Tech titans are hacking their bodies for a longer life: is there science behind their methods?

In 2019, entrepreneur Bryan Johnson began to experiment on himself by taking daily injections of rapamycin. This immunosuppressant drug is typically used to prevent organ rejection after transplants, but the 48-year-old technology entrepreneur and venture capitalist had a different goal — to extend his life .

Are health influencers making us sick?

He tested several protocols, experimenting with weekly, biweekly and other schedules. He tried 5-milligram doses as well as 6-mg and 10-mg ones. But in September 2024, Johnson decided to end his personal trial with rapamycin: the benefits didn’t outweigh the drawbacks, which Johnson outlined in a post on social-media platform X . He had intermittent skin infections, high glucose levels and abnormalities in his blood lipid levels, plus a heightened resting heart rate. “With no other underlying causes identified, we suspected Rapamycin, and since dosage adjustments had no effect, we decided to discontinue it entirely,” he wrote.

Johnson, who sold his mobile-payment business Braintree to financial-technology firm PayPal in 2013 for US$800 million, often tinkers with his daily regimen of drugs, peptides in the form of both supplements and injections and other medical interventions in pursuit of a longer life. He’s part of a growing crowd of tech entrepreneurs who are seeking extra years by hacking their own bodies — and sharing their exploits widely through social media and other channels.

Johnson’s Blueprint protocol — a self-published guide to his life changes and medical choices — has been adapted over time. He and his team told Nature that “the new focus of our protocol is to tackle chronic conditions that current medicine accepts as manageable but not treatable, and to render them treatable through advanced diagnostics and next-generation personalized therapeutics”.

As with Johnson and rapamycin, it’s not uncommon for these biohacking influencers to suddenly stop using a product that they previously thought would help them to extend their lives. For years, supplements called exogenous ketones — which raise ketone levels in the blood, lower blood glucose and supposedly improve cognition — were widely embraced in Silicon Valley circles. The compounds were sold as a premium cognition aid and a stimulant for executives.

In March, however, entrepreneur Tim Ferriss and venture capitalist Kevin Rose used their popular podcast to warn listeners about taking supplements that contain a compound called 1,3-butanediol. Emerging data from animal models, said Ferriss, indicate that it might give mice a condition similar to fatty liver disease. “Treat it like ethanol,” he warned, “like you’re drinking moonshine and you wouldn’t want to do that every day.” The animal findings have not been confirmed in human studies, and some manufacturers dispute the characterization.

This supplement joins a long list of life-extension tricks that tech leaders have latched onto despite questions about their effectiveness and safety. In 2019 and again in 2024, the US Food and Drug Administration (FDA) warned against ‘young plasma’ infusions , in which people receive blood transfusions from young individuals . These infusions are being promoted as an anti-ageing therapy — and are something that Johnson regularly incorporates into his wellness regimen, courtesy of his son.

Bryan Johnson was featured in a 2025 documentary Don’t Die: The Man Who Wants to Live Forever . Credit: Netflix/Everett/Shutterstock

Tech entrepreneur and billionaire Peter Thiel told Bloomberg News in 2014 that he takes human growth hormone in hopes of living for 120 years, despite the Mayo Clinic, a renowned US medical centre, warning of substantial risks and saying that there is little evidence that the drug helps healthy adults to regain youth or energy. Thiel did not respond to Nature ’s questions about whether he still takes the hormone or what he makes of the Mayo Clinic’s guidance.

In hopes of enhancing cognition, some Silicon Valley tech leaders have touted methylene blue, a compound with a long history as a textile dye that has been approved for limited medical use, mainly to treat a rare blood disorder. And they are promoting nicotine pouches — marketed as an alternative to smoking — as a way to optimize focus and energy, despite well-documented concerns about addiction.

These wealthy longevity evangelists are often seen as translators of early-stage science to the public, who turn preliminary or anecdotal findings into so-called stacks that combine supplements, other compounds, protocols and therapies, long before FDA approval. “It’s a trickle-down effect due to the nature of platforms they use to spread their content,” says Margje Camps, a researcher at the University of Utrecht in the Netherlands who studies health influencers.

But there is a danger to this growing phenomenon: researchers who study ageing and longevity warn that these biohacks have not been clinically tested, meaning that it’s unclear whether they…