When I saw you are eating only arrowroot I remembered people having digestive problems with foods containing chicory root. Chicory has a high level of inulin which is what triggers digestive upset for many people. I haven’t done that level of research on arrowroot, but the following came up in a quick search on arrowroot:
“Non-digestible carbohydrates such as inulin and oligofructose (OF), including their intestinal fermentation products, may modulate the gut-associated lymphoid tissue (GALT) as well as the systemic immune system. Inulin and OF are classified as prebiotics which occur naturally as plant storage carbohydrates in vegetables, cereals, and fruits”.
Did your medical team recommend a diet heavy in arrowroot? If not, what would they say?