iS Clinical Youth Serum
The Verdict
Youth Serum earns its place as a fast, layerable treatment for an immediate tightening feel alongside longer-term growth-factor support, and it's one of the few serums in the range iS Clinical positions as safe close to the eye area — provided you apply it sparingly.
iS Clinical Youth Serum | Anti-Ageing Serum | 30ml
£158.00
iS Clinical Youth Serum is a lightweight gel serum built around the brand's Extremozyme® technology and a bioidentical Copper Tripeptide-1 growth factor, giving an immediate tightening feel while working on longer-term firmness underneath. It suits all skin types, including sensitive and mature skin, and is positioned as suitable close to the eye area. Apply sparingly — over-applying is the main cause of pilling.
What it is
Youth Serum is a 30ml gel serum, part of iS Clinical's Youth line alongside Youth Complex and Youth Intensive Creme. It's built around Extremozyme® technology together with Copper Tripeptide-1, an encapsulated blend of Vitamins A, C and E, Centella Asiatica, and caffeine for a tightening, pore-refining effect. Unlike Active Serum, which relies on botanical acids for controlled exfoliation, Youth Serum doesn't exfoliate — it's a peptide and growth-factor formula for skin that wants firmness rather than resurfacing.
Texture and how it feels on skin
It's a lightweight gel, closer in feel to a fluid than a traditional serum, that absorbs almost immediately with a noticeable tightening sensation on application. Because it sits close to the skin without leaving residue, it layers well under makeup — but applied too thickly, a concentrated gel like this one can pill rather than absorb cleanly. See the application notes below.
Key ingredients
iS Clinical doesn't publish a full INCI list on the listing, so this is a summary of the named actives rather than an exhaustive deck:
| Ingredient | What it's for |
|---|---|
| Extremozyme® technology | Proprietary enzyme complex, included to help improve the appearance of skin affected by environmental stress |
| Copper Tripeptide-1 | A bioidentical growth-factor peptide, included to help improve the appearance of firmness |
| Vitamin A (encapsulated) | A time-released form, commonly formulated as Retinyl Palmitate, included to help improve the appearance of fine lines — see FAQs on how this differs from retinol |
| Vitamin E (encapsulated) | An antioxidant included for added environmental protection |
| Centella Asiatica | A soothing botanical extract, included to help calm the skin |
| Caffeine | Included alongside the peptide complex for its role in the tightening, pore-refining effect |
Who it suits
- Skin showing fine lines, loss of firmness or textural changes
- Sensitive or mature skin — iS Clinical states the formula suits all skin types
- Anyone wanting a fast-absorbing layer that sits well under makeup
- Those who want a peptide and growth-factor approach rather than acid-based resurfacing
Not the pick if you're after controlled exfoliation — Active Serum is built for that instead. Because it's concentrated, apply sparingly rather than reaching for a full pump.
How to use it without pilling
iS Clinical's own guidance is "less is more": apply a small amount and let it absorb fully before layering anything else, rather than using a full dose at once. Concentrated gel-peptide serums pill more readily than lighter formulas, so building up gradually over a few applications avoids product balling on the skin. iS Clinical states the formula has passed ocular irritancy testing and positions it as suitable close to the eye area — apply carefully around the orbital bone and avoid direct contact with the eyes.
Youth Serum vs Youth Complex, and where it fits in a routine
iS Clinical also sells Youth Complex, built around hyaluronic acid, fruit acid extracts and the same Copper Tripeptide-1. Youth Complex leans on fruit acids for controlled exfoliation and hydration, while Youth Serum gives an instant tightening feel with no exfoliating acids — see our Youth Complex review for the full comparison. In a routine, it sits well after cleansing and before Youth Intensive Creme, which seals in moisture in a cream format. See our round-up of the best iS Clinical serums for anti-ageing and the iS Clinical brand page for the wider range.
Our verdict
Youth Serum earns its place as a fast, layerable treatment for an immediate tightening feel alongside longer-term growth-factor support, and it's one of the few serums iS Clinical positions as safe close to the eye area. The trade-off is technique: it rewards a light hand, and applying too much is the main way to undermine an otherwise easy-to-wear serum.
FAQs
How do you use iS Clinical Youth Serum without pilling?
Apply a small amount — iS Clinical's guidance is "less is more" — and let it absorb before adding another layer. Building up gradually, rather than using a full pump at once, avoids the gel balling on the skin.
Can it be used around the eyes?
iS Clinical states the formula has passed ocular irritancy testing and positions it as suitable close to the eye area. Apply carefully around the orbital bone and avoid direct contact with the eyes.
Is it the same as Youth Complex?
No. They share Copper Tripeptide-1, but Youth Complex also contains fruit acid extracts for controlled exfoliation, while Youth Serum doesn't exfoliate at all.
Can I reapply it over makeup?
iS Clinical positions Youth Serum as suitable for reapplying over makeup, given its fast-absorbing, non-greasy finish. Apply sparingly to avoid disturbing makeup or causing product to pill.
Does it contain retinol?
Not free-acid retinol. It contains an encapsulated form of vitamin A, commonly formulated in iS Clinical products as Retinyl Palmitate — a gentler ester form rather than retinol itself.