I don't have sz but when I was psychotic I more or less stopped eating and lost a lot of weight. I thought I needed to cut out sugar and everything including good for you things like milk has sugar in it----I think also my head was so busy I didn't really get hungry/forgot to eat, however when I was in the hospital and food got put in front of me I ate it so it wasn't like a real eating disorder at all. I also got dehydrated because I developed issues with thinking someone was putting caffeine in my water at night and sleeping pills in the day so I had sort of rituals of how I would get my water so it wasn't poisoned.