You go to a show and there's no food at all so if you're doing shows back to back you can forget eating. I remember standing up in the bath one day and there was a mirror in front of me and I was so thin! I hated it. I never liked being that skinny.
The experience of learning how to get straight to the core of a problem proved to be of immense value later when I had a long succession of responsibilities in large complex government departments.