Biohacker Bryan Johnson has his girlfriends valuable menstrual blood in the freezer heres why

Forget love letters.Bryan Johnson is saving something a little more personal from Kate Tolo.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 pursuit of longevity.His girlfriend is increasingly becoming part of the show — and the couple’s latest science project is being kept on ice.“Kate’s period blood is in my -80 °C freezer,” Johnson recently wrote on X.

“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.“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 revelation comes as Tolo, 30, undergoes an intensive 100-day project to collect 14 million data points on her menstrual cycle.Johnson recently shared a glimpse into her daily routine, which is mapped out minute by minute and includes spitting into collection tubes, swabbing her cheek and using a high-tech tampon for deeper health tracking.The $2.6 million undertaking aims to help address gaps in medical research around female reproductive health.“I’m really doing it because I think that this is our path toward women being understood in the world and being seen,” Tolo told The Wall Street Journal in July.The effort follows Tolo’s diagnosis with endometriosis, a painful condition in which tissue grows outside the uterus, causing chronic pain, inflammation and scarring.“This affects at lea...