The research behind our Peptide Anti-Ageing Serum

What peptides are, what hexapeptide-11 really does, how a peptide serum compares with retinol, and what the research does and doesn't prove.

Peptide serums have become the gentle alternative to retinol: no flaking, no nights off, nothing to build up to. That's all true. What's less often said is how much the evidence varies from one peptide to the next, and how little of it comes from independent researchers.

This guide explains what peptides are, then goes through our Peptide Anti-Ageing Serum one ingredient at a time. If you only want the product, the serum page has everything in one place.

01What peptides are

Proteins such as collagen and elastin are long chains of amino acids. Peptides are short ones, usually between two and a few dozen amino acids long. Your skin makes and breaks down peptides all the time, and some of the fragments act as messages between cells: signals that something needs repairing or rebuilding.

Cosmetic peptides are designed to borrow that language. The idea is that a small, well-chosen peptide applied to the skin can prompt cells to do more of a useful job. Because they're gentle and don't act like vitamin A, they suit people whose skin doesn't tolerate retinoids, and they can be used morning and night.

The catch is that peptides are very different from one another. A result for one peptide tells you nothing about another, and many are studied mainly by the companies that make them. So the only honest way to judge a peptide serum is peptide by peptide.

02The main types of cosmetic peptides

Hexapeptide-11 sits in the last group. It's studied less for building collagen directly and more for helping skin cells keep themselves in good working order, which is a newer and more modest idea.

03Peptides vs retinol

Retinol has far more evidence. If your skin tolerates it, it's the stronger choice for lines, and our retinol guide explains how to use it well. You can also use both: the peptide serum in the morning, retinol at night.

04How we rate the evidence

None of these studies tested our serum. It doesn't have its own consumer testing yet, so we don't show results for it.

05Hexapeptide-11

Hexapeptide-11 is a six-amino-acid peptide (phenylalanine, valine, alanine, proline, phenylalanine, proline) first isolated from yeast and now made to high purity. It's the hero of the serum.

06Ginkgo biloba

Ginkgo is one of the oldest tree species on Earth, and its fan-shaped leaves are rich in flavonoids and terpenoids, antioxidants that have been studied widely in the lab. The serum contains 1% ginkgo leaf extract. We found no human trial of ginkgo applied to the face at this level in a serum, so we describe it as a supporting antioxidant rather than a headline active.

07Hyaluronic acid

08Sodium PCA

PCA is the largest single part of the skin's natural moisturising factor, the mix of small molecules that holds water in the outer layer. A 1981 review (Clar and Fourtanier) found creams with at least 2% PCA or PCA salt improved dry skin in short and long-term use. It is an older review, much of it the authors' own work, and our percentage isn't published. There's more in the research behind our moisturiser.

09Dipalmitoyl hydroxyproline

An oil-soluble form of hydroxyproline, an amino acid found in the skin's supporting structure. Its maker reports firmer-looking skin and fewer visible wrinkles against placebo but hasn't published the study details, and we found no independent, peer-reviewed human trial. We list it as supporting: promising, not proven.

The serum also contains phytosterols and glycolipids, plant lipids that add comfort, and strawberry and blueberry seed oils, light oils rich in omega fatty acids.

10Aloe, the base

Aloe leaf juice is the first ingredient, so it's the largest single part of the formula; it replaces plain water as the base. In a two-week study of 20 women (Dal'Belo et al., 2006), creams containing freeze-dried aloe raised the water content of the skin's outer layer. It was a small forearm study and says nothing about lines.

11The peach tint

The serum has a soft peach tint from iron oxides (CI 77491), pure mineral pigments. It's there for colour and a subtle warmth on application, not as a treatment. We mention it because a tinted serum sometimes surprises people the first time they use it.

12What to layer it with

The serum goes on first, on clean skin. Follow with a moisturiser: our Anti-Age Day Cream in the morning and our Collagen Anti-Age Night Cream in the evening are designed to sit on top. Around the eyes, add our Smoothing Eye Cream. If you prefer everything together, the serum and day cream come as the Anti-Ageing Performance Duo, and with the eye cream as the Anti-Ageing Collection Box.

It works alongside most other actives. If you use retinol, keep it to the evening and use the peptide serum in the morning. If you use a strong acid exfoliant, apply it on a different evening.

13How skin ages, in brief

Visible skin ageing has two drivers. Intrinsic ageing is the slow, genetic part: from our mid-twenties, skin gradually makes less collagen and elastin, holds less water and renews its surface more slowly. Extrinsic ageing is everything the outside world adds, and sunlight is by far the biggest part of it, followed by pollution and smoking. Together they show up as fine lines, a looser feel, uneven tone and dryness.

Skincare can't stop intrinsic ageing. What it can do is keep skin well hydrated, protect it from the sun, and, with the right actives, support the skin's own maintenance. Peptides are one of the gentler ways to try the last of those.

14Why skin cells' maintenance matters

Every cell constantly makes proteins, checks them and clears away damaged ones. Scientists call this system proteostasis, and its main tools include the proteasome, which breaks down worn-out proteins, and autophagy, the cell's recycling process. As cells age, these systems slow down, and damaged proteins build up. That's one of the reasons older cells work less well.

Hexapeptide-11 is interesting because the research on it focuses on exactly these systems. In the lab, it switched them on and helped cells cope with oxidative stress. That's a different idea from peptides that are meant to 'boost collagen' directly, and a more modest one. Whether it translates into visible change on a face over months hasn't been shown in a controlled trial.

15Common peptide myths

16Morning and evening with a peptide serum

Because hexapeptide-11 isn't light-sensitive and doesn't irritate like retinol, you can use the serum twice a day. In the morning it goes under your day cream and sunscreen; in the evening, under a richer night cream. If you already use retinol, a simple split works well: peptide serum in the morning, retinol at night, and a good moisturiser both times. Introduce one new product at a time, a week apart, so you know how your skin responds to each.

17What to expect, week by week

These are typical timelines for a hydrating peptide serum, not results from testing on our formula, which doesn't have consumer testing yet. Skin renews its surface roughly every four to six weeks, which is why texture and lines take longer than hydration.

18How to read a peptide serum label

Ingredients are listed in descending order of amount, down to 1%; below that, they can appear in any order. Hexapeptide-11 sits 17th in our list, which is typical: active peptides are used in small amounts, and a very high position on a label would be unusual. That's also why we explain the 2%: it describes the peptide ingredient as supplied, which is mostly water or glycerin carrying a small amount of peptide.

Look past the word 'peptide' on the front of the pack and find the named peptide in the INCI. If it isn't named, or appears after the preservatives and fragrance allergens, there's probably very little of it.

19For men, and for every skin tone

There's nothing gendered about peptides or hyaluronic acid. The serum's light, fast-absorbing texture suits anyone, including after shaving, once any stinging has passed. Its soft peach tint is subtle and doesn't show on the skin once it's absorbed.

20Keeping it fresh

Store the serum somewhere cool and away from direct sunlight. It doesn't need a fridge, though some people like the cooling feel. The pump keeps air and fingers out of the bottle; use it within the period after opening printed on the pack.

21How to choose a peptide serum

22How to use it

Smooth two pumps over face and neck and give it a minute to settle before moisturiser. A 30 ml bottle lasts around two months used twice a day. Give it eight to twelve weeks before judging it on fine lines.

23Who it suits

It suits you if retinol irritated you; your skin is normal or dry; you want a serum you can use morning and night; or you want every ingredient named. Skip it, or check first, if you need fragrance-free; you want the best-evidenced option for lines regardless of comfort; or you're pregnant and haven't asked your doctor.

24What it adds up to

This is a gentle, well-built peptide serum. Its hydration evidence is strong, its hero peptide has a plausible mechanism and an early elasticity result, and we've been clear about what the 2% means. If you want an anti-ageing serum with no adjustment period that you can use every morning and night, this is the one we'd point you to.

Start with the serum on its own for a week or two, under your usual moisturiser, so you know how your skin responds. Then build around it if you want to: a day cream in the morning, a richer cream at night, an eye cream for the thinnest skin. Keep the serum as the constant, and judge the results at twelve weeks rather than twelve days.

Not sure which routine suits you? Which anti-ageing routine is right for you? compares our options.

25Your questions, answered

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