A high proportion of Prevotella bacteria in relation to Bacteroides bacteria was associated with more weight loss on a diet high in fruit, vegetables, fiber and whole grains. People with a high proportion of Bacteroides in relation to Prevotella bacteria did not seem to have a weight loss benefit when changing to this type of diet.

This study adds to the larger body of evidence that demonstrates that intestinal bacteria play an important role in metabolism and predict metabolic response to various food types.