Weight / Fat loss

I've never tried the 5/2 diet, which is why I was asking about it, so no that's not the point but thanks for your input.

Touchy much? You seem awfully defensive about it. I suppose I just skimmed your post stating you were consuming 600-700 calories a day and presumed you were talking about your :2 days. So the point definitely still stands, you were on a huge calorie deficit, then when you stopped you put weight back on. It's a fairly obvious outcome.