Cibio Department and Harvard University contributed to the work, as well as several European and US research institutions. The group was coordinated by Nicola Segata, professor of Genetics and head of the Computational metagenomics laboratory of the Cibio Department.
The researchers examined data from over 22,000 individuals, and established a clear relationship between coffee consumption and the gut microbiome thanks to the presence of the bacterium Lawsonibacter asaccharolyticus, which is on average six to eight times more abundant in individuals who regularly drink coffee than in those who don't.
This aspect has been confirmed in the laboratory. "Growing this bacterium in vitro – explains Paolo Manghi – we have seen that it grows faster if you add coffee to the culture medium".
But there's more to it. As further evidence of this association, the same bacterium has been detected in greater amounts in individuals who consume high doses of coffee than in those who consume it more moderately. And these same associations were found using information from 25 countries around the world. In populations that drink a lot of coffee, this bacterium is almost always present. Interestingly, the European countries that drink the most coffee are Luxembourg, Denmark and Sweden. On the other hand, and broadening the horizon of the study, Lawsonibacter asaccharolyticus is almost completely absent in China, Argentina and India.
It is not known whether this bacterium has a positive or negative impact on people's health. "It does not seem to play a particularly important role," says Nicola Segata. "We have seen – he adds – that if we drink coffee, we very strongly stimulate the presence and abundance of this bacterium, otherwise we do not. This can be important for other bacteria and foods that have more important health effects. In fact, we have data on which gut bacteria have potentially beneficial effects and now we will focus on understanding which specific foods stimulate their growth."
Future perspectives . The authors of the study would like to continue the research by analyzing other foods. A difficult challenge. Because those who drink coffee can say how many coffees, they have every day with a good level of accuracy. But it may be more difficult to explain, for example, how often you have broccoli and how you prepare it – and broccoli may have a more positive impact than coffee from the point of view of the bacteria it stimulates.
In the future, the researchers believe, a microbiome test could reveal the presence of absence of a bacterium associated with a certain food, and design a personalized diet.