Cillian Murphy only ate an almond a day to prepare for his role in Oppenheimer: Emily Blunt

Cillian Murphy’s co-star Emily Blunt revealed that he only ate one almond in a day to transform into J Robert Oppenheimer for Christopher Nolan’s new film.

The eagerly-awaited Oppenheimer will be released in India on Friday. In a recent interview, actor Emily Blunt had spoken about Cillian Murphy's weight loss; he plays the lead J Robert Oppenheimer in the Christopher Nolan film.

Cillian Murphy plays J Robert Oppenheimer in Oppenheimer.

Speaking about how the role required drastic changes to his diet, Emily Blunt revealed what Cillian ate. She said to achieve his weight loss, which was necessary for the role, Cillian ate only ‘an almond’ per day.

Cillian Murphy's diet

In a recent interview, Emily Blunt told Extra, “He had such a monumental undertaking. And he could only eat, like, an almond every day. He was so emaciated.”

Cillian Murphy had told The New York Times in May this year, “I love acting with my body, and Oppenheimer had a very distinct physicality and silhouette, which I wanted to get right. I had to lose quite a bit of weight, and we worked with the costume and tailoring; he was very slim, almost emaciated, existed on martinis and cigarettes.”

Cillian on his weight loss

While Cillian Murphy didn't replicate J Robert Oppenheimer's reported diet – cigarettes and martinis – the exact methods he used to lose weight haven't been disclosed. However, it has been hinted that the diet was quite restrictive.

Speaking about his weight loss, Cillian recently mentioned that he almost got caught in unhealthy habits, pushing things a touch too far. "You become competitive with yourself a little bit which is not healthy. I don’t advise it," he told the Guardian in a recent interview.

About Oppenheimer

Christopher Nolan, known for films such as Tenet, Interstellar, Inception and The Prestige, has directed Oppenheimer. This marks the first time he has made a biopic of a real person – J Robert Oppenheimer (Cillian Murphy), the theoretical physicist, who helped develop the first nuclear weapons. Emily Blunt will be seen as his wife with a supporting cast that includes Robert Downey Jr, Matt Damon and Florence Pugh.

Oppenheimer will be released on July 21, alongside Greta Gerwig's Barbie featuring Margot Robbie in the lead role and Ryan Gosling as Ken.