Intestinal parsites don't thrive on gut bacteria and, in fact, prefer the same food we eat -- the exact same food -- ours, in fact. They also, if they become too numerous, can sometimes begin to feed on the mucosa of our GI tract, which is even worse. But they don't actually go after the intestinal flora that normally occur, and are equally indifferent to unwanted bacteria. They just eat our food and sometimes a little bit of us as well.
Hope this answers your question. Good luck to you.,
John Kenyon, EMT, CCT
Non-invasive cardiology tech, Emergency and Critical Care technician, Critical Incident Stress Mgmt. specialist