Jennifer Aniston Reveals Downside to Letting Herself Go for 'Cake'

PHOTO: Jennifer Aniston in a scene from "Cake." Aniston was nominated for a Golden Globe for best actress in a drama for her role in the film, Dec. 11, 2014.Cinelou Films/AP Photo
Jennifer Aniston in a scene from "Cake." Aniston was nominated for a Golden Globe for best actress in a drama for her role in the film, Dec. 11, 2014.

Jennifer Aniston is getting some serious Oscar buzz for her role in "Cake," but the actress recently said letting herself go for the acclaimed role did come with some negative side effects.

On an episode of the "Dr. Oz Show" that aired today, Aniston, 45, talked about playing a character Claire Simmons in the movie, that deals with chronic pain and how she had to stop working out for a while to make the part convincing to the audience.

This lack of exercise really affected her in the real world.

"It really was interesting when you stop working out how you just ... my serotonin levels went down. My stamina was shot. I was cranky. I was irritable," she said on the show in a clip obtained by US Weekly. "I found myself short. I was hungry like crazy."

She said the role made here realize how important fitness is in her life.

"[It's] important to our soul, not just being able to fit into skinny jeans," she added. "Just your state of mind, your soul, all of that."