Polypeptides can best be understood as "small chemical compounds composed of short-chain amino acids, which are the building blocks of protein.Peptides tell your cells to produce more collagen: one of the major building blocks of the skin. So by applying them directly to your skin, you're telling your body it needs to make more collagen. Benefits of Polypeptides for Skin When used in cosmetic skin products, peptides fall into three main categories: signal peptides, carrier peptides, and those that inhibit nerve signals. By acting as messengers, signal peptides can trigger collagen synthesis, which then increases skin firmness. Reduces the appearance of fine lines: By stimulating collagen production, peptides can give your skin the impression of being plumper. Peptides help to rebuild collagen and preserve skin's youthful appearance. Strengthens skin barrier: When peptides help amp up your skin cells, they may also help improve your skin barrier. Locks in hydration: As you age, collagen production decreases, which also causes dehydration. When peptides help boost collagen production, it also boosts hydration. Aids in collagen production: When collagen breaks down, the peptides send a signal to our skin's cells, informing them to make more collagen to replace what we lose naturally as we get older. Has anti-inflammatory properties: Antioxidants found in peptides help calm and soothe your skin, leading to less inflammation. Helps make skin more firm: By signaling your cells to produce collagen, peptides help your skin become more firm. Smooths out complexion: With upped collagen production likely comes clearer, more even skin, too. Repairs damaged skin: Carrier peptides work to heal your skin from the inside out.