Leonardo DiCaprio in The Reverent
This one is hard to compete with – during his role in The Reverent, DiCaprio slept inside real animal carcasses. This becomes that much harder when you’re a given – like Leonardo DiCaprio.
Not only did he sleep inside dead animals, but he also had to break his vegan lifestyle by eating raw meat. This seems like one of the biggest sacrifices actors did for a role, taking method acting to the extreme.