Hyaluronic Acid in Skincare: What the Evidence Shows – Evigrade

Q: What works by the evidence?

Cosmetic HA delivers three reproducible effects: Surface hydration. A double-blind trial by Pavicic et al. (Journal of Drugs in Dermatology 2011) in 76 women showed a significant increase in stratum corneum water content after 8 weeks of 0.1% HA cream versus placebo. Reduction of fine line depth. In the same trial, lines up to 0.2 mm deep visually softened by 10–20% because the hydrated stratum corneum swells and temporarily smooths surface relief. The effect disappears within 24–48 hours of stopping use. Support after invasive procedures. Kerscher et al. (Dermatologic Surgery 2008) showed faster skin recovery after fractional laser in patients using HA cream. The film-forming effect cuts water loss during the wound phase. All three effects are real but temporary. They improve how skin looks for the next few hours without changing its structure.

Q: What does not work and why brands write it anyway?

Marketing claims that the evidence does not support: • "Restores skin elasticity". Elasticity comes from the dermal collagen scaffold and elastin fibres, not from stratum corneum hydration. Topical HA does not reach there. • "Stimulates your own collagen". This effect has been demonstrated only for injectable fillers, and as a response to mechanical tissue stretch and a foreign body (Wang et al., Archives of Dermatology 2007). No such mechanism applies to a cream. • "Replaces injections". Penetration depth, volume delivered, and duration differ by orders of magnitude. One millilitre of filler is 20 mg of cross-linked HA placed directly in the dermis. There is no cream equivalent. • "Lifts the contour". Mid-face descent comes from loss of subcutaneous fat volume and laxity of retaining ligaments. A topical humectant has no influence on either. The marketing exists for one reason: injectable HA works powerfully and visibly, and skincare brands borrow the association built by aesthetic medicine.

Q: Who actually benefits, who does not?

Topical HA delivers real benefit for: • dry and dehydrated skin – through surface water retention; • skin recovering from fractional laser, professional cleansing, or chemical peels – faster recovery; • mature skin combined with an occlusive – temporary smoothing of fine surface lines. It is unlikely to help if the goal is: • volumetric correction (that is the territory of fillers); • treating acne (azelaic acid, retinoids, benzoyl peroxide); • pigmentation lightening (azelaic, vitamin C, kojic acid, hydroquinone); • managing rosacea redness (brimonidine, rutin, azelaic 15%). For oily skin without dehydration signs, an HA-heavy cream is overkill – a light serum or gel format does the job.

TL;DR

Hyaluronic acid in creams and serums works only on the surface of the stratum corneum. It does not "penetrate the deeper layers of the dermis" – the molecule is too large to cross the epidermis. The useful effect is limited to temporary water retention in the top 30–50 microns of skin and a small optical smoothing of fine lines. Promises of "rejuvenation from within", "restoring turgor", or "the same result as injections" belong to marketing, not to the evidence base. Real volumising effect comes only from injectable HA – fillers and biorevitalisation. That is no longer skincare; it is a medical procedure with a different risk profile.

What hyaluronic acid is and what it does in skin

Hyaluronic acid is a polysaccharide built from repeating units of glucuronic acid and N-acetylglucosamine. The body produces it in synovial fluid, vitreous humour of the eye, and the extracellular matrix of skin. In the dermis HA holds water, supports turgor, and helps fibroblasts migrate during wound healing.

With age, skin HA content drops: by 50 it sits at roughly half the level of a twenty-year-old. That fact underpins the entire marketing narrative around HA in cosmetics: if there is less of it, surely topping it up from the outside should help. The logic sounds tidy but ignores the central obstacle – the barrier function of the stratum corneum.

A hyaluronic acid molecule weighs anywhere from 10,000 to 4,000,000 daltons. The epidermis lets through molecules up to about 500 daltons, and even that with caveats. Between the jar of cream and the actual dermis stands a barrier that classic hyaluronic acid simply cannot cross.

Molecular size matters – just not the way the label says

Manufacturers know about the barrier and worked around it with marketing language: "low-molecular-weight hyaluronic acid". You see numbers on the packaging: 50 kDa, 20 kDa, 5 kDa. The implication is that smaller mass means deeper penetration and stronger effect.

The evidence is more nuanced.

Low molecular weight (under 50 kDa) does penetrate the upper epidermis – deeper than high molecular weight HA. But this fraction has been associated with pro-inflammatory activity in research, because HA fragments signal tissue damage to immune cells (Jiang et al., Physiological Reviews 2011). Long-term use of low-molecular HA in people with sensitive or rosacea-prone skin theoretically sustains low-grade inflammation.

High molecular weight (above 1000 kDa) does not go past the stratum corneum but forms a film on the skin that holds water and reduces transepidermal water loss (TEWL). It is responsible for the immediate plumped look right after application.

Mid-range (50–1000 kDa) is the compromise: part stays on the surface, part penetrates the upper epidermis, the pro-inflammatory risk is lower.

None of these fractions reaches dermal fibroblasts and none of them stimulates endogenous HA synthesis. Marketing claims along the lines of "activates production" are not evidence-based.

Source: Bukhari SNA et al. Hyaluronic acid, a promising skin rejuvenating biomedicine. International Journal of Biological Macromolecules 2018;120(Pt B):1682–1695.

What works by the evidence

Cosmetic HA delivers three reproducible effects:

Surface hydration. A double-blind trial by Pavicic et al. (Journal of Drugs in Dermatology 2011) in 76 women showed a significant increase in stratum corneum water content after 8 weeks of 0.1% HA cream versus placebo.
Reduction of fine line depth. In the same trial, lines up to 0.2 mm deep visually softened by 10–20% because the hydrated stratum corneum swells and temporarily smooths surface relief. The effect disappears within 24–48 hours of stopping use.
Support after invasive procedures. Kerscher et al. (Dermatologic Surgery 2008) showed faster skin recovery after fractional laser in patients using HA cream. The film-forming effect cuts water loss during the wound phase.

All three effects are real but temporary. They improve how skin looks for the next few hours without changing its structure.

What does not work and why brands write it anyway

Marketing claims that the evidence does not support:

"Restores skin elasticity". Elasticity comes from the dermal collagen scaffold and elastin fibres, not from stratum corneum hydration. Topical HA does not reach there.
"Stimulates your own collagen". This effect has been demonstrated only for injectable fillers, and as a response to mechanical tissue stretch and a foreign body (Wang et al., Archives of Dermatology 2007). No such mechanism applies to a cream.
"Replaces injections". Penetration depth, volume delivered, and duration differ by orders of magnitude. One millilitre of filler is 20 mg of cross-linked HA placed directly in the dermis. There is no cream equivalent.
"Lifts the contour". Mid-face descent comes from loss of subcutaneous fat volume and laxity of retaining ligaments. A topical humectant has no influence on either.

The marketing exists for one reason: injectable HA works powerfully and visibly, and skincare brands borrow the association built by aesthetic medicine.

Injectable HA is a different story

Fillers and biorevitalisation do not depend on crossing the skin barrier. They work because they are injected directly into the dermis or subcutaneous tissue. Different products, different goals.

Fillers (Juvederm, Restylane, Belotero, etc.) are cross-linked HA that creates volume in a chosen zone: lips, cheekbones, nasolabial folds. Effect lasts 6–18 months depending on cross-linking density and area. Evidence base – dozens of RCTs and decades of practice; the safety profile is well characterised.

Biorevitalisation uses non-cross-linked or weakly cross-linked HA delivered by microinjections into the dermis. The aim is hydration and fibroblast stimulation through microtrauma, not volume. Evidence is thinner than for fillers; results are less predictable.

Risks of injectable HA: vascular embolism with tissue necrosis or blindness if the injection lands in an artery (rare but documented), biofilms, granulomas, filler migration. The procedure is medical, performed by a physician trained in emergency response and equipped with hyaluronidase to dissolve the filler if needed.

None of this applies to topical HA. No injection-grade benefit, no injection-grade risk.

What to look for on the label

INCI name – Sodium Hyaluronate (the sodium salt, more stable in cosmetic formulas) or Hyaluronic Acid. Derivatives:

Hydrolyzed Hyaluronic Acid – hydrolysed, low molecular weight.
Sodium Acetylated Hyaluronate – acetylated, more resistant to enzymatic degradation on skin.
Sodium Hyaluronate Crosspolymer – cross-linked polymer for prolonged moisture retention.

Formulas marketed as "deep action" usually combine several molecular weights. That is reasonable formulating, but it does not change real penetration depth.

Concentrations in creams typically sit between 0.1 and 2%. Above 2% the formula becomes sticky and difficult to use. The exact concentration is rarely on the label – brands disclose only the presence of the ingredient.

How to apply and what to layer

The key rule: hyaluronic acid works only in a humid environment. Applied to dry skin in dry air, the film actually pulls water from the deeper epidermis upward and outward – the opposite of the intended effect. So:

Cleanse.
Apply HA on damp skin – within 10–20 seconds of cleansing.
Layer an occlusive on top (dimethicone, squalane, lanolin, petrolatum). The occlusive locks in the water HA pulled to the surface.

Without step 3, HA in a dry climate or in winter makes skin worse. This is the typical user error: buying a serum and using it overnight without a cream on top.

Hyaluronic acid layers safely with all actives: retinoids, vitamin C, niacinamide, azelaic acid, chemical exfoliants. It is not irritating and does not compete on pH.

Who actually benefits, who does not

Topical HA delivers real benefit for:

dry and dehydrated skin – through surface water retention;
skin recovering from fractional laser, professional cleansing, or chemical peels – faster recovery;
mature skin combined with an occlusive – temporary smoothing of fine surface lines.

It is unlikely to help if the goal is:

volumetric correction (that is the territory of fillers);
treating acne (azelaic acid, retinoids, benzoyl peroxide);
pigmentation lightening (azelaic, vitamin C, kojic acid, hydroquinone);
managing rosacea redness (brimonidine, rutin, azelaic 15%).

For oily skin without dehydration signs, an HA-heavy cream is overkill – a light serum or gel format does the job.

Who should be cautious

Contraindications to topical HA are minimal. Allergic reactions to the molecule itself are anecdotal – HA is identical to the endogenous form and not immunogenic. Reactions usually trace back to preservatives, fragrances, or other formula components.

Pregnancy and breastfeeding – no restrictions. HA is one of the few ingredient classes obstetricians and dermatologists do not flag, even in theory.

Active dermatitis, infection, or open wound – wait for remission before introducing a new product. Not because of HA itself, but because any new component in that situation adds an unnecessary variable.

Bottom line

Hyaluronic acid in skincare is a competent humectant, not an anti-ageing treatment.
Do not apply to dry skin – it backfires.
After serum or cream, layer an occlusive, especially in winter.
For volumetric correction or deep wrinkles, the answer is injectable HA performed by a physician, not a jar from a shelf.
Price barely correlates with effect: a 600₽ formula and a 6,000₽ formula perform comparably when the INCI matches.

Sources

Bukhari SNA, Roswandi NL, Waqas M, et al. Hyaluronic acid, a promising skin rejuvenating biomedicine: A review of recent updates and pre-clinical and clinical investigations using novel delivery systems. International Journal of Biological Macromolecules 2018;120(Pt B):1682–1695.
Pavicic T, Gauglitz GG, Lersch P, et al. Efficacy of cream-based novel formulations of hyaluronic acid of different molecular weights in anti-wrinkle treatment. Journal of Drugs in Dermatology 2011;10(9):990–1000.
Jiang D, Liang J, Noble PW. Hyaluronan as an immune regulator in human diseases. Physiological Reviews 2011;91(1):221–264.
Kerscher M, Bayrhammer J, Reuther T. Rejuvenating influence of a stabilized hyaluronic acid-based gel of nonanimal origin on facial skin appearance. Dermatologic Surgery 2008;34(5):720–726.
Wang F, Garza LA, Kang S, et al. In vivo stimulation of de novo collagen production caused by cross-linked hyaluronic acid dermal filler injections in photodamaged human skin. Archives of Dermatology 2007;143(2):155–163.
Papakonstantinou E, Roth M, Karakiulakis G. Hyaluronic acid: A key molecule in skin aging. Dermato-Endocrinology 2012;4(3):253–258.
FDA. Dermal Fillers Approved by the Center for Devices and Radiological Health (last update 2023).

Educational resource. The information on this page does not replace medical advice. Decisions about cosmetic or injectable products belong in conversation with a dermatologist or aesthetic physician who has examined your skin.

Hyaluronic Acid in Skincare: Which Form Works and What's Just Marketing