Matt Damon has opened up about how he transformed his physique for a new movie role - and the one thing he had to cut out to drop 30lbs.
The actor, 55, is set to take on the lead role of Odysseus in Christopher Nolan's upcoming movie, Odyssey, set to be released in July 2026.
The upcoming epic action fantasy film is an adaptation of Homer's ancient Greek Odyssey, following Odysseus, the Greek king of Ithaca, and his long and perilous journey home to his wife, Penelope (Anne Hathaway), following the Trojan War.
As well as Damon and Hathaway, the all-star cast also includes Tom Holland, Zendaya, Robert Pattinson, and Lupita Nyong'o.
Damon addressed his preparation for the movie role on Jason and Travis Kelce's New Heights podcast on January 7, explaining the lifestyle changes he had to make.
Jason said that Damon looked "pretty yoked up" in some of the early shots that had been released from the movie, to which the actor responded that he got into "really good shape and lost a lot of weight".
Damon compared it to how the Kelces would prepare for games in the NFL, as being on shape becomes necessary as part of your job.
Revealing how he did it, Damon explained: "[Nolan] said he wanted me lean but strong, and so it's a weird thing, I don’t want to bore the s*** out of you but I literally, just because of this other thing I did with my doctor, stopped eating gluten.
"I used to walk around at between 185 [pounds] and 200 and I did that whole movie at 167. I haven’t been that light since high school.
"So it was a lot of training and a really strict diet."
Gluten is a protein that is found in wheat, rye, barley, and many processed foods made using these ingredients, including breads and pasta, and can cause a dietary intolerance in some individuals with Celiac disease.
This occurs when the body's immune system responds to the gluten, damaging the lining of the small intestine, per the Cleveland Clinic.
Despite Damon crediting a gluten-free diet for his weight loss, doctors have long dismissed it as a method to shift the pounds.
According to the Cleveland Clinic: "There’s absolutely no evidence that simply getting rid of gluten will result in weight loss. But if you eat a gluten-free diet you may make healthier food choices because you’re more aware of how to read food labels.
"Eating gluten-free often may cause you to eat more whole foods such as fruits, vegetables, legumes, and lean meats. These diet changes are often healthier and lower in calories."
As it stands, a completely gluten-free diet is only recommended for those who need to do it for health reasons.