Diets high in fiber associated with less antibiotic resistan
In this study, the researchers were looking for specific associations of the levels of antibiotic resistance genes in the microbes of the human gut with both fiber and animal protein in adult diets.

The researchers found regularly eating a diet with higher levels of fiber and lower levels of protein, especially from beef and pork, was significantly correlated with lower levels of antimicrobial resistance genes (ARG) among their gut microbes. Those with the lowest levels of ARG in their gut microbiomes also had a greater abundance of strict anaerobic microbes, which are bacteria that do not thrive when oxygen is present and are a hallmark of a healthy gut with low inflammation. Bacterial species in the family Clostridiaceae were the most numerous anaerobes found.

But the amount of animal protein in the diet was not a top predictor of high levels of ARG. The strongest evidence was for the association of higher amounts of soluble fiber in the diet with lower levels of ARGs.

Surprisingly, the most important predictor of low levels of ARG, even more than fiber, was the diversity of the diet. This suggests that we may want to eat from diverse sources of foods that tend to be higher in soluble fiber for maximum benefit.