It is already known that a more diverse gut microbiota is linked to better general health. What you eat can boost microbial diversity, such as fruit, veggies, and whole grain foods. However, adding coffee, tea, dark chocolate, red wine, even beer, to your diet might also help boost your gut microbiota diversity and benefit your health, scientists suggest.

Largest studies to date

Two recent studies on the topic were published in the journal Science: one from Belgium and the other from the Netherlands. These gut microbiota studies include the largest number of healthy people examined to date.

Both studies concluded a person’s diet, lifestyle and medication intake have profound effects on the gut microbiota, which in turn could impact significantly on general health.

Findings

Researchers examined stool samples of more than 4,000 people and analyzed their gut microbiome. They mapped out some species of bacteria living inside the guts of the volunteers and linked the presence and abundance of some of those bacteria to the people’s diet and reported activities.

The first study is one of the largest population-wide studies on gut microbiota variation among healthy volunteers. Scientists identified 69 factors associated with gut microbiota composition.

Most of those factors were linked to diet. For instance, a diet rich in sugar is linked with the presence of bacteria that process simple carbohydrates but prevent other microbial species from growing. The more fiber in the diets of volunteers, from fruits, vegetables, legumes, and whole grain bread, the more diverse the gut microbiota was.

The researchers also saw a correlation between gut microbiota diversity and beer consumption, for reasons not yet clear.

This was also true for dark chocolate, but not milk chocolate. The researchers of this study suggested that some cocoa compounds more abundant in dark chocolate may account for its effect.

Drugs had been found to exert strong influence on gut microbiota: not only antibiotics as expected, but also laxatives, antihistamines, hormones and anti-inflammatory medications.

In the second study, the researchers similarly identified some beneficial food for gut microbiota diversity: in addition to fruits and vegetables, they found nuts, coffee, tea, and red wine favored the diversity of bacteria. In fact, 60 dietary factors were found to influence gut microbial diversity.