By Dr Naomi Mackle
Dermatology Specialist and Medical Director, Adare Dermatology Clinics
Peptides are everywhere right now. Serums, eye creams, and moisturisers promise that these “signalling” ingredients will prompt your skin to produce more collagen, smooth wrinkles, and even rival injectables. It is one of the biggest buzzwords in skincare—and many brands have jumped on the bandwagon.
As a dermatology specialist-led brand, REFORM Skincare’s approach is to look honestly at the evidence rather than the marketing hype. The central question is simple: do peptides really work for anti-ageing?
Here is what the research shows, where its limits lie, and why we have chosen other ingredients for our formulations.
The Bottom Line
Peptides may well have a place in skincare, but the current evidence is weak, so our position is to watch this space. Before choosing any product, be clear about what you are trying to achieve. For fine lines, wrinkles, pigmentation, or redness, there are already highly effective, proven ingredients available.
It is also important to understand that every topical product—even the best ones—has limits. Skincare makes a real difference and helps maintain treatment results, but if you want to look your best as you get older, you will still need clinical treatments such as medical microneedling, radiofrequency microneedling, and lasers, along with anti-wrinkle injections or fillers where appropriate.
What Are Peptides and What Do They Claim to Do?
Peptides are short chains of amino acids—the fundamental building blocks of proteins such as collagen and elastin. In skincare, they are included on the theory that they can send signals to skin cells, triggering repair and renewal.
Cosmetic peptides are typically grouped into four main types:
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Signal peptides (e.g. palmitoyl pentapeptide-4): Claim to stimulate collagen synthesis.
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Carrier peptides (e.g. copper peptides / GHK-Cu): Deliver trace minerals involved in wound healing.
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Neurotransmitter-inhibiting peptides (e.g. acetyl hexapeptide-8): Marketed as a topical alternative to anti-wrinkle injections.
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Enzyme-inhibiting peptides: Claim to slow down the natural breakdown of collagen.
Peptides are also increasingly promoted for barrier repair and skin hydration.
What the Evidence Actually Shows
Peptides are not a fantasy ingredient. Laboratory research demonstrates that certain peptides can influence skin cells in a dish, and a handful of clinical studies report modest improvements in the appearance of fine lines. However, a closer look reveals critical limitations:
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Penetration is a real hurdle: Peptides are relatively large molecules, and the skin barrier is designed specifically to keep such molecules out. Whether an active peptide reaches the living layers of the skin in sufficient quantities to alter collagen production remains uncertain.
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Studies are small and brief: Many trials involve small participant groups, last only a few weeks, and are funded by the ingredient manufacturers themselves. Independent, long-term studies are scarce.
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Results are subtle: Where improvements do occur, they are generally modest—and often comparable to what a good moisturiser achieves simply by hydrating the skin.
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The "injectable in a jar" claim fails: There is no convincing evidence that a topical peptide relaxes facial muscles in the way anti-wrinkle injections do.
More broadly, it is questionable whether any topical product can meaningfully stimulate new collagen. By contrast, the evidence for daily sunscreen, L-ascorbic acid (vitamin C), and retinoids in preventing and improving photo-ageing is robust, consistent, and built over decades.
Who Peptides Suit (and Who Should Be Cautious)
Peptides are generally well tolerated, meaning they suit almost anyone. Irritation is uncommon, which is why they are frequently marketed to sensitive skin types.
The primary caution is not about safety, but about expectations and value. Because peptides are a major trend, there is a real risk they have been oversold. If you are paying a premium for a peptide product—or using it in place of ingredients with a stronger track record—you may be spending money on hope rather than evidence.
That does not mean peptides do not work at all; it means we do not yet know how well they work.
Why REFORM Skincare Doesn't Use Peptides (Yet)
I am not anti-peptide. I simply do not believe the evidence is compelling enough yet—either in topical skincare or in the injectable peptide treatments gaining popularity.
Our formulations rely on well-established ingredients with proven efficacy:
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Core Actives: L-ascorbic acid, broad-spectrum sunscreen, retinol, hyaluronic acid, and niacinamide have well-documented roles in hydrating, restoring the skin barrier, and improving photo-ageing, redness, and pigmentation.
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Targeted Barrier Repair: Rather than peptides, REFORM utilises hyaluronic acid, niacinamide, our Vitamin B5 Gel, Phytobotanical Gel, and a dedicated Skin Barrier Repair Cream formulated with a high percentage of urea and lactic acid.
Our Approach to Retinoids
One argument for peptides is that they offer a gentler alternative to retinol. REFORM addresses sensitivity differently: our retinoid uses 1% retinyl palmitate, a very gentle retinol ester that can be applied nightly to the face, neck, and eye area without irritation. Consistent, well-tolerated use over time yields far better long-term results than short bursts of a harsh product.
Conversely, I am cautious regarding prescription tretinoin. In my experience, it frequently compromises the skin barrier. If you require active resurfacing, it is far better to visit a clinic for a targeted CO2 laser or TCA peel rather than enduring persistent, low-level peeling at home.
How to Introduce Peptides Safely
If you still wish to try a peptide product, doing so is straightforward:
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Application: Peptides can be introduced into your routine daily from the start.
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Compatibility: There are no well-established skincare ingredients that conflict with peptides.
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Safety: Patch testing is not routinely required, though you should discontinue use if irritation occurs.
The Golden Rule: Use peptide products alongside, never instead of, the essential foundations: daily broad-spectrum sunscreen, an antioxidant (such as vitamin C) in the morning, and a gentle retinoid at night.
If you would like tailored advice on the right combination of skincare and clinical treatments for your skin, you can book a consultation at Adare Dermatology Clinics in Dublin, Limerick, or London.
