I respect Christin’s opinions on these sort of things given her background and focus on aging and cognition.
A review of popular peptides including GLP1-RAs, SS-31, BPC-157, and Cerebrolysin
The global peptide therapeutics market was estimated at a whopping $117B in 2024 and is continuing to grow. The leading edge of that market is driven by popular peptides in use by biohackers and longevity enthusiasts that range from the off-label use of GLP-1 agonists for Alzheimer’s prevention, to the newly FDA-approved mitochondrial therapeutic SS-31 (elamipretide), to popular grey market biohacker compounds like BPC-157 and Cerebrolysin.
Eventually some of these peptides will be proven to be effective and safe by the US FDA for cognitive enhancement and dementia prevention and will become part of everyday household use for Americans.
Here I review what we know about them now.
My Take
I personally err on the side of caution for myself given that I am relatively young and doing pretty well with my cognition and brain aging. The only peptide that I take amongst these is a microdose of a GLP1-RA (0.5mg of Semaglutide). This is because of its FDA approval and 10+ year safety profile as well as multiple proven benefits for metabolism and cardiovascular risk with speculative/accumulating evidence for dementia prevention. No other peptide meets my own criteria for risk/benefit tradeoff.
Other people may make different choices according to their risk tolerance and need for quicker solutions to stave off or treat cognitive decline/dementia.
The Risks
Translation Gap: From Mice to Humans
A persistent challenge across peptide research is the failure of dramatic rodent results to replicate in humans with only 1.5% of positive mouse studies translating to FDA approved therapeutics. That rate is even worse for brain therapeutics with many failing not just for efficacy but also for safety (>20% of trials). Compounds showing 10-fold improvements in maze learning or complete reversal of cognitive deficits in mice consistently fail to demonstrate meaningful clinical benefit. The reasons are multifaceted: rodent models of neurodegeneration imperfectly recapitulate human disease; most preclinical studies use young adult animals rather than aged subjects with accumulated pathology; and the pharmacokinetics of peptide delivery to the brain differ substantially between species. Dihexa’s trajectory—from claims of being “seven orders of magnitude more potent than BDNF” in rodents to a failed Phase 2/3 trial and retracted foundational research—exemplifies this “valley of death.” This pattern demands particular caution when extrapolating from compelling animal data to expectations for human cognitive benefit.
Purity, Source, and Drug-Drug Interactions
Risks also include those related to purity and source in grey market-obtained peptides. The hospitalization/near fatal incidents of two attendees who were given peptides at RAADFEST (Revolution Against Aging and Death Festival), a longevity biohacker conference in Vegas, exemplifies those additional risks. Those two individuals were notably taking multiple peptides at once. Combining multiple peptides together represents additional risks from unknown/untested drug-drug interactions.
Read the full article: Peptides for Cognitive Enhancement & Dementia Prevention