Peptides are small parts of amino acids, which are the building blocks of proteins like keratin. While protein is critical for the healthy production of hormones and things like collagen and elastin, peptides are particularly potent as anti-aging fighters and skin restorers. They also have the ability to soothe and tighten skin, improve the appearance of wrinkles, and boost collagen production. Popular peptide ingredients include copper peptides, tripeptide, palmitoyl tetrapeptide and tripeptide, hexapeptides, myristoyl pentapeptide, and Sh-Oligopeptides.