"Leonardo needs to shed at least 30lbs. He's gained weight recently and looks almost a bit flabby, which isn't good, especially as the camera adds pounds. "There's an action scene coming up at the end of the year in which he needs to appear emaciated, so the pressure is on," said a source.
Although Leonardo - who plays Jacob Hastley in the film, which is about an officer worker who becomes involved in a blackmail scandal - is finding it hard to cut out calorific treats, he is determined to be in top shape for the scene.
The movie source said: "He is following a strict diet and is embarking on a rigorous workout regime. Leonardo is a pretty determined kind of guy, when he sets his mind to things he always achieves them. Though this is going to be hard for him, you can guarantee he'll succeed."
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