Not once did the study mention fungus in the gut. Doug Kaufmann at www.knowthecause.com says that yeast causes obesity. So, if this is true, than bacteria has nothing to do with it, except for the fact that good bacteria in the gut keeps yeast from overgrowing. Antibiotics are fungal metabolites (fungal toxins). It makes sense that thin people would have more pre and probiotics in their gut to keep fungus in check! Very interesting!

Sally B.