Epithalon (also spelled Epitalon) is a small synthetic peptide of four amino acids, developed in Russia from a pineal gland extract. Lab studies show it can switch on telomerase, the enzyme that protects the ends of chromosomes, and small human studies suggest it may help restore melatonin rhythm in older adults. Most of the research comes from one group, and there is no proof that it extends human life. It is best seen as an experimental longevity option, used with a physician and alongside proven habits.