ianrobo wrote:You would not lose that as muscle loss after being ill for a few days, likely that is all water loss
Possibly. But not necessarily.
I lost 3/4 of a stone during 5 days in hospital for surgery (which didn't take out anything of any weight, and I'd had before without losing any weight). I was very well hydrated, and was, of course, not taking exercise. It was pure stress. It stayed off for months, as the stress remained due to the problems I'd experienced in the hospital, so again, definitely not water. I can easily lose a couple of pounds, and not merely temporarily, if I'm under severe stress for a few days, despite still eating normally and keeping my fluid intake up.