If you’re not yet using peptides in your skincare routine, you’ve been missing out on one of the most game-changing trends to hit the beauty world. These amino acid-based snippets of skin-saving protein work like mighty messengers that positively influence cells and tissues to perform a full spectrum of essential functions.

Depending on how they’re configured, peptides can be either linear or cyclic. Linear peptides have one or more amino acids that link together, while cyclic ones have two ends joined together to form a circle, like insulin or the hormone IGF-1 (insulin-like growth factor 1). Both types of peptides work as signaling molecules and act as powerful antioxidants.

The most common peptides are collagen peptides, which help to stimulate healthy cell production and restructure skin to reduce fine lines, wrinkles, melasma, and more. Copper peptides are also popular and can decrease inflammation, boost the appearance of hair follicles, and increase skin firmness.

While peptides are great for all skin types, they’re especially good for those looking to decrease fine lines and wrinkles, make their complexion look more taut, and soothe inflammation or redness. “Peptides can also promote the growth of glycosaminoglycans, which are a family of carbohydrates that support the maintenance of collagen,” says Dr. Downie.

To maximize the results of peptides, it’s best to apply them in a serum or moisturizer that will have prolonged contact with the skin, as opposed to a cleanser or peel. You’ll also want to avoid exfoliating your skin immediately before or after using products with peptides, as this can reduce their efficacy.