Matt Damon Told Stephen Colbert His Cat Is “Jacked.” Is That a Thing? · Kinship

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Can Cats Get “Jacked” on Steroids? Matt Damon Says His Did

The Oscar winner says his cat was prescribed life-saving steroids and is now “like Arnold Schwarzenegger.” Could that be true?

Small orange cat walking on dumbbells in gym.
Dina V / Shutterstock

Let me start this off by saying that I am a gullible person. April Fools’ Day is... challenging for me. When, on April 1, my favorite movie theater in Brooklyn posted that they were instituting a “no shoes” policy this spring, I seriously considered my future as a barefoot moviegoer before realizing that is completely against health codes in an establishment that serves food. Bested again by the national day of pranks. 

So, when Matt Damon went on The Late Show With Stephen Colbert (on April Fools’ Day, funnily enough), and said his cat had been on a ton of steroids and got “jacked,” I took him seriously. I turned to my co-worker and said, “Really? Like Kristen Stewart’s bodybuilder girlfriend in Love Lies Bleeding?”

No, not really, Hilary, you ridiculous 32-year-old woman who should never be allowed to answer the phone, because you’ll likely get scammed. Another farcical comment that I fed right into.

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The story of the jacked cat

In my defense, Damon was convincing. The man has won awards for acting, OK? He told Colbert about his cat, whom his family adopted in Costa Rica about 10 years ago. This guy is a real badass, the actor said: “He was living by himself in the jungle. He was the coolest cat you’ve ever seen. I mean, he was hunting — he had two giant holes in his side. He was fighting for his life every night.” 

Damon’s family was staying at an Airbnb near where the cat lived and fed him every day for a month. So, of course they brought the jungle kitty home with them, where he got used to lounging about and, per Damon, “never went outside ever again,” as is his right. Unfortunately, the cat ended up with a brain tumor, and by the time Damon’s family moved to New York in 2021, he had lost a lot of weight and was walking in circles. 

They took him into the Schwarzman Animal Medical Center (AMC), where cat neurologist Dr. Chad West offered a Hail Mary of sorts, per Damon: “Chad said, ‘I mean, I could give him, like, a bunch of steroids.’”

Damon fast-forwarded his story to the present to confirm that the cat indeed survived: “That was two-and-a-half years ago … now he’s jacked. And I joke that he’s like Arnold Schwarzenegger … He’s, like, got muscles on muscles.”

AMC even proudly posted the clip:

Steroid treatment and cats: an investigation

So, yes, that is a joke. But I started thinking, Maybe this can happen. I’m personally acquainted with many cats, but none have told me of their personal fitness goals. So, I consulted Dr. Gabrielle Fadl, a New York City-based veterinarian who’s consulted with Dr. West on some of her clients in the past (I reached out to Dr. West’s office with no response). Dr. Fadl politely refrained from laughing at me when I asked the following questions. 

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This interview was edited for length and clarity. 

So, can a cat get jacked from steroids prescribed by a vet? That was a joke, right?

Dr. Gabrielle Fadl: That was a joke. We’re using glucocorticoids — like Prednisolone — which is, I’m sure, what [Dr. West] used for this cat. That helps to reduce inflammation and it can be chemotherapeutic in its own regard, oftentimes used in conjunction with other things, but it can help reduce inflammation, sometimes shrink down the sizes of tumors or at least the inflammation associated with tumors.

But it doesn’t make them jacked. Those are more like anabolic steroids, which we don’t really use in animals.

So, that cannot happen, at least from a steroid?

No, but I did have a client joke with me once when I put his pet on steroids. He was like, “Doc, what’s goin’ on? I came home, and the dog was bench-pressing the couch.” I was like, “What?!” But I loved it. I thought, That is the greatest thing anyone has ever said to me.

Some cats are just more muscular than others. You could call a cat jacked, right? Just not from a steroid?

Not from a steroid. But, some of the side effects from steroids include making you eat more, and so a lot of these cats will gain weight because they’re eating better, they feel better. So, they can gain weight because they’re feeling better, but they’re not, like, ripped

Is what Dr. West did — kind of a last-ditch-effort — when you would most usually use steroids for a tumor?

It is truly one of those things where you’re like, “If there’s nothing else to do, we can just try steroids.” It comes with side effects where it can be dangerous long-term: You can become diabetic, you can go into heart failure. High doses of steroids for a long time can cause these things, but it also really works well, and so it’s kind of like a Hail Mary that we’ll use.

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Would you use steroids in other instances?

So, steroids have a lot, a lot, a lot of clinical indications at different doses, different frequencies, so it can be used for cancer, to reduce inflammation; it can reduce tumor size. It can be used for certain conditions where the pet is not making their own steroids from their adrenal glands, something called Addison’s disease.

We’ll use it for itchy skin in some patients. We’ll use it for immunosuppression, so if a pet has an autoimmune condition, you can use it at higher doses to suppress the immune system. That’s not great for long-term use as you can imagine, but we’ll start them off high and then taper them off when they’re feeling better. 

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OK, so back to this jacked thing. If a cat would be extra muscular, is it a... problem?

No, I don’t think so. As long as they’re a good body weight, and they’re eating a balanced diet. I don’t know if I’ve ever seen a truly jacked cat. I’ve seen fuller cats, but they also have so much skin. So, you’re not seeing what you see in a dog — like a Pit Bull or something — when they’re ripped. Interesting question. I don’t know if I’ve ever been asked that. 

Well, I see people on TikTok with their cats who say “He’s not fat, he’s just big-boned.”

Yeah, most of those cats are just fat. 

References:

Addison’s Disease in Cats

Hilary Weaver

Hilary Weaver is the senior editor at Kinship. She has previously been an editor at The Spruce Pets, ELLE, and The Cut. She was a staff writer at Vanity Fair from 2016 to 2019, and her work has been featured in Esquire, Refinery 29, BuzzFeed, Parade, and more. She lives with her herding pups, Georgie and Charlie.