Who is Kate Tolo, Bryan Johnson’s girlfriend and fellow biohacker?

Bryan Johnson, the American biohacker who went viral in the wake of the Netflix documentary Don’t Die: The Man Who Wants to Live Forever (2025), seems to overshare a lot. In a recent X post shared with his 1.5 million followers about his girlfriend, Kate Tolo, Johnson wrote, “Just gave Kate oral sex. Goodnight, everyone.” He followed this up with another TMI post, reading, “100/100 score. Top 1 per cent of all vaginas,” accompanied by a graph of Tolo’s vaginal health test results courtesy of at-home microbiome testing platform Tiny Health. After the post caught a wave of hate from Johnson’s followers, who called him an “incel” and his behaviour “psychopathic”, Tolo decided to weigh in herself. Alongside screenshots of Johnson’s post, Tolo wrote that she “could not be more proud” of her boyfriend for shining a spotlight on the typically taboo topic of vaginal health. But who is Tolo – beyond her vaginal test results, that is – and how did she become linked to the world’s most famous (or infamous) biohacker? Here’s everything to know about the Australian-Bosnian woman who proclaims to be a biohacker herself, aiming to become “the female Bryan Johnson”. She’s Bryan Johnson’s missing “puzzle piece” The pair first met in 2021 at Kernel, Johnson’s brain-computer interface company, where Tolo worked before joining him in his broader mission to re‑engineer human biology. The two have been dating for three and a half years. In a Facebook post from December 2025, Johnson recalled his first impression of Tolo as “luminescent” and shared how their “puzzle piece fit was immediate”. Later that month, he shared with his X followers how his biology was negatively impacted by his sweetheart’s absence. “Without her touch, my vagus nerve’s 100,000 myelinated fibres have dropped their high-frequency spectral power, squawking distress,” Johnson wrote. She traded fashion for longevity Before entering the biohacking sphere, Tolo worked in fashion, with stints at Proenza Schouler, R13 and The North Face. That creative background gave her a sharp eye for visual presentation, which she later channelled into working on Johnson’s projects. Today, she’s the co‑founder of ventures including Don’t Die, Immortals and Blueprint, all dedicated to pushing the boundaries of the human lifespan. Her current focus is Blueprint XX, a female‑specific version of Johnson’s anti‑ageing protocol. In 2023, Tolo became the first woman to test Johnson’s signature daily health routine, undergoing a 90-day trial that included a strict diet, supplementation and exercise, adjusted for female biology and hormonal differences. She has spoken openly about her aim to become the female version of Johnson, subjecting herself to scans and analysis to explore her biological age and metrics. She attends conferences and events dedicated to longevity alongside him – as well as social outings, such as Paris Hilton’s birthday party. She also shares biohacking posts on social media Tolo also shares longevity and health-related posts with her 100,000 Instagram followers, including ways to avoid jet lag, cure depression and heal your skin. In a recent post, she wrote about her own experience of struggling with acne for years and urged readers not to treat their skin like a “vanity” project. Like Johnson, she often posts about the difference between her chronological age and biological age. The pair recently announced that Tolo is about to become “the most measured female in history”. “We’re about to spend millions to measure and decode my biology through every phase of the menstrual cycle,” Tolo wrote on her Instagram and X.

Who is Kate Tolo, Bryan Johnson’s girlfriend and fellow biohacker?

.css-1c6uqr6{color:inherit;font-weight:inherit;font-size:inherit;font-family:inherit;line-height:inherit;overflow-wrap:break-word;}From fashion industry insider to longevity evangelist … Kate Tolo is the Australian-Bosnian Blueprint co-founder dating the Don’t Die star

From fashion industry insider to longevity evangelist … Kate Tolo is the Australian-Bosnian Blueprint co-founder dating the Don’t Die star