Small building blocks with big promises — but different peptides do different things and the evidence varies.
What is it?
Peptides are short chains of amino acids. Skincare uses several types, including signal peptides, copper peptides and so-called neurotransmitter-inhibiting peptides. They should not be treated as one single ingredient with one single effect.
What can it help with?
Some peptide products have been studied for fine lines, hydration, elasticity and skin texture.
What does the research say?
Studies and systematic reviews suggest that some peptides may improve aspects of skin appearance, but results vary between peptide types and formulations. Many older studies are small or lack strong controls. Newer pooled evidence is promising, but the evidence remains less consistent than for established retinoids.
How to use it
Peptide serums are usually applied after cleansing and before moisturizer. Follow the product instructions because formulations vary considerably.
What can it be combined with?
Peptides generally pair well with moisturizers, hyaluronic acid, niacinamide and barrier-supporting skincare.
Who should be cautious?
Peptides themselves are often well tolerated, but the complete formulation may still contain ingredients that irritate sensitive skin.
GlowOver40 Take
Peptides are not a gimmick — but seeing “peptides” on the label is not enough to judge a product. The specific peptide, formulation and concentration matter.
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