The trend known as reverse aging aims to slow down the aging process
By Florence Dujoux
The 2025 Netflix documentary Don’t Die: The Man Who Wants to Live Forever is a deep dive into the life of American entrepreneur and multi-billionaire Bryan Johnson that portrays his quest for immortality. On the agenda: intensive physical training, a strict vegan diet, highly managed sleep, a series of technologies (such as light therapy, electrostimulation, and hair-regrowth helmets), and the consumption of 130 daily supplements—not to mention a number of experimental treatments such as plasma injections and gene therapy.
With an annual budget of $2 million, a team of 30 people follows Johnson every day and analyzes his data in real time. Last year, the tech magnate claimed that his protocol lowered his biological age by five years—from 47 to 42.
The Dream of Immortality
“It’s really a marketing ploy,” says Benoit Arsenault, a full professor in the Department of Medicine at Université Laval in Quebec City. “There’s nothing scientific about it.”
On Johnson’s Project Blueprint website, you can buy the supplements he takes. If the approach of this tech bro—who sold his payment platform to PayPal for $800 million—is generating a lot of interest, that’s because he’s conducting his experiments on himself (this is called biohacking) and giving free access to his data. However, assessing the effectiveness of his protocol would require large-scale, long-term testing.
Arsenault says that immortality research doesn’t currently have a sound scientific basis. “Longevity protocols that use supplements, overtraining, gene therapy, and plasma donations aren’t supported by any evidence,” he adds. Their negative impacts can even outweigh their benefits. As a result, the Food and Drug Administration (FDA), the US agency responsible for public health, has issued an official warning against plasma transfusions from young donors.
Playing With Biological Age
No regulatory authority has validated the measurements of Johnson’s biological age, but you’ll soon be able to know your own thanks to a simple blood test. The amount of Klotho, an anti-aging protein produced in the kidneys, in the blood makes it possible to estimate and predict longevity in good health, according to Jean-Sébastien Paquette, a physician and researcher at Université Laval’s VITAM, a research centre in sustainable health. What interests scientists is that the level of Klotho decreases as people age but increases with good lifestyle habits.
Even though many experts are critical of Johnson’s approach, they give him credit for highlighting the dangers of highly processed foods, sedentariness, and insufficient sleep. By focusing on the secret of centenarians, Éric Simard, a doctor of biology and a researcher in cellular aging, has shown that these long-living people excelled in the four aspects of a healthy lifestyle: diet, physical activity, stress and anxiety management, and quality of social life, in addition to having a positive outlook.
“Lifestyle has an impact at the molecular level,” says Benoit Laurent, a professor in the Department of Biochemistry and Genomics at the Université de Sherbrooke in Sherbrooke, Que., and a researcher at the Centre for Research on Aging. Exercise slows down muscle decline, good nutrition promotes cell quality, and adequate sleep can help prevent cognitive decline.
The Birth of Geroscience
If it’s possible to have an impact on secondary aging, related to the environment and lifestyle habits, what about primary aging, which affects everyone eventually? In the 2000s, scientific publications showed that it was not just a question of wear and tear.
Ten years later, researchers found that aging can be explained by biological dysfunction. Advances in research led to a new discipline: geroscience. “Instead of treating each age-related disease—such as high blood pressure, diabetes, and dementia—one by one, geroscience treats them all at the same time by identifying their shared biological mechanisms when it comes to prevention,” says Dr. Gustavo Duque, a professor of geriatrics at McGill University in Montreal. Duque, who is also director of McGill’s Centre of Excellence for Sustainable Health of Seniors (Schouela CEDurable), emphasizes that the aim is to enhance longevity in good health (healthspan) rather than length of life (lifespan), which is too often promoted by private companies such as longevity clinics.
Laboratories in Overdrive
Longevity research draws on the work of Carlos Lopez-Otin, a professor of biochemistry and molecular biology at the University of Oviedo, Spain, who identified nine mechanisms of aging in 2013. Ten years later, he identified three more. Cell senescence is one of the best known. Senescent cells, or “zombie cells,” build up in the body with age instead of being eliminated. They secrete toxic substances that are involved in the emergence of age-related diseases. Senolytic medications, which flush out senescent cells, are already on the market. Initially used to fight cancer, they are now undergoing clinical trials on patients who have age-related diseases.
Concrete advances are also taking shape to counter the depletion of stem cells, which causes organs to deteriorate. Clinical trials led by Dr. Joshua Hare, a cardiologist and professor of medicine at the University of Miami and director of the Interdisciplinary Stem Cell Institute, treated the fragility of elderly people by injecting them with stem cells from young, healthy donors. The results included progress in terms of walking speed and muscle strength, reduced inflammation, and even temporary improvement of quality of life, without significant side effects. The next step is to optimize the dosage in collaboration with Longeveron, a biotechnology company co-founded by Hare, in order to obtain FDA approval.
Cellular reprogramming remains a future pathway. In 2012, the Japanese physician and researcher Shinya Yamanaka received a Nobel Prize for converting adult cells into pluripotent stem cells (which can differentiate into any type of the body’s cells). Given the difficulties around ethics approval and the risk of inducing cancer, scientists are targeting one organ instead of reprogramming the entire human body. In Japan, monkeys with Parkinson’s disease had their own stem cells injected into their brains. Because the results were so positive, a similar trial has been conducted on humans. “The idea is to repair aging organs with the patient’s own cells,” Laurent says.
Biotechs and Billionaires
A number of these scientific advances led to the creation of biotechnology companies, which have sparked interest in the finance community, such as the billionaires of Silicon Valley in southern California. According to the website Longevity Technology, which tracks financing campaigns in the sector, investments doubled between 2023 and 2024, reaching around $8.5 billion. The United States dominates the market, with 84 per cent of transactions.
California Life Sciences LLC (Calico), a subsidiary of Google founded in 2013, is one of the giants in the sector. Known for its slogan “Limitless Possibility Lives Here,” it develops anti-aging therapies in partnership with the laboratory Abbvie. In 2022, another giant, Altos Labs, attracted renowned researchers to work on cellular reprogramming. However, no innovations have been marketed yet.
Gaining 30 Years
Can science really help you live longer? “Epidemiological studies, parallels with experiments on animals, and data on human aging show that there are 30 years to play with in terms of human life expectancy,” Simard says— three extra decades to enjoy life in top form, from age 70 to 100. Duque believes that science has already significantly slowed aging: “At the moment, 70 is the new 40, and many people are living to 100 and more. We have begun to reverse aging, and this will be done even more in the future.”
