Doctor Explains Truth Behind Testosterone Therapy as Josh Duhamel Says Treatment Made Him ‘stronger’

Josh Duhamel’s Experience With Testosterone Replacement Therapy

Hollywood actor and former model Josh Duhamel, 53, has brought renewed public attention to hormone health after sharing his personal journey with testosterone replacement therapy (TRT). Appearing on Dave Asprey’s ‘The Human Upgrade’ podcast on 16 September, Duhamel revealed that he discovered he was living with low testosterone levels during his early 40s. To manage the condition, known clinically as hypogonadism, Duhamel now administers testosterone injections three times per week to restore his hormone levels.

Describing the physical impact of the intervention, Duhamel highlighted significant relief in his overall vitality and joint health. “I feel better now than I did in my early to mid-30s,” the actor said. “I’m not even kidding you. My joints, my back, my knees. I just feel stronger.” While the medically supervised regimen has yielded positive outcomes for Duhamel, healthcare experts warn that the wider public perception of TRT is increasingly becoming detached from clinical indications.

The Surge in TRT and the Rise of ‘Physique Culture’

Testosterone replacement therapy is intended as a medically supervised hormone treatment designed specifically to restore levels in men diagnosed with hypogonadism. However, epidemiological trends show a sharp uptick in wider consumption. Data from Epic Research indicates that the proportion of male patients receiving testosterone prescriptions has been steadily increasing since 2021.

According to the American Osteopathic Association, this rising demand is fueled significantly by social media and an intensifying crisis dubbed “physique culture.” In these instances, men pursue off-label testosterone use not to treat a documented medical disorder, but to accelerate muscle growth, trim body fat, and pursue an idealized body composition. Compounding this, Harvard Health reports that men naturally experience an approximate 1 percent decrease in testosterone annually after reaching age 30 or 40. Aggressive marketing campaigns from digital health platforms frequently pathologize this natural physiological slowdown, branding it as a condition that requires “fixing.”

Taking exogenous testosterone without a legitimate medical deficiency carries severe physiological consequences. When an individual with healthy baseline levels introduces external hormones, the body registers the surplus and suppresses its endogenous production. This negative feedback loop can trigger side effects such as testicular shrinkage and long-term infertility. Conversely, for patients with true clinical hypogonadism—marked by loss of libido, depleted muscle mass, elevated body fat, and osteoporosis—properly managed TRT remains an established, doctor-prescribed treatment.

Medical Realities: Diagnosis, Stigma, and Symptoms

Speaking directly to LADbible, Dr Fraser Gordon, an NHS consultant physician and medical director at Xvera, outlined the clinical landscape of androgen deficiency. Dr Gordon noted that the condition is widespread yet routinely overlooked because its presentation mimics other health issues.

“It is more common than most men realise,” he said. “In one large European study, around one in six men aged 40–79 had testosterone levels in the low or borderline range. But the difficulty is that it can be remarkably easy to miss. That is made even worse because, as men, we are often brilliant at ignoring symptoms and putting them down to stress, getting older, work or simply life. And because low testosterone can present with reduced libido, lower energy, erectile problems, loss of muscle mass or strength, and changes in mood or concentration, it is very easy to explain those symptoms away rather than think they may have a medical cause.”

Dr Gordon cautioned that self-diagnosis based on generic complaints is unsafe, noting that systemic factors frequently cloud the clinical picture. “Poor sleep can make you tired. Stress can affect libido. Obesity can affect testosterone. Depression, medication, thyroid disease and anaemia can all produce overlapping symptoms. That is what makes diagnosing testosterone deficiency much more complicated than simply ticking a few symptoms on a questionnaire.”

Despite these complexities, Dr Gordon welcomed high-profile transparency from public figures like Duhamel. “I actually think celebrity stories like this can be extremely useful, as they get men talking about something many of us are exceptionally good at ignoring: our own health. If your energy has changed, your libido has disappeared, your sexual function has changed, you are losing strength, or you simply no longer feel like yourself, it is reasonable to find out why.”

Therapeutic Dosing Versus Performance Enhancement

Clarifying the fundamental difference between clinical hormone replacement and illicit anabolic steroid use, Dr Gordon dispelled common misconceptions surrounding the therapy. “Most of us immediately think about bodybuilding and that heavily ‘juiced’ look. But medical TRT is not the same thing. We don’t give people huge amounts of testosterone or push their levels to those seen with bodybuilding. It is purely there to replace testosterone that their body is no longer producing adequately and bring it back into a normal range. For a man who genuinely has testosterone deficiency, TRT can be a game changer. It improves libido and sexual symptoms, and can improve things such as muscle mass, body composition and overall wellbeing. But it is not a magic anti-ageing drug. It is replacing what should be there already.”

Safety parameters mandate continuous clinical monitoring once therapy begins to evaluate symptom resolution and safeguard internal health. Among the most critical considerations is the negative impact on family planning. Exogenous testosterone disrupts the biological signals that prompt the testes to generate sperm and endogenous hormones.

“If somebody wants children now or in the future, that conversation needs to happen before treatment starts, not six months afterwards. There are other approaches TRT specialists can sometimes consider where preserving fertility is particularly important. This is why you need the oversight and input of doctors trained in these areas,” Dr Gordon emphasized.

Why This Matters

The conversation sparked by Josh Duhamel shines a light on a growing public health intersection: legitimate endocrine medicine versus cosmetic hormone use. As direct-to-consumer health companies and social media trends continue to promote testosterone optimization, distinguishing between clinical pathology and standard age-related changes is crucial. Unregulated or non-indicated hormone use poses long-term risks to endocrine stability, natural hormone production, and male fertility. Rigorous diagnostic evaluation and sustained medical supervision remain imperative to protect patients from the hazards of self-directed therapy while ensuring those with hypogonadism receive appropriate care.

Frequently Asked Questions

What is the difference between medical TRT and off-label testosterone use?

Medical TRT is a supervised clinical therapy prescribed exclusively for men with diagnosed deficiencies (hypogonadism) to bring their testosterone levels back to a normal physiological baseline. Off-label use often involves individuals with normal baseline levels taking external hormones—frequently in higher doses driven by bodybuilding or aesthetic goals—which can disrupt natural endocrine function.

How does external testosterone affect male fertility?

When an individual takes exogenous testosterone, the body perceives the excess and turns off the internal signaling mechanisms that prompt the testes to produce natural testosterone and sperm. This can cause testicular shrinkage and acute or long-term infertility, which is why medical providers urge patients planning to have children to discuss fertility preservation before initiating treatment.

Can lifestyle factors cause symptoms similar to low testosterone?

Yes. Common symptoms of low testosterone—such as fatigue, low libido, muscle weakness, and low mood—can also be caused by poor sleep, chronic stress, obesity, depression, medication side effects, anemia, or thyroid disorders. A comprehensive evaluation by a qualified doctor is required to establish whether testosterone deficiency is truly the underlying cause.