"I don't take steroids or anything like that. I follow an 'anti-aging' protocol prescribed by a specialist that includes testosterone replacement therapy," confessed Robert Kennedy Jr to Lex Fridman on his podcast a few years ago. With his virile jawline and sculpted body from demanding strength training sessions (which he 'executes' clad in his 'jeans'), the controversial Secretary of Health and Human Services under the Trump Administration, who has set out to "make America healthy again," embodies like no other, at 71 robust years old, that profile of a man, usually wealthy and powerful, who has found in testosterone an 'allegedly' infallible youth elixir.
Like Kennedy, Joe Bezos, Mel Gibson, Robbie Williams, or Hugh Jackman, to name a few well-known names, are part of that exclusive club of mature men who, beyond 50 and even 70, continue to display muscle mass resistant to sarcopenia - loss of muscle volume and function due to aging - and a sexual vigor typical of a thirty-year-old, thanks to testosterone replacement therapy, which requires thorough medical monitoring and should never be taken lightly.
"The use of testosterone replacement as an 'elixir of youth' is more based on cultural expectations and marketing than on solid evidence. Additionally, it is not without risks when there is no clear medical indication. My clear opinion is that testosterone supplementation should not be used unless there is a demonstrated deficiency in blood tests accompanied by clear symptoms of testosterone deficiency," states Ignacio Moncada, head of the Urology Department at Hospital Sanitas La Zarzuela and president of the Spanish Andrology Association.
Testosterone, he continues, "is not directly related to youth, but to functions that are more active during that stage of life such as morning erections, energy for sports, or work capacity. Therefore, naturally, testosterone is higher in the post-pubertal period, from 14 to 18 or 20 years old, and then gradually decreases over time. When this decline is more pronounced, as sometimes happens, accelerated 'aging' occurs, justifying its supplementary use to regain lost functions."
This specialist emphasizes that his prescription is not so much a matter of age but of when it is indicated. "It is true that testosterone deficiency occurs more frequently in adults over 55 or 60 years old who are noticing a reduction in their sexual desire and erections, their energy, or their ability to concentrate. When this is due to a decrease in testosterone levels in blood determined in an analysis, that is when replacement therapy can be initiated."
The treatment, he explains, can be administered "in two fundamentally ways, in a daily application gel applied to areas with little hair (shoulders or back) and absorbed through the skin, or in injections that can be given every three weeks (testosterone enanthate or cypionate) or every three months (testosterone undecanoate) which is more convenient. These are not expensive treatments and, in cases where there is a medical indication, they are covered by social security."
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Moncada emphasizes that when there is a real testosterone deficiency that warrants its use, the benefits are clear: "Among other functions, it improves sexual performance, enhancing desire and erections; it has somatic effects, increasing energy (stamina) and physical performance and concentration capacity; and it increases bone mineralization, helping to prevent osteoporosis, a common condition in elderly people. When the diagnosis clearly establishes the need for treatment, it is usually lifelong, as is the case with other hormonal deficiencies, such as hypothyroidism or diabetes."
The problem, he warns, arises "when there is no indication and there are excessive levels of testosterone in the blood, leading to adverse effects such as polycythemia, sleep apnea, particularly severe infertility in young individuals, or cardiovascular effects."
In his opinion, the fierce battle against aging that has found in this hormonal treatment one of its most effective weapons is not only a concern of the rich and famous. "They are not the only ones concerned about their health and hooked on testosterone. In our country, it is very common to see relatively young people obsessed with their physique or sexual capacity, something that, curiously, worries the older population less. Achieving eternal youth has always been an aspiration, and the use of testosterone may lead many to believe that it is the ideal path to achieve that. However, we know that aging is inevitable, and we must accept it as such, understand that we cannot fight against the passage of time. What should motivate us is to have healthy aging, maintaining a healthy and active lifestyle, engaging in moderate physical exercise, and following a healthy diet."
So far, the opinion of the president of the Spanish Andrology Association. How do medical professionals in clinics specialized in aging and longevity view this revolution?
A specialist in hormonal health at SHA Spain, Dr. Rafael Navas fully agrees with Moncada. "In our clinical practice, we use testosterone replacement therapy, but always within a rigorous medical framework. Its indication should be based on an individualized evaluation, with prior clinical tests and periodic monitoring. It is not a universal or default preventive treatment. We advocate for it when there is a justified medical indication. In certain patient profiles, it can be a valuable therapeutic tool, especially in the context of healthy aging, sarcopenia (muscle loss), persistent fatigue, or metabolic dysfunctions. But, as mentioned earlier, always within a multidisciplinary approach and with well-defined clinical criteria."
Navas warns that "uncontrolled use can increase the risk of cardiovascular events, liver alterations, dyslipidemia, or even stimulate certain latent neoplasms. Therefore, we insist that its prescription should always be based on objective medical criteria, with regular monitoring and under the supervision of qualified professionals."
An international reference in healthy aging and recognized for the third consecutive year with the title of World's Best Wellness Clinic 2024, at the world's most awarded wellness clinic, SHA considers ideal candidates for undergoing this protocol "individuals with confirmed hormonal deficiencies, muscle or strength loss, age-related functional decline, or certain metabolic disorders. It may also be considered for patients with accelerated aging or frailty. It is not recommended for young and healthy individuals solely for the purpose of improving physical or aesthetic performance."
Is this really the elixir of youth that is so talked about? "No. Although it can contribute to improving some functional markers of aging —such as muscle strength, bone density, or vitality— there is no solid evidence that it prolongs life in humans. The idea of the 'elixir of 'youth' is more of a marketing concept than a scientific reality. Healthy longevity is built on pillars such as nutrition, exercise, stress control, and medical prevention. Hormone therapy can be a complement, not a standalone solution."
According to Alfonso Galán, medical director of Grupo Neolife, "the relationship between testosterone and the pursuit of eternal youth is direct and evident. Testosterone is not that frivolous hormone that makes you want more sex and get ripped. It is a hormone that affects the brain, muscle, bone, cardiovascular system, skin, mood, and overall vitality. A person with adequate testosterone levels has more strength, better muscle tone, firmer skin, improved metabolism, better sexual function, less visceral fat, more confidence, more energy, better cognitive performance... In other words, better health and youth. It is not about 'rejuvenating' in a superficial sense, but about preventing or reversing processes that make us older. When you see a patient with low testosterone, they look like an elderly person, regardless of whether they are 42 or 78 years old. And when you restore physiological levels, it is not that they look young, but that they function like a young person."
The decrease in testosterone "does not give a clear and unmistakable signal, but the signs are there for those who can see them and for those of us with a lot of experience in this. In men, the typical change in silhouette is noticeable: thinning arms and legs, loss of muscle mass, appearance of a belly, more subdued character, less motivation, and poorer recovery after exertion. In women, who also have and need testosterone as much as men, we see it in the form of decreased sexual desire, looser skin, hair loss, or even in a decrease in physical and emotional performance. What is striking is that these changes are often attributed to 'natural aging,' when in reality they are signs of a perfectly correctable deficiency."
Muscular bodies and vigorous erections after 60. Are we in the era of the 'septuagenarian adolescent'? To what extent can this excess of testosterone influence an advanced age when it's 'no longer appropriate'? "It depends on what we mean by 'excess.' If we're talking about older people receiving testosterone at supra-physiological levels to build muscle or improve athletic performance, that's not what we advocate. In our clinic, we work to restore physiological levels, never to go beyond human biology. And at those levels, not only are there no undesirable effects, but there is an overall improvement in health, vitality, and prevention of degenerative diseases. So, if the question is: can a 75-year-old person have the vitality, strength, or sexual function of someone 20 or 30 years younger? The answer is yes. Due to excess? No. Due to restoration. Due to medicine," Galán concludes.