Bryan Johnson - who has turned himself into a walking longevity experiment, spending millions to reverse ageing and documenting every biomarker imaginable - recently took 5.24 grams of psilocybin mushrooms while livestreaming the experience and vibing to Grimes, in what was a weird yet oddly intriguing, and potentially seminal, cultural moment.
Well, Johnson posted some data from the experiment on X, and it's kind of fascinating.
The Numbers Tell a Story
Here's what makes this trip (his 2nd out of a planned 3) more interesting than most: Johnson measured everything before and after his trip, and some of the changes are pretty striking.
Inflammation basically disappeared. His hsCRP (a marker of systemic inflammation) dropped from 0.23 mg/dL to below the detection limit of 0.15 mg/dL. That's over a 35% decrease. For context, this aligns with actual clinical studies showing reduced inflammatory markers like CRP, TNF-alpha, and IL-6 after high-dose psilocybin.
His stress markers tanked. Five days post-trip, his cortisol dropped 42% and his DHEA-S fell 45%. Now, this is where it gets nuanced. Cortisol actually spikes during the trip itself (more on that in a second), but afterwards, his body shifted into what he calls "parasympathetic dominance", which is basically a deep relaxation mode. He describes feeling sustained joy and relaxation, which tracks with what researchers call the psilocybin "afterglow effect."
Estradiol tripled. This one's interesting for the neuroscience nerds. His estradiol (a form of estrogen) went from 11.3 to 36 pg/ml, likely because psilocybin activates 5HT2A receptors that stimulate aromatase, the enzyme converting testosterone to estradiol. His testosterone stayed the same, meaning his body just compensated. And estradiol isn't bad here. It's actually neuroprotective and anti-inflammatory.
Thermal Imaging
Here's where Johnson really goes full mad scientist. He created thermal maps of his face and body during the trip. This is apparently a first-of-its-kind visualisation of what a psychedelic experience looks like physiologically.
His core body temperature rose about 1.5-2°F (matching clinical studies on psilocybin). His chest and throat heated up 2.5°F, creating what he calls a "thoracic heat bloom" visible on thermal imaging. Meanwhile, his nose and lips cooled, indicating emotional intensity. His cheeks warmed (joy, connection, sadness), his forehead cooled (introspection, cognitive effort), and his arms cooled from peripheral vasoconstriction.
During the peak at 2.5 hours, his heart rate jumped from 55 to 70 bpm, and his fingertip oxygen saturation dropped from 99% to 94% - all signs of sympathetic nervous system activation and reduced blood flow to extremities.
Magic Mushrooms For Longevity
Why is the world's most famous death defier turning to shrooms, you may ask. Well its' because of a fascinating study published in July 2025.
The groundbreaking paper published in npj Aging suggests that psilocybin may actually slow cellular ageing and extend lifespan by reducing stress, protecting DNA, and extending the number of times a cell can divide before it senesces.
The second part of the study saw researchers give aging mice psilocybin once per month for ten months.
The results were remarkable. Survival rates jumped from 50% to 80%, and the treated mice looked younger, with smoother coats, darker fur regrowth, and healthier skin.
This is the first-ever experimental evidence that a psychedelic compound can delay senescence (cellular ageing) and improve survival in aged animals. And it’s sparking major interest among longevity researchers like biohacker Bryan Johnson.
The Human Side
What I find just as compelling as the biomarkers is what Johnson wrote the day after. He called it "one of the best days of my life," describing it as "healing, energizing and full of love."
He livestreamed the whole thing with his team, and apparently it became this shared experience that had people calling their parents and loved ones afterwards to express gratitude.
There's something genuinely touching about someone who's built his entire brand on optimisation and data suddenly talking about hope and human connection.
What to Make of This
Look, Bryan Johnson is a lot. The whole longevity obsession can feel dystopian and off-putting. Especially the blood transfusion from his son. But I think what he's doing here (measuring the physiological impacts of psychedelics with serious rigour) is actually very valuable. We're in the middle of a psychedelic research renaissance, and more data is always better than less.
The inflammation reduction alone is noteworthy. Chronic inflammation is linked to basically every age-related disease and mental health condition, and if psilocybin can demonstrably lower it (which multiple studies now suggest), that's a big deal.
That said, let's be clear. This is n=1 data from a guy who can afford to measure every possible biomarker and has a vested interest in proving his experiments work. It's compelling, but it's not clinical research. And 5.24 grams is a hefty dose and not something most people should casually try at home.
Still, Johnson's conclusion feels right. These results suggest psilocybin can push biology "into a low inflammation, low stress configuration that is theoretically favorable for longevity."
But if nothing else, watching Silicon Valley's most obsessive biohacker find healing through mushrooms and come out talking about love and connection is a narrative twist I'm all for. And maybe it will prove to be a watershed moment, not just in the psychedelic renaissance, but in popular culture.
