The Inside Story

How Peptides Ingredient Help Build Collagen for Firmer Skin

Peptides are among the most powerful tools we have to smooth wrinkles and restore firmness. Here's everything you need to know before incorporating the collagen-boosting ingredient into your skin-care routine.

By Dianna Mazzone Singh

July 13, 2021

Woman with glowing skin against colorful background

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Imagine having a direct line to your skin cells. "Hey, I'm starting to notice some fine lines between my brows," you might text them. "Can we start doubling-down on collagen production this week?" But since speed-dialing your skin cells probably isn't in the cards for at least a millennia, in the meantime, you might consider using peptide-infused skin care. Peptides function as tiny couriers to our skin cells, sending messages that enable them to communicate more efficiently.

That in mind — aside from plastic surgery or injectables — peptides are among the most powerful tools we have to help smooth wrinkles and restore firmness. If your interest is piqued, read on to learn what makes peptides work, and how you can reap the benefits.

What are peptides?

"Peptides are short chains of amino acids," says New York City-based board-certified dermatologist Cindy Bae, M.D., "with amino acids being the smallest unit of a protein." And protein — in the form of elastin, keratin, and, mostly, collagen — is what gives skin its structure and resilience.

Notably, since peptides are amino acids and not proteins in and of themselves, they — unlike, say, collagen — are able to penetrate the skin when applied topically. "There is a limit of the size that a particle can be for it to actually get absorbed through the stratum corneum — which is the very top layer of the top layer of our skin, called the epidermis — and then used biologically within the skin," says board-certified dermatologist Melanie Palm, M.D., who is based in San Diego, California.

Different lengths and arrangements of those teeny-tiny amino acid chains result in different types of peptides. And while they all work by communicating with our skin cells, they don't all get their point across by the same means.

What are the benefits of peptides for your skin?

Most peptides used in skin care can be categorized within a few buckets (signal, carrier, enzyme-inhibitor, and neurotransmitter-inhibitor) depending on how they work.

"Signal peptides trigger mechanisms that impact wound healing," says Dr. Bae. "This, in turn, activates fibroblasts in response to fragmented chains of elastin and collagen." As in, these types of peptides make your skin cells think there's been trauma. Your body then goes into repair-mode and stimulates elastin and collagen production — resulting in firmer, plumper skin.

Copper peptides are the most common type of carrier peptide, which help deliver trace elements to the skin. According to Dr. Bae, copper in particular "helps active wound healing pathways" which, in turn, stimulates collagen production. There's also evidence that copper peptides have an antioxidant effect, meaning they may help squash skin-damaging free radicals.

Enzyme-inhibitor peptides are perhaps the most forward: They interfere with the enzymes in your body that naturally degrade collagen over time. For most of us, that starts to happen at around age 20.

And last but not least, neurotransmitter-inhibitor peptides block the release of certain chemical messengers which help contract muscles, therefore producing a muscle relaxing effect that theoretically mimics that of botulinum toxin, according to Bae. Botulinum toxin being, of course, the scientific name for Botox. But to rival an injection, a topical cream or serum needs to penetrate the epidermis, dermis, and fat layer in order to truly relax the muscle. And while we know peptides are tiny enough to get through the outer layer of our skin, more research is needed to formulate neurotransmitter-inhibitor peptides that can permeate even more deeply.

That said, there are infinite possibilities when it comes to peptides, with many labs bio-engineering and trademarking their own — which is why it's difficult to tell you to seek out any one type in particular.

How should you use peptides in your skin-care routine?

By now, we hope we've painted a picture of just how powerful peptides can be, especially if you're looking to improve your skin's firmness. But as with most any skin-care ingredient, results come from continued, consistent use.

You'll typically find peptides in leave-on products — think moisturizers and serums versus cleansers. Most peptide-enriched products are touted as such on the front of the bottle, but you can check the ingredient list for words like "dipeptide," "tripeptide," and "hexapeptide" if you’re not sure. Many formulations utilize multiple forms of peptides in order to maximize the collagen-boosting benefits, or pair peptides with other ingredients that help support a healthy skin barrier. And the good news is, no matter your price range, there are plenty of options on the market.

We like the Neutrogena Rapid Firming Peptide Contour Lift Cream, which combines peptides with hydrators like squalane for extra hydration, along with Drunk Elephant's Protini Powerpeptide Resurfacing Serum, made with lactic acid to provide gentle exfoliation. For more of a splurge, the hyaluronic acid in Dr. Lara Devgan Scientific Beauty Peptide Eye Cream helps plump fine lines on contact, while peptides work over time.