The concept behind water being the cause of many diseases is that many diseases are caused by sheer dehydration. Our cells, tissues, and entire body is slowly getting dehydrated. Depending on which part of the body is de-hydrated, we get the specific disease.
Diabetes is caused by the pancreas inability to process insulin properly. Perhaps the alkaline Ionized Water is reversing diabetes by hydrating the pancreas and providing it with the much needed water and alkaline minerals.
All this is my hypothesis from all the testimonials I have read about Ionized Alkaline water. But it would be nice if some diabetic out here tries this water for a couple of months and reports back the results.