Humanin

Humanin is one of the more biologically interesting longevity peptides on the board, and it lands at Neutral because fascinating biology cannot outrun an empty human file. It is a real, conserved, endogenous mitochondrial signal that declines with age, runs high in the children of centenarians, and carries a clean cytoprotective and insulin-sensitizing mechanism, per Yen 2020. For someone chasing neuroprotection or longevity insurance, the safety posture is reassuring and the mechanism is legitimate. The honest ceiling is hard: no human interventional trial of administered humanin exists, the largest human cohort tied high levels to worse outcomes in the oldest old, per Conte 2019, the marquee work leaned on the unapproved HNG analogue, and the only product available is grey-market research chemical. This is an experiment-if-you-must intervention, not a recommendation.

✅ Best for: Aging adults who find the mitochondrial-derived-peptide biology genuinely compelling and want to run a careful self-experiment with eyes open. Insulin-resistant individuals drawn to the central insulin-sensitizing mechanism shown in rodents, who will track fasting glucose and HbA1c rather than assume benefit. People with a low-endogenous-humanin profile, such as carriers of the humanin-region mtDNA SNP, who fit the most plausible responder description. Citizen-science-minded users who accept research-peptide risk, will log objective biomarkers, and treat humanin as a contribution to their own data rather than a proven therapy. Anyone who can independently verify source sterility, identity, and purity by certificate of analysis.

❌ Avoid if: You have active, recent, or suspected cancer, because chronically raising a pro-survival signal that engages the IGFBP-3 axis is a real theoretical concern even without confirming human data. You are pregnant or breastfeeding, since there is no safety data in those states. You want proven results, because no human interventional trial supports any humanin claim and the largest human cohort points in a conflicting direction. You cannot vet your source, since grey-market peptides carry genuine sterility, identity, and endotoxin risk that can exceed the molecule's own modest hazard. You would rather put limited budget toward a longevity lever with at least some human interventional evidence behind it.