Josh Duhamel, 52, reveals ‘taboo’ method he uses to ‘stay youthful and virile for as long as I can’

Josh Duhamel is turning back the clock — with a little help from modern medicine.

The “Transformers” star, 52, says he’s got the same energy he had in his 20s, but admits he’s kept quiet about what’s really been powering his second wind.

Now, with the launch of his new wellness brand, Duhamel is finally coming clean about the “taboo” therapy he’s relied on for the past five years to stay strong, sharp and camera-ready.

Duhamel first noticed something was off a few years ago — his energy was dipping, and the high-octane lifestyle he was used to suddenly felt like a grind.

“I took an inventory, a personal inventory, of how I was feeling, and I knew that I wasn’t quite where I was five, 10 years before,” he said Thursday at a Men’s Health Lab event in New York.

Eager for answers, Duhamel got some blood work done. The culprit was clear: low testosterone.

While some men maintain steady levels throughout life, most men start to see a gradual decline in their testosterone around age 40, according to Harvard Health.

It’s not the hormonal freefall women face during menopause. Instead, the drop is slow — about 1% a year — but by age 70, the average man is running 30% lower than his peak.

That drop can bring a long list of changes, including decreased muscle mass and strength, hair loss, weight gain, low libido, fatigue and mood swings.

The “All My Children” actor had heard about testosterone replacement therapy, or TRT, but only whispers.

“It was one of those things that I didn’t want to talk about,” Duhamel said. “Neither did anybody I was asking about it.”

Still, he decided to give it a shot.

“I started taking testosterone injections and began to feel really good,” Duhamel told Forbes in a recent interview, adding that he also began using hair growth treatments and longevity medicine.

“I had the urge to get back out and do the things I didn’t have the desire to do anymore,” he added, noting that he experienced little to no side effects.

TRT, a form of hormone therapy using anabolic steroids, can be administered through injections, oral meds, gels or patches. Its popularity is rising fast in the US, with prescriptions jumping from 7.3 million in 2019 to over 11 million in 2023, according to CBS News.

Over time, Duhamel’s motivation shifted from looking youthful to simply keeping up.

“I didn’t have my first kid until I was 40 years old, and then it was 52; I just had another one,” the actor said. “Overall, I want to stay as youthful and virile as I can for as long as I can.”

Even with such positive results, Duhamel kept his TRT use under wraps.

“Guys were asking me what I was doing and I didn’t want to talk about it,” Duhamel said on a recent episode of the Ed Mylett Show. “I just told them I was eating really well and working out but the truth is I was doing TRT,” adding that it still remains a “taboo thing.”

That fear nearly stopped him from going public — and from launching his new brand.

“At first, my representatives were like, ‘No, you’re not going to be the face of a testosterone company! That’s not something you talk about!’” he recalled. “And I was like, ‘Maybe it is!’”

Gatlan, Duhamel’s new venture, focuses on treatments to help men with hormone optimization, weight loss and hair thinning.

“We want to destigmatize something that men have been doing for years, and shine a light on it, and make it not so taboo,” he told Forbes. “You can look and feel better for much longer. Why not take advantage of modern medicine?”

Duhamel credits this regimen with helping him juggle fatherhood alongside demanding roles — including his latest as rancher Staten Kirkland in “Ransom Canyon,” a gritty Netflix drama about a man fighting to protect his family’s legacy.

After five years on TRT, Duhamel said the impact is clear when he takes a break.

“It’s less energy, a little harder to keep muscle on, and a little harder to keep the fat off,” he said at the Men’s Health Lab event. “You definitely can feel the difference.”