🍬 Sugar could influence how antibiotics affect the gut microbiome

A diet high in sugar could make the gut microbiome more vulnerable during antibiotic treatment.

Antibiotics fight the bacteria responsible for an infection, but they also affect the many useful bacteria that live in our intestines and form the gut microbiome. After treatment, its composition can take time to return to a balance close to what it was before.

The researchers first focused on hospitalized patients receiving antibiotics. Those who consumed more foods high in sugar had a less diverse microbiome. Some bacteria, particularly from the Enterococcus genus, also became more abundant.

To isolate the effect of sugar more precisely, the researchers continued their experiments in mice. In animals treated with antibiotics, a diet enriched with sucrose intensified changes in the gut microbiome. After treatment stopped, the return to the initial state was slower.

Sugar would mainly alter the conditions in which gut bacteria compete for nutrients. After the antibiotic has passed through, some species become rare and leave more room for others.

Bacteria able to make rapid use of sugar can then gain an advantage. Enterococcus was among the groups favored in the experiments. The microbiome can therefore reorganize differently depending on the diet received at the same time as the treatment.

Diet could influence how the microbiome withstands antibiotics and then rebuilds itself. Controlled trials in humans will now have to determine whether reducing certain sugars during or after treatment can actually speed up this recovery.