Bryan Johnson, the entrepreneur known for his extreme longevity regimen, recently announced his relationship with Kate Tolo, a 30-year-old Australian-Bosnian woman who he introduced as his girlfriend and a co-founder of his longevity startup, Blueprint. The two reportedly 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. They have been dating for about three and a half years, though Johnson recently made the news public in December 2025.
Tolo, who is also the Chief Marketing Officer of Blueprint, Don't Die, and Immortals, has been dubbed the "female Bryan Johnson." She is undertaking her own version of the Blueprint Protocol, specifically engineered for female biology. This ambitious project involves meticulously tracking a vast array of biomarkers, including cycles, blood work, stool tests, hormones, and sleep, to create an extensive female longevity dataset. Her personal mission aims to bring scientific insight into women's health challenges such as PMS, hormonal shifts, fertility issues, and endometriosis.
Johnson has publicly supported and promoted Tolo's endeavor, stating that she will likely become "the most measured female in history." A significant focus of Tolo's protocol is addressing suspected endometriosis, a condition affecting approximately 10% of women. Johnson has highlighted the importance of this specific research, noting that traditional diagnoses for endometriosis often take several years. Through Tolo's protocol, they aim to develop non-invasive diagnosis methods and potential treatments for the condition.
The relationship and Tolo's biohacking mission have generated considerable public interest, especially after Johnson's candid social media posts about Tolo's vaginal health test results. Tolo's journey is presented as a groundbreaking effort to fill a significant gap in medical research, which has historically prioritized male biological data. She hopes her rigorous self-experimentation will lead to advancements in understanding and treating female-specific health issues.
Prior to her involvement with Johnson's ventures, Tolo moved to New York at the age of 20 with aspirations of becoming a fashion designer. However, she became drawn to Johnson's work after reading about his neurotechnology and human well-being initiatives in late 2016. She reached out to him and eventually joined his team, first as his assistant, before becoming a key collaborator in his longevity projects and his romantic partner.
