Silicon Valley's longevity drug obsession is facing its first real reality check (opens in new tab)

Bryan Johnson, the tech entrepreneur who turned his body into a public experiment, stopped taking Rapamycin in September 2024 after several years of self-testing the drug. The immunosuppressant, which is clinically used to prevent organ rejection, had been a cornerstone of his longevity regimen since 2019. Over the years, he...