Bryan Johnson@bryan_johnson
Two doses of magic mushrooms degraded my sperm count from the 99.6th percentile to the 77.7th.
This may be a first-in-human observation.
Context: we ran the most quantified magic mushroom (psilocybin) experiment ever conducted. We were asking if psilocybin is a longevity therapy. After seeing the data, we think it is (see reply post for the experiment summary).
Also, like most things biology: the results are complicated.
My data suggests that the magic mushrooms (psilocybin) negatively impacted my fertility markers.
Before the first psilocybin dose my motile sperm count was at 99.6th percentile for men under 25 years of age, it dropped to 77.7% and partially recovered to 89.3% following the first dose, and second doses, compared to the same age cohort (numbers compare similarly to my age cohort as well).
3 days following my second dose (first dose 25 mg, second dose 28 mg)
. Motility: dropped 51%
. Total count: almost unchanged, dropped by 2%
. Total motile count: dropped 52%
. Normal morphology: dropped by 50%
20 days post 2nd dose, the pattern continued, with typical latent effects on total sperm counts
Motility: recovered back to -2% of pre-psilocybin baseline:
. Total count: dropped by 38%, latent effect.
. Total motile count: remained inhibited at -39% of pre-psilocybin baseline, (despite motility normalizing, due to the total count drop)
. Morphology normalized to -10% of baseline levels.
Reduction in free testosterone might have contributed to the effect.
While total serum testosterone increased by 30% 3 days following the 2nd dose (neither FSH or LH were meaningfully affected either), and continued to be at 11% above baseline, SHBG increased by 37%, SHBG binds testosterone and reduces its bioavailability and activity. My free testosterone (direct) showed 24% and 23% drops at 3 and 20 days post 2nd dose.
In light of the neuroplastic, well-being, brain reset, and systemic metabolic and anti-inflammatory benefits, the trade-off is probably worth it. Especially considering that the magnitude of inhibition has no meaningful effect on actual fertility (total motile counts above 50 million are still on the safe side).
This is a first-in-human observation, to our knowledge there is no published human clinical study demonstrating that psilocybin diminishes male fertility markers.
General mechanistic evidence exists for recreational and psychoactive drugs possibly inhibiting fertility markers due to their effects on the hypothalamus-pituitary-adrenal axis and general hormonal reset. Yet no direct evidence for psilocybin or other similar psychedelics inhibiting fertility markers exist.
A potential mechanism for the immediate inhibition of motility could involve direct serotonergic signaling in sperm. Human sperm express multiple serotonin receptors, including 5-HT2A, and one recent study found that a 5-HT2A antagonist reduced sperm motility, suggesting that 5-HT2A may regulate motility. Psilocybin is known to bind 5-HT2A with high affinity.
