The actor plays the lead in new movie jOBS and he did all he could to accurately portray the late Apple boffin, even changing his eating plan to include just fruits, nuts and seeds.
However, Kutcher was left ""doubled over in pain"" after sticking to the diet, and sought medical advice in hospital.
He tells the Associated Press, ""(The diet) can lead to some serious issues. I ended up in the hospital two days before we started shooting the movie.
""I was like doubled over in pain, and my pancreas levels were completely out of whack, which was completely terrifying, considering everything.""
Jobs died of complications from pancreatic cancer in 2011.