https://x.com/bryan_johnson/status/2001755102043083161
Synopsis
Bryan Johnson reports results from a highly instrumented self-experiment exploring whether psilocybin could function as a longevity-relevant intervention. After two high-dose psilocybin sessions spaced three weeks apart, he observed multi-system biomarker changes that he argues are unusual given his already optimized baseline across sleep, nutrition, exercise, sauna, and hyperbaric oxygen therapy.
Johnson emphasizes that the signal was broad rather than isolated, spanning mental state, metabolic control, inflammation, hormonal stress markers, and brain network dynamics. Notably, continuous glucose monitoring showed a marked improvement in glycemic control following dosing, with reductions in mean glucose and variability that temporarily placed him in the extreme low-risk tail of population distributions. He interprets this as a possible “metabolic reset” mediated by brain plasticity, suggesting downstream effects on liver and pancreatic regulation that could, in theory, rival chronic metabolic medications. He notes durability for at least three days post-dose, though longer persistence remains untested.
Inflammatory markers also shifted favorably, with hsCRP falling to near or below detection thresholds after dosing, while stress hormones showed a pattern of acute activation during the psychedelic peak followed by suppressed cortisol and DHEA in the subsequent recovery window, consistent with a prolonged parasympathetic or “after-glow” phase. Estradiol rose substantially, which Johnson links to serotonergic effects on aromatase activity.
Neurophysiologically, brain connectivity data suggested inhibition of default mode networks and increased sensory-motor integration, aligning with subjective reports of increased openness, creativity, emotional range, and reduced cognitive rigidity. A second dose appeared additive, especially in auditory and language network integration, potentially influenced by the more social setting.
Johnson frames these findings cautiously, emphasizing that this is a single-subject experiment requiring replication, with pending analyses on epigenetics, telomere biology, and the microbiome. While he speculates that psilocybin-induced neuroplastic events could have downstream longevity relevance, he stops short of claiming clinical efficacy, positioning the work as hypothesis-generating rather than definitive.
mtc So great results. I remain skeptical, but hope it pans out. We’re evaluating our perceptions of a chemical whose primary effect is altering perception. There’s a bit of circularity there, me thinks…