What are Epitalon and Thymalin and what are their anti-aging claims?

Epitalon and Thymalin are synthetic peptides developed in Russia with purported anti-aging properties. Epitalon (also spelled Epithalon) is a tetrapeptide that mimics epithalamin, a pineal gland peptide. Proposed mechanisms include telomerase activation (potentially lengthening telomeres), melatonin regulation, and antioxidant effects. Russian studies suggest improved sleep, reduced mortality in elderly populations, and biomarker improvements, though Western replication is limited. Thymalin is a thymus peptide complex that may support immune function and counteract thymic involution with age. Both peptides are central to certain anti-aging protocols. However, human clinical data from rigorous Western trials is scarce, and most evidence comes from Russian research with methodological limitations. Neither peptide is FDA-approved or widely accepted in conventional medicine. They're primarily used in anti-aging and biohacking communities. Quality sourcing is challenging, and long-term safety data is essentially absent despite decades of use in research contexts.