Bacteria reveal our eating habits

SMALL PRINT:ARE YOU a committed carnivore? Or do you tend to load your plate with plant carbs?

Well, your long-term dietary patterns may be linked to the types of bacteria found in your gut, according to a new US study.

The researchers, from the University of Pennsylvania, looked at the recent and long-term diets of 98 healthy volunteers, and they analysed bacterial DNA in faecal samples to get an insight into the types of bugs that were living in their guts.

From the DNA data they could classify individuals into groups of microbial “enterotypes” based on the make-up of the gut flora.

And what they found was that the Bacteroides and Prevotella gut enterotypes broadly lined up with either a typical Western diet rich in meat and fat versus a diet rich in plant material.

“Enterotypes were strongly associated with long-term diets, particularly protein and animal fat (Bacteroides) versus carbohydrates (Prevotella),” write the study authors in Science this month.

But what happens if you alter your diet? The researchers tracked changes as 10 participants (all Bacteroides) ate different grub, and found differences in the microbiome even within 24 hours, but the general enterotype remained stable even over 10 days, suggesting that enterotypes are linked with diet in the longer term.

The research will now study what happens to the microbial composition of the gut when people with Crohn’s disease change their diet, according to a release from the University of Pennsylvania.

“Crohn’s disease is caused in part by the way our body responds to the microbes in our intestines,” explains researcher James Lewis. “Dietary therapies are different from most other Crohn’s disease therapies because the dietary therapies don’t suppress the immune system. One hypothesis is that these dietary therapies work by changing what organisms live in the intestines.”