After antibiotics, the Mediterranean diet helps the intestinal microbiome

What we eat can also make a difference in the recovery capacity of our intestinal microbiota after a course of antibiotics. This is what a new study published in Nature suggests, according to which a Mediterranean diet would help the natural and rapid restoration of useful intestinal bacteria. The studies were conducted on mice, but they contribute to expanding knowledge about diet and intestinal microbiota.

Diets and microbiota

Although the enthusiasm for microbiota testing is exaggerated today, there are several studies that are highlighting the importance that this large quantity and variety of bacteria (especially, but not only) has on our health. Just as there is a lot of research on diets and microbiota. For example, ultra-processed foods and in general a diet very rich in fat and low in fiber seem to have a negative impact on bacterial diversity and increase the risk of developing some metabolic diseases, the authors recall. On the contrary, a Mediterranean-like diet seems to have, among the many benefits, also a positive impact on the composition of our microbiota. Especially, as today's research shows, after taking antibiotics, which do not only affect pathogenic bacteria but also the "good" bacteria in our digestive system.

Mediterranean and “Western” in comparison

The authors of the new study fed a group of mice a diet more or less similar to the Mediterranean diet, that is, rich in plant fiber and low in fat, while they fed a second group what they call a “Western diet,” that is, an unhealthy diet, rich in fat and low in fiber. They then observed the recovery capacity of their microbiota after taking antibiotics.

During the study, the researchers also tested the effects of fecal transplantation, which aims to support the restoration of the microbiota by transferring intestinal bacteria from a healthy individual to one with damaged bacterial flora (in clinical practice it is used today mainly for the treatment of Clostridium difficile infections).

This is how the bacterial flora is reborn

By analyzing the composition of the intestinal microbiota of mice subjected to the two different diets and the fecal transplant, the research team observed that only those who had been given a Mediterranean-like diet experienced regular recovery of the intestinal flora after taking antibiotics. "This is not because the Western diet does not provide nutrients to the right microbes at the right time,"explained Eugene Chang of the University of Chicago, coordinator of the research. "You end up with a few species that monopolize these resources and do not create the conditions for other organisms necessary for recovery."

Doubts about fecal transplant

The other animals were more susceptible to infection with Salmonella bacteria, and fecal transplantation did not appear to be effective in restoring the adequate quantity and variety of intestinal bacteria. “Our data challenge the widespread enthusiasm for fecal microbiota transplantation (FMT) as a strategy to address dysbiosis and demonstrate that specific dietary interventions are, at the very least, an essential prerequisite for effective fecal transplantation and may represent a safer, more natural and less invasive alternative,” the authors conclude.