Biohacker Bryan Johnson has sparked fresh controversy after revealing he’s storing girlfriend Kate Tolo’s “valuable” period blood in a -80C freezer to test for disease
Controversial biohacker Bryan Johnson has revealed he’s keeping his girlfriend’s “valuable” menstrual blood in a deep freezer. Moreover, he claims it could help unlock major clues about women’s health.
The tech entrepreneur turned biohacker has built a following by turning his quest to cheat death into a social media spectacle, documenting everything from his bodily functions to bedroom habits in the pursuit of longevity. His girlfriend, Kate Tolo, is increasingly becoming part of the show – and the couple’s latest science project has ignited more heated debates.
“Kate’s period blood is in my -80C freezer,” Johnson recently wrote on X (formerly Twitter). “Around 10 mL.”
The crimson keepsake, according to the Blueprint co-founder, is “valuable and underutilized”.
“It’s a non-invasive look into the uterus,” Johnson wrote. “She collected the blood during her last cycle.”
Johnson says the sample will be used to search for signs of diseased tissue, microplastics, endocrine disruptors and so-called “forever chemicals” known as PFAS, which can accumulate in the body over time, the New York Post reported.
“This is great because you get the data without surgical biopsy, it can be repeated every single cycle, and it measures the uterine environment directly instead of inferring it from a standard blood draw,” Johnson explained. The influencer says it’s part of an intensive, data-driven Blueprint-style project aimed at mapping female reproductive health – and ultimately curing Tolo’s endometriosis.
Kate, 30, is said to be undergoing a strict 100-day regime that tracks her menstrual cycle in extreme detail, racking up a claimed 14 million data points. Her daily protocol reportedly includes spitting into collection tubes, cheek swabbing, sleeping with an acrylic vaginal tracker, and even using a “techno-tampon” designed to extract deeper data.
Johnson claims the tracking has already uncovered diagnoses for Tolo, including polyendocrine metabolic ovarian syndrome and adenomyosis. Those are painful conditions linked to chronic, severe period pain.
He argues menstrual blood offers a direct “uterine blueprint”, containing endometrial tissue, immune cells and stem cells. He further says freezing a 10mL sample could help them examine the uterine environment without invasive surgical biopsies.
The billionaire infamously said his partner has a “top 1%” vagina after performing oral sex on her – and posting the results online. He said Tolo’s sample was “dominated by the single most protective bacterial species a vagina can host”, the Daily Star previously reported.
He posted on X at the time: “Just gave Kate oral sex. Goodnight everyone.”
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