I recall back in the early '90s (around the Passion & Warfare album) Steve Vai was extolling protracted fasting as a means by which to connect with some inner creative force. He didn't have a weight problem that's for sure. He was writing a series of Zen-themed Guitar Player articles around that time. I recall reading an unsettling yet intriguing (for an impressionable me) GP interview quote along the lines of "after (x) days of total fasting, every cell in your body is crying out...". It worked for him I guess. On the other hand, EVH accomplished a lot with a Marlboro and a variac.