Editor's note

Peptides are real. Short-chain amino acids that signal to fibroblasts, support barrier function, and in some cases deliver copper ions. The science is legitimate. The gap between the science and what is written on product packaging is where you will lose an afternoon.

Other ingredients

• Niacinamide
• Vitamin C
• Retinoids
• Chemical Exfoliants
• Ceramides
• Peptides
• Humectants vs Emollients
• The Brightening Pair
• SPF Filters

What peptides are — and what they are not

Peptides are short chains of amino acids — the building blocks of proteins including collagen and elastin. In skincare, they work primarily as signalling molecules. The category is real. Most individual products oversell their particular peptides.

Myth, meet fact

• Myth: All peptides work the same way. Fact: Signal, carrier, and neurotransmitter-inhibiting peptides do different things by different mechanisms.
• Myth: Peptides can replace retinoids. Fact: The evidence base for retinoids is orders of magnitude larger. Peptides complement, not replace.
• Myth: A high peptide concentration means a better product. Fact: Stability, penetration, and formulation matter as much as the amount.

The beginner's path

1. What peptides actually do in a skincare product (4 min)
2. Copper peptides — the most evidence-backed category (4 min)
3. Reading peptide product claims honestly (3 min)
4. Where peptides fit in a routine (3 min)
5. Peptides with retinoids — a compatible pair (4 min)

Format and cadence

Copper peptide serum PM is the best-evidenced option. Signal peptide serum for the long game. Peptide moisturiser for low-intensity daily use. Peptide eye cream PM for periorbital support.

Everything we've published on peptides

• Copper peptides — what the evidence says
• Signal peptides — finding the ones that work
• The peptide marketing problem
• Peptides vs retinoids — can one replace the other
• Palmitoyl pentapeptide-4 — the most studied signal peptide