Although the center of the bowel contents is often unaffected by electric current, sometimes it is nearly all sterilized by zapping. There is no way of distinguishing between “good” and “bad” bacteria. However even good bacteria are bad if they come through the intestinal wall, so zapping targets mostly “bad”. bacteria. The good news is that perfect bowel habits often result in a few days. Evidently the good bacteria are benefited by killing the invasive ones. (Cure of all Diseases book)