What Are Peptides? Here's What to Know About This Popular Skincare Ingredient

Including when to use them—and when to avoid them.

From K-beauty brands like Dermafirm to drugstore staples like Olay, skincare products formulated with peptides are seemingly everywhere these days. But what exactly are peptides? Do they really improve the appearance and condition of skin or is this ingredient just another skincare fad? Considering trying a product with peptides? Here’s what you need to know.


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What Are Peptides?

According to Dr. Laura Purdy, spokesperson for Dermafirm, “Peptides are amino acids that are referred to as the building blocks of certain proteins needed by the skin, like collagen and elastin.”

Peptides are essential for the skin's structure and function, including firmness, texture, and overall appearance. They work by telling your body that it needs to heal. “In turn, this notifies the body to produce more collagen where it’s needed most. For example, if you have ever experienced an injury on a joint, the peptides will signal your body to focus its repair efforts on that specific targeted area." 

How Peptides Work

“Peptides stimulate collagen and elastin fibers in our bodies which naturally decline with aging. By regularly applying a product with anti-aging peptides in it, you will be helping your body to build new collagen, thus making your skin appear plumper and firmer," explains Georgia Smith, cosmetic chemist and founder of Skin Sister.

Peptides can also help diminish redness, ease inflammation, and help skin look plumper. All of this makes the appearance of wrinkles less obvious, explains Purdy. “When peptides are formulated into skincare, those products improve tissue repair and cell turnover and help prevent and treat the overall signs of aging.”

Should You Incorporate Peptides Into Your Skincare Routine?

Both Smith and Purdy believe most people can benefit from using products formulated with peptides, especially those over the age of 30, because that’s when the body’s natural supply of collagen starts to deplete. “It’s best to start using these sorts of products around then or earlier if you start to notice fine lines forming," Smith says.

However, some under 30 may also want to consider products formulated with peptides. Smith tells me, “Teens with acne or who [have] breakout-prone skin can benefit from peptides.”

Should Peptides Ever Be Avoided?

Apply the same rule with peptides that you would with any other skincare product or ingredient. If something irritates your skin or causes you to break out in acne or a rash—you shouldn’t use it. Purdy always suggests doing a patch test to avoid any major problems, especially for those with sensitive skin. However, peptides are not a particularly irritating ingredient for most people. 

Purdy also says it's best to avoid combining direct acids with peptides. “This is because of the susceptibility of peptides to hydrolysis, which breaks the bonds between peptides—reducing their efficacy and making them into individual amino acids.” For the best results, double-check the ingredients in your current skincare regimen before adding a product with peptides.

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  1. Jeong S, Yoon S, Kim S, et al. Anti-wrinkle benefits of peptides complex stimulating skin basement membrane proteins expressionInt J Mol Sci. 2019;21(1):73. doi:10.3390/ijms21010073

  2. Skibska A, Perlikowska R. Signal peptides - promising ingredients in cosmeticsCurr Protein Pept Sci. 2021;22(10):716-728. doi:10.2174/1389203722666210812121129

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