Those are some excellent questions. Here is my own information, from my own research and experience:
I have been using Miracle-Mineral-Supplement /sodium chlorite on and off for 4 years, and I am aware of many hundreds of others who have done likewise. I have never had a problem with my own organs being attacked or destroyed by it, and I have also found that my beneficial flora actually proliferate when I am combining the Miracle-Mineral-Supplement protocol with a greener style of eating.
MMS goes after organisms that are BOTH acidic and anaerobic. So, beneficial flora, which may be acidic but are always aerobic (oxygen metabolizing), do not fill both criteria. Likewise for our own body cells and tissues, which are aerobic.
If Miracle-Mineral-Supplement , which can be considered almost explosive in the way it oxidizes stuff that meets both conditions, directly oxidized our living, healthy cells then it would start right in the mouth and we would feel it immediately.
Please be assured that in my own 4 years experience, and in the experience of the hundreds of others I know who have used it, there has never been a case of harm to our own body tissues from low-dose MMS. Also, this is backed up by Humble's own experiences with the 70,000 plus people he has treated.
MMS does exactly what he says it does, but it absolutely MUST be combined with diet and lifestyle changes to achieve optimal health.
The combination of these two factors (acidity and anaerobic metabolism) is the key to understanding the selective cleansing that goes on with MMS.