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LIVRAISON GRATUITE À PARTIR DE 65 € (NL)
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LIVRAISON GRATUITE À PARTIR DE 65 € (NL)
Last updated: 5 August 2026 · By the Junita® Lab Team
Read time: about 7 minutes
Conversations about ageing skin rarely start with wrinkles. They start with “it just doesn’t bounce back any more”, usually said while pressing a cheek with two fingers. What people mean is firmness, and firmness is the word the industry has made almost meaningless. This post is for the reader whose skin is doing two things at once: showing its age, and reacting to nearly everything sold to fix that. If your skin were robust, the standard advice (retinoid, acid, repeat) would be fine. If it is not, that advice tends to end in a stinging, flaking, oddly duller face.
Under the surface sits the dermis, a woven network of collagen and elastin built and maintained by cells called fibroblasts. Firmness, as you experience it, is largely the state of that network, and it thins with time. A classic study measuring forearm skin found skin collagen decreased with age and was lower in women at every age. Later work described a self-reinforcing part of this: fibroblasts in an aged, fragmented network get less mechanical stretch from the fibres around them, and fibroblasts that are not stretched make less new collagen. As the structure weakens, so do the cells meant to rebuild it.
The useful part is that “firming” on a label can mean three quite different things.
Some ingredients form a thin film that contracts slightly as it dries, giving a real but temporary sense of tightness. It is honest to say what it is not: it sits on your skin, it does not change the dermis, and it leaves when you cleanse. Caffeine Depuff Complex™, our eye cream, uses an algae-derived complex at 3% for exactly this.
Well-hydrated skin genuinely looks firmer, and lines caused by dehydration soften when water comes back. This is where hyaluronic acid lives, and where most copy goes vague, because hyaluronic acid is a family of molecules of very different sizes, and size decides where it can go. Researchers tracking it through excised human skin with Raman spectroscopy found low molecular weight forms (roughly 20 to 300 kDa) passed through the stratum corneum, while high molecular weight forms (roughly 1000 to 1400 kDa) did not. Neither is better, they do different jobs, but a label that only says “hyaluronic acid” is telling you less than it sounds like.
This is the slow one. Certain short peptides are fragments of the skin’s own structural proteins, and the “matrikine” idea holds that when fibroblasts meet these fragments they respond as though the network needs rebuilding. Tetrapeptide-21, the peptide we use, is one of them. The published work behind it showed increased collagen production in human dermal fibroblasts in the laboratory, and in a double-blind, randomised, placebo-controlled study in ten volunteers of average age 48. A separate arm measuring skin roughness in 30 volunteers by three-dimensional fringe projection found the peptide, and not the placebo, significantly reduced roughness. Ten volunteers is a small study, and it tested the ingredient rather than a Junita product.
Dermatology draws a clean line. Intrinsic, chronological ageing affects skin over the whole body, including places the sun has never reached. Extrinsic ageing is driven by chronic ultraviolet exposure, smoking and other pollutants, and is layered on top.
Ultraviolet is the biggest lever you control. A study of 298 Caucasian women aged 30 to 78, split by sun-seeking and sun-avoiding history and graded by trained assessors, concluded ultraviolet exposure appeared responsible for around 80% of visible facial ageing signs. That figure gets quoted everywhere without the detail that makes it useful: in the same study, pigmentation differences between the groups were strong at every age, while ptosis (the sagging quality of the lower face) tracked chronological ageing and did not differ meaningfully between them. Wrinkles were influenced by both. So sunscreen does enormous work on tone and marks, and rather less on the specific thing most people mean by firmness. The mechanism is well described: ultraviolet light prompts the skin to produce enzymes that break down collagen. Worth naming the limits of that figure: it is the authors’ own hedged conclusion, drawn from 298 Caucasian women, and the study was carried out by L’Oréal Research. We quote it because it is the best-known estimate, not because it settles the question.
Research measuring skin biopsies found collagen type I and type III were significantly lower in postmenopausal than premenopausal women, and correlated inversely with years since menopause. That explains a common experience: skin changing faster over two or three years than over the previous ten. It also has a limit we will not pretend around. A cream does not act on your hormones. If perimenopause or menopause is driving the change, that is a conversation for your GP. Ageing and menopause are normal, neither is a disease, and nothing in a jar treats either.
The standard escalation goes: exfoliate more, add a retinoid, increase the strength, add more actives. For robust skin that often works. For reactive skin it starts a loop that feels like failure but is really just irritation. What makes it confusing is that irritation does not always show. Dermatology recognises a form of irritant reaction called subjective or sensory irritation: itching, stinging, tingling or burning with no visible or histological sign of inflammation. So you can be told, sincerely, that your skin “looks fine” while it stings every evening. Your experience is real. It is simply not visible.
Retinoid tolerance is the clearest example. In a 12-week randomised, double-blind study, participants using retinol 0.5% reported more facial skin scaling and stinging than those using bakuchiol. Topical retinoids are effective and well established, and for many people early irritation settles. For reactive skin it often does not, and a gentler active you use for three months beats a stronger one you abandon in three weeks.
Then the loop closes. An over-worked barrier holds less water, so skin looks duller and rougher and dehydration lines become more obvious. That reads as ageing, so the routine gets pushed harder. This is why our approach is build before you brighten. Settle the barrier first, then judge what the actives are doing, because you cannot read results through irritation.
Everything below is at ingredient level, with the evidence named. Where we publish a percentage on the product page we have used it; where we do not, we have not invented one.
Bakuchiol is a plant-derived compound that is not structurally a retinoid but behaves in some similar ways. Gene expression profiling found broad overlap between the two in how they influenced skin gene expression, with upregulation of type I, III and IV collagen in cell models.
The trial worth knowing is a 12-week randomised, double-blind study in 44 people comparing bakuchiol 0.5% cream twice daily with retinol 0.5% cream daily, photographs analysed every four weeks and a blinded dermatologist grading pigmentation and redness. Both significantly decreased wrinkle surface area and hyperpigmentation, with no statistical difference between the compounds, and the retinol users reported more facial skin scaling and stinging. Two caveats we will not skip: that trial used 0.5% where Bakuchigen Serum™ uses 1%, and it tested its own formulation, not ours.
Vitamin C is among the most-studied antioxidants in skin, with recognised roles in antioxidant defence and normal collagen formation. The textbook form, L-ascorbic acid, is also the awkward one. It is water-soluble and unstable, oxidising on contact with light and air, and an oxidised formula is not doing the job you bought it for. It also only enters skin when the formula is more acidic than pH 3.5, considerably more acidic than the skin it sits on, and that acidity is a common reason vitamin C products sting. On robust skin, an inconvenience. On the skin this post is written for, a dealbreaker.
That is why we do not use L-ascorbic acid in our leave-on formulas. We use stable vitamin C derivatives instead: forms that hold together at a skin-friendlier pH. One of them, sodium ascorbyl phosphate, the form in our weekly mask, was tested in a 12-week randomised controlled trial and was as well tolerated as the placebo lotion it ran against. The honest trade-off, and there is one: L-ascorbic acid still carries the largest body of direct evidence, and how much vitamin C each derivative delivers into skin varies by form. For reactive skin we think stability and tolerance win that trade, and we would rather tell you the trade exists than pretend it does not.
Ferulic acid is the stability story’s other half. In a much-cited laboratory study, adding it to a solution of 15% L-ascorbic acid and 1% alpha-tocopherol (vitamin E) improved the vitamins’ chemical stability and doubled photoprotection against solar-simulated light, from roughly fourfold to roughly eightfold. Two honest caveats, because they matter. That work was done on pig skin, not living human skin, so read it as mechanism rather than as a result you should expect. And it tested that specific three-part system. Bakuchigen Serum™ pairs its vitamin C with ferulic acid at 2%, so it borrows the stabilising principle, but it is not that formula and it does not contain vitamin E. We do not publish the vitamin C percentage, so we are not stating one.
Tetrapeptide-21 appears at 2% in Tetrapeptic™ Day Cream, and further down the list in Bakuchigen Serum™ without a stated percentage. The same caveat applies here as with bakuchiol: the study above tested the peptide itself in ten volunteers and did not publish the concentration used, so nothing links that trial to our 2%. Read it as why the ingredient is in the formula, not as a result you should expect from it. Ectoin is not a firming ingredient and we will not dress it up as one. It is a small water-binding molecule made by microorganisms living in extreme environments, and its interest for us is resilience: in a randomised, comparator-controlled, double-blind trial in 65 adults with mild to moderate atopic dermatitis, an ectoine-containing cream was very well tolerated and performed equivalently to the comparator over 28 days. For reactive skin, the ingredient that lets you keep using the routine matters as much as the one doing the headline job.
A 12-week study applied 5% niacinamide to one half of the face and its vehicle to the other in 50 women with clinical signs of facial photoageing, double-blind and left-right randomised. It reported reductions in the appearance of fine lines and wrinkles, hyperpigmented spots, red blotchiness and sallowness, with improved elasticity measured by cutometry. Niacinamide is in Caffeine Depuff Complex™, though we do not publish its percentage there, so read that study as evidence for the ingredient rather than a claim about the product.
Caffeine is unusually well characterised for a cosmetic active. A review of its cosmetic use notes that commercial topical formulations normally contain 3%, that it has antioxidant properties, and that it increases microcirculation of blood in the skin. Caffeine Depuff Complex™, which is an eye cream rather than a face cream, uses 3%, alongside Euphrasia (eyebright) extract at 4%, which we include on the basis of long traditional use for tired eyes rather than a clinical evidence base. We would rather say that plainly.
Even tone reads as youthful skin at least as much as tautness does, which is why pigmentation was such a strong signal in the sun-exposure study. Azelaic acid is a gentle option there: a review describes anti-inflammatory, antioxidative and anti-keratinising effects with good tolerability across clinical trials. That review covers azelaic acid as used in prescription strengths of 15 to 20%, well above the 3% in our mask, so treat it as the direction of travel rather than as the same thing. Hyaluronic Drench Complex Mask™ contains it at 3%.
People spend years on facial ageing and then hold up a phone. Hands show it early, partly from sun and partly from something dermatology is unambiguous about: among all skin irritants, wet work is the most important. Repeated washing and sanitiser do steady, cumulative damage to the barrier, and thin, dehydrated hand skin looks crepey long before the face does. Keep a hand cream by the sink and use it every single time.
Look at the studies quoted here. The bakuchiol and retinol comparison ran 12 weeks. The niacinamide study ran 12 weeks. The ectoine trial ran 28 days. Nobody photographed anyone on day ten and declared a result. Comfort can change within days, because hydration moves fast. Tone and marks tend to shift over one to three months. Anything involving the collagen network is slower again, and needs consistency more than intensity.
Our Age Defy & Firm Confidence range. We quote only the percentages we publish and can stand behind, and where a product page and its ingredient list disagree we have left the figure out rather than repeat it. All are cosmetics, and all are best judged at twelve weeks. If your skin is reactive, patch test and add one product at a time.
Bakuchiol at 1% with a stable vitamin C and ferulic acid at 2%, plus rose damascena flower water, rosehip seed oil, sodium hyaluronate and Tetrapeptide-21. Allergy tested. It does contain perfume and naturally occurring fragrance components (limonene, linalool, geraniol), so check the ingredient list if you are fragrance-sensitive.
View productTetrapeptide-21 at 2%, with ectoin, a stable vitamin C (tetrahexyldecyl ascorbate), vitamin E, sodium hyaluronate and plant oils and butters. The slow, structural part of the routine. Do patch test: it includes menthol, camphor and eucalyptus oil, which some reactive skins do not enjoy.
View productCaffeine at 3%, an algae-derived tightening complex at 3%, Euphrasia (eyebright) extract at 4%, plus niacinamide, chamomile flower water and rosehip seed oil. The tightening is a temporary surface film; the niacinamide and caffeine work over weeks.
View productAzelaic acid at 3% with hydrolysed sodium hyaluronate, kojic acid, sodium ascorbyl phosphate, allantoin and cacay seed oil. A weekly treatment rather than a daily step, aimed at the evenness half of looking rested.
View productSodium PCA and sodium hyaluronate for water, shea and cupuaçu seed butters to hold it there, plus ectoin, allantoin, helichrysum flower water, argan oil and a stable vitamin C. Built for hands doing wet work, which is most hands. Do patch test: it contains bergamot oil and naturally occurring fragrance components including citral, limonene, linalool, geraniol and citronellol, which is worth knowing if your hands are already sore.
View productJunita® exists for difficult skin, and difficult skin ages too. It just cannot get there by the usual route. Our approach is to name the mechanism, name the percentage, and be honest about the size of the evidence, because the alternative is asking you to take our word for it. Build before you brighten. Then give it three months.
If you know someone who has been told the anti-ageing aisle is not for their skin, please pass this on.
Usually one of three things: a film-forming ingredient that tightens as it dries, which is immediate but temporary; a humectant such as hyaluronic acid that holds water in the upper skin, so dehydration lines soften; or a peptide that signals to fibroblasts over weeks. Only the third is aimed at the structural network, and it is the slowest and least certain of the three.
Usually because it out-paces what your barrier can handle. Over-worked skin holds less water, so it looks duller and rougher and fine lines become more visible, which reads as ageing and tempts you to push harder. Irritation is not always visible either: stinging with no redness is a recognised irritant reaction.
In a 12-week randomised, double-blind study of 44 people, bakuchiol 0.5% twice daily and retinol 0.5% daily both significantly decreased wrinkle surface area and hyperpigmentation with no statistical difference between them, and the retinol users reported more scaling and stinging. That is one trial of one formulation, so bakuchiol is fairly called a well-tolerated alternative rather than a proven equal in every case.
That figure comes from a study of 298 Caucasian women aged 30 to 78 comparing sun-seeking and sun-avoiding histories, which concluded ultraviolet exposure appeared responsible for around 80% of visible facial ageing signs. The detail matters: pigmentation was strongly tied to sun exposure, sagging tracked chronological age instead, and wrinkles were influenced by both.
Yes. Work using Raman spectroscopy found low molecular weight forms (around 20 to 300 kDa) passed through the stratum corneum, while high molecular weight forms (around 1000 to 1400 kDa) did not. Neither is superior, they do different jobs, but a label that only says “hyaluronic acid” is not telling you which.
It can support comfort, hydration, and the appearance of tone and texture. It cannot act on the hormonal change itself. Research measuring skin biopsies found collagen type I and III were significantly lower in postmenopausal than premenopausal women and correlated inversely with years since menopause. If that timeline matches yours, talk to your GP.
Comfort and hydration can change within days. Tone and marks generally take one to three months. Anything involving the collagen network is slower still. Most of the studies behind these ingredients ran twelve weeks, so that is the fairest point at which to judge a routine.
No, and any product claiming so is overstating what it can do. Ageing is a normal biological process, not a disease, and cosmetics work on the appearance and condition of the skin’s surface. Junita® products are cosmetics, not medical treatments.
Written by the Junita® Lab Team. Junita® is a skincare brand built for difficult, reactive skin, with a barrier-first, evidence-led philosophy. Founded in the Netherlands by June Kibera, who started formulating because nothing on the shelf worked for her own skin.
With love and science,
The Junita® Lab Team
Junita® products are cosmetics, not medical treatments. Ageing is a normal biological process, not a condition to be cured. Nothing here is medical advice. If something on your skin is changing, sore, or worrying you, please see a GP or a dermatologist.
