Day 4 of 40 day water fast

So I'm currently on day 4 of a 40 day water fast. I started at 249lbs, 5'7", last night I decided to weigh in and I'm already down to 240lbs. I have multiple sclerosis, and have since 2009. I'm hoping to not only lose weight but also "reboot" my health before the neurologist sticks me on an extreme medication (Lemtrada, or Tysabri). I plan on going on to a ketogenic diet after the 40 days to help lose remaining weight. My goal is to get to 160lbs. I do have some questions though:

Should I be taking supplements during the fast?

Whats the best way to break the fast?

Best ways to prevent weight gain after the fast is over?

I would hate to go through this and then be right back where I started or worse. Any advice would be great! Also, I have fasted once before, it was a 6 day water fast. Tweet