The movie star adopted Jobs' fruitarian diet and even tried to follow the rules of a nutritional guide the computer entrepreneur lived by to perfect his portrayal in Jobs - but the health overhaul left him skinny and ill.
Kutcher tells Wenn, "I went on this fruitarian diet and I read a book by this guy, which was a book that Steve read called The Mucus Free Diet Healing System and it was his dietary bible. It talked about the value of grape sugar and that was the purest sugar you could have in your body.
"I think the guy who wrote that book is pretty misinformed and my insulin levels got pretty messed up and my pancreas kind of went into something... It was pretty painful. I didn't know what was wrong. We figured out my insulin levels were really off."
Jobs director Joshua Michael Stern adds, "He lost, like, 15 pounds at the beginning and went on a fruitarian diet and ended up having to go to the emergency room."