Tech millionaire Bryan Johnson has revealed he spends nearly £12,000 on lab equipment to track his girlfriend Kate Tolo's "nocturnal erections" as a health marker. The 49-year-old biohacker, known for spending large sums to reverse his biological age to 18, said women get erections just like men.
Women have erections too
Writing on X, Johnson acknowledged his latest experiment would leave most people confused. "Women have erections too. This is news for most women," he said. "The clitoris is erectile tissue, same as men. During REM sleep, blood flow spontaneously increases. This is a non-sexual, normal sleep function."
While most associate erections with male anatomy, Johnson insists tracking night-time arousal patterns is a "Tier-1 health marker" for both sexes. "In men, ED typically shows up 2-5 years before heart symptoms," he said, boasting he averages three-plus hours of "boners" every night over four to five separate episodes. "It's one of the best signals I have for my health... We will see how many Kate has."
Lab equipment setup
Johnson tracks his own nightly activity using a wireless $275 (£207) gadget, but Tolo's setup costs significantly more. Her $15,700 (£11,800) equipment involves a 5cm light-sensor probe attached to a wire taped directly to her leg, feeding live data into a bedside laptop kept switched on overnight.
"Hers is lab equipment, it runs through a wire taped to her leg, into a machine and streams into a laptop that cannot be allowed to fall asleep," Johnson wrote. He defended the test, adding: "Night-time erections are downstream of whole body health including blood vessels, nerves, hormones, sleep stages, stress, glucose, and cardiovascular health."
Part of Blueprint project
Tolo said: "Men's nighttime erections have been studied extensively for decades...Women's are barely measured. If the data turns out to matter the way it matters for men, someone should build the device." The probe is one of 1,900 biomarkers Tolo is tracking across her menstrual cycle for Johnson's "Blueprint" anti-ageing project.
The former North Face executive, who moved to the US from Australia at 20, has been dating Johnson for several years. She has previously spoken about how their romantic and professional lives "all bleed into one" and has revealed she sleeps with an acrylic vaginal "techno-tampon" to measure period blood flow. Johnson, who previously made headlines for injecting blood from his teenage son, taking 100-plus daily pills and eating his final meal at 11.30am, claims his measuring will help him live until he's 150.
