The enterotypes were strongly associated with diet, particularly protein and animal fat (Bacteroides genus) versus carbohydrates (Prevotella genus). Both Bacteroides and Prevotella are broad genera of bacteria species that typically live in the human gut. Humans tend to have mostly a species from one bacterial group but not both. Vegetarians were more likely to be in the Prevotella group, the enterotype associated with diets enriched in carbohydrates and lacking meat, and the one vegan was also in the Prevotella group.
Subsequently, 10 healthy volunteers were enrolled in a controlled feeding experiment in which their diets were fixed for a 10-day period. All ten subjects in the controlled-feeding experiment were in the Bacteroides group at the start, during, and at the end of the experiment. Their gut microbiomes changed within one day but stayed within the same broad Bacteroides group, even if they ate a diet high in carbohydrates over the 10-day period, emphasizing the short-term stability of the enterotypes.
There are several potential applications of this research. The Penn investigators are currently exploring the relationship between dietary therapies for Crohn's and the composition of the gut microbiome.
"Crohn's disease is caused in part by the way our body responds to the microbes in our intestines," explains 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."'/>"/>
|Contact: Karen Kreeger|
University of Pennsylvania School of Medicine