People!
What a terrible argumentative discussion?
The rules of fasting other ibadah etc. are all very very simple.
If you are too sick/week to do ibadah, then don't follow the regular style of that ibadah.
If someone is sick, they don't have to fast (period).
It is insane to argue over insulin injection going to a cell or directly to your stomach.
Listen to PCG. She has a good real-life case.