What are peptides in skincare?

What do peptides actually do?

Amino acids are the building blocks of proteins. Peptides contain several amino acids joined together; cosmetic peptides typically contain two to eight. Some act as signals within the skin rather than simply adding more material to its surface. Collagen and elastin help give skin strength and flexibility, which explains why peptides appear in products aimed at signs of aging.12

Peptides can also have anti inflammatory effects. Persistent inflammation and oxidative stress can contribute to wrinkles, discoloration, dryness and dullness; peptides may help reduce some of those effects. They are an option for aging skin, not a required step in everyone's routine.1

Do peptides work, and how long do they take?

Topical peptides have clinical support for improving skin damaged by ultraviolet exposure, a process called photoaging. Controlled trials are part of that support, so peptides are not just an attractive theory. The useful question is whether a particular formula has demonstrated the improvement you want, rather than whether the category sounds impressive.23

Think in weeks to months. A trial of a moisturizer containing 3 parts per million of palmitoyl pentapeptide 4 found reduced fine lines and wrinkles over 12 weeks. Another trial using 5 parts per million found improvements in roughness, wrinkle volume and wrinkle depth after two and four months. These are examples of tested formulas, not a universal concentration to shop for.2

How do you choose a peptide product?

Getting peptides into skin is a formulation challenge: penetration can be poor, and enzymes in skin can break peptides down. Some peptides are modified with fatty components to improve their passage through the outer skin layer. A longer list of peptide names is not a substitute for a formula that delivers them.2

Look at the whole product, including its moisturizing ingredients, vitamins and exfoliants. Peptides are one component, not the entire explanation for how a cream performs, however much space they occupy on the packaging. Retinoids and hyaluronic acid are other effective options for aging skin and tend to cost less.1

How do you use a peptide mask?

Peptides are among the ingredients used in facial masks for signs of aging. Masks stay on skin long enough for active ingredients to absorb, but they remain an addition to your routine, not its replacement, despite briefly occupying most of your face.4

1. 1Test a new mask on small areas of skin before using it across your face.
2. 2Apply the mask gently with your fingertips.
3. 3Follow the label's contact time and frequency. Leaving a mask on longer or using it more often can cause irritation.
4. 4Wash the mask off immediately if you feel itching, burning or stinging.
5. 5Apply moisturizer after washing off the mask, and continue cleansing and protecting your skin from the sun.

What should sensitive skin watch for?

For a peptide mask, consider the other ingredients too. Fragrance and essential oils can cause irritation or allergies, and strong exfoliating ingredients can irritate sensitive skin. Avoid a mask that duplicates exfoliating ingredients already in your routine, particularly alongside retinol or acid products. A peptide mask is not a treatment for acne or eczema. See a dermatologist if your skin feels worse after using one.4