Peptides are short fragments of protein, chains of anywhere from 2 to 50 amino acids linked together. Inside the skin they act as messengers that tell it to make more collagen and elastin, the proteins behind firmness and bounce. The result is softer fine lines and skin that holds its shape a little better. They do not hit as hard as retinol. What they offer instead is barely any irritation, which makes them an easy anti-aging choice for almost any skin type.
The short version There are hundreds of peptides in skincare, and they sort into three broad jobs. Signal peptides nudge the skin to build collagen, carrier peptides ferry minerals into the skin, and inhibitory peptides ease the muscle signals behind expression lines. Matrixyl and Argireline are the two best known.
At a glance
Also known as
Peptides, Matrixyl, Argireline, Copper peptides, and more
Some peptides reach the deeper layer of skin (the dermis) and tap the cells that build collagen (the fibroblasts) on the shoulder. Signal peptides are the ones that do this best. The message is simple: make more collagen. Over time the skin plumps from within and fine lines look softer.
2. Softer expression lines
Inhibitory peptides like Argireline turn down the signal that travels from nerve to muscle, which slows the way repeated expressions etch themselves into the skin. Think of it as easing the pull of the muscles you use when you frown or smile. The lines settle in more slowly.
3. A stronger skin barrier
A few peptides such as palmitoyl pentapeptide help the skin make more of the proteins that build its protective wall. That lends a hand to a barrier that has worn thin and lost some of its strength.
4. Antioxidant and calming support
Some peptides neutralize the free radicals (oxidative stress) that push skin toward aging and bring a mild soothing effect along with it. They make a useful backup in heading off the kind of aging that sun exposure speeds up.
The three categories of peptides
Signal peptides
These are the peptides that send skin cells a "do this job" message. They are the most widely used of all the anti-aging peptides.
Matrixyl 3000 (Palmitoyl Tripeptide-1, Tetrapeptide-7) A well-studied anti-aging peptide with a solid track record for visible results.
Matrixyl Synthe'6 (Palmitoyl Tripeptide-38) Stimulates six proteins at once, all tied to the skin barrier and elasticity.
Carrier peptides
These shuttle minerals like copper and magnesium into the skin, where they help collagen along.
Copper peptide (Copper Peptide, GHK-Cu) Supports wound healing and renewal and kick-starts collagen, which makes it handy for managing scars.
Enzyme- and neurotransmitter-inhibiting peptides
These slow the pace at which expression lines form. The idea is that they gently quiet the signal heading toward the muscles you use to make expressions.
Argireline (Acetyl Hexapeptide-8) Dials down the signal to the expression muscles and softens lines on the forehead and around the eyes.
SYN-AKE A peptide modeled on the way snake venom acts, used to soften expression lines.
How do peptides actually work in the skin?
Because a peptide is a small fragment of protein, it acts as a messenger when the skin builds proteins of its own. When a signal peptide locks into the receptor on a skin cell, it flips on the order to make collagen or elastin.
This is not the same as smearing collagen on top and filling lines from the outside. Collagen molecules are far too big to sink in, while peptides are small enough to absorb well and prompt the skin to make its own collagen.
Retinol vs. peptides — which should you reach for?
Retinol: powerful, but it can irritate, leaves skin more sun-sensitive, and is off-limits during pregnancy. There is a fair bit to keep an eye on.
Peptides: gentler in effect, yet they barely irritate and stay fine through pregnancy, which suits just about any skin type.
The two do not fight, so used together they round each other out. Peptides and their knack for repair take the edge off the irritation retinol can cause. Just space them out rather than layering them at once. Retinol at night and peptides in the morning keeps things calmer.
Side effects and precautions
A very safe ingredient. Side effects and irritation are rare.
Allergies are very uncommon. Even so, a patch test the first time is a good idea.
Give vitamin C some space. A strongly acidic environment can break peptides down, so vitamin C in the morning and peptides at night is the easier split.
Copper peptides clash with vitamin C. Better not to use the two together.
In a topical product, peptides have the edge. Collagen molecules are too big to sink into the skin, while peptides absorb well and signal the skin to build its own collagen.
How are Matrixyl and Argireline different?
Matrixyl kick-starts collagen to smooth fine lines, while Argireline turns down the signal to the expression muscles and softens expression lines. They work in different ways, so they complement each other when you use them together.
Can sensitive skin use them?
Yes, and they are a good fit. Peptides barely irritate, which makes them a sensible first move into anti-aging for skin that struggles with retinol.
Are they safe during pregnancy?
Yes, they are very safe. When retinol is off the table during pregnancy, peptides are a common stand-in.
When will I see results?
Give it 8 to 12 weeks for fine lines and firmness and 4 to 8 weeks for softer expression lines. Peptides work more slowly than retinol, so give them a little time.
Do oral peptide supplements work?
Their effect on the skin is limited. Taken by mouth they get broken down in the gut into small amino acids before they are absorbed, so they do not act on the skin directly. For skincare, the topical route does more.
