In an interview with Yahoo Movies, DiCaprio says that The Revenant was one of the most challenging of his career.
I can name 30 or 40 sequences that were some of the most difficult things I’ve ever had to do. Whether it’s going in and out of frozen rivers or sleeping in animal carcasses or what I ate on set. [I was] enduring freezing cold and possible hypothermia constantly. I certainly don’t eat raw bison liver on a regular basis. When you see the movie, you’ll see my reaction to it because Alejandro [Inarritu] kept it in. It says it all. It was an instinctive reaction.
On talk that some staff left the film:
I wasn’t privy to exactly what went on. But to me, most of the people were there working incredibly hard, and they should be given due credit for the effort they gave this movie because everyone I saw was giving their heart and soul to pursuing his vision.