Did Ryan's weight gain get him fired?

Why did Ryan Gosling leave the production of The Lovely Bones? A source says the 26-year-old "was fired" because "he just gained too much weight!" A second insider says, "He ate grilled cheese every day." But pigging out reportedly wasn't the only problem. Adds the source, "He drove the hair and wardrobe crew crazy." A DreamWorks rep said of the story, "We have huge respect for Ryan's work. It was truly a case of creative differences, plain and simple."