HYALURONIC ACID: the star ingredient, explained by the doctors!

Hyaluronic acid (H.A).
You have definitely read this name on a label, heard it in an advertisement, or seen it on your bathroom’s favorite bottle.
Star molecule of cosmetics, it intrigues as much as it seduces. But behind this popularity, what do we really know about this substance with a thousand virtues?

Today, we dive with our Doctors into the heart of this fascinating molecule to understand, without marketing filters, how it works, why it is essential… and above all, how to use it intelligently for your skin.

WHAT IS HYALURONIC ACID?

A 100% natural molecule discovered long before cosmetics.

The story begins in 1934, in an American laboratory. Two researchers, Karl Meyer and John Palmer, isolate a mysterious substance in the vitreous humor of the bovine eye. They name it hyaluronic acid – from Greek hyalos, which means “glassy.”
They unknowingly had just gotten their hands on an essential molecule for life.

Far from being a marketing invention, hyaluronic acid is 100% natural. It is found everywhere in the human body: in the eyes, brain, lungs, joints, umbilical cord, breast milk… and especially in the skin (Necas and al., 2008).

Hyaluronic acid and the skin: a lasting story.

Before being a skincare ingredient, hyaluronic acid already lives in your skin.
It is even found in the greatest quantity here: about half of the total stock in the human body ! (Stern et al., 2008).

A natural pillar of the dermis.

Imagine the dermis (the deep layer of the skin) as a mattress.
Collagen and elastin fibers are the springs, and hyaluronic acid is the hydrating foam which keeps everything supple, plump, and comfortable.
It attracts water and retains water to preserve the firmness and elasticity of the skin.

Present at all levels of the skin.

In the superficial layers, it hydrates and protects.
Deeper down, it supports the structure and helps cells produce collagen and elastin.
You could say that hyaluronic acid is to the skin what water is to a plant: without it, everything wilts faster.

The secret of baby skin.

This is actually one of the secrets of that famous “baby skin”: infant skin naturally abounds with hyaluronic acid. A true biological water reserve, it forms a gel that maintains hydration and gives their skin that plump and velvety appearance we all envy. Babies are, without a doubt, the champions of hydration across all categories!

A NATURAL MOLECULE AT THE HEART OF MEDICINE

Before invading our bathrooms, hyaluronic acid had a brilliant medical career.
In ophthalmology, it hydrates and protects the surface of the eye (Shimmura and al., 1995).
In orthopedics, it is injected into joints to restore lubrication and relieve osteoarthritis pain (Barbucci and al., 2002).
In gynecology, it protects embryos during in vitro fertilizations (Ekin and al., 2011).
And of course, it has become essential in dermatology and aesthetic medicine.

THE BENEFITS OF HYALURONIC ACID

The guardian of hydration.

Hyaluronic acid acts as a true biological sponge.
Its mission? Capture and retain water in the skin tissues to preserve hydration and skin suppleness.
Result: bouncy, smoothed, radiant skin – in short, “healthy” skin.

But this effect is not magic, it is cellular.
In the skin, two main actors participate in its natural production:

The keratinocytes, located in the epidermis, which produce surface HA. Their role is to maintain the hydrolipidic film and limit water loss. (Tammi and et al., 1988)

The fibroblasts, located in the dermis, which produce HA deep down. They ensure cohesion and structure of the skin tissue, in collaboration with the collagen and theelastin (Nugens and et al., 2010).

These two cell populations work hand in hand to create a a two-level water reservoir : the epidermis retains moisture on the surface, while the dermis holds water and redistributes it.

Imagine: 1 gram of hyaluronic acid can hold up to 1000 times its weight in water. Yes, a single molecule can trap the equivalent of an entire bottle of mineral water!

It is this exceptional capacity that gives the skin its bouncy and elastic texture.

But to enjoy all its benefits, one must understand one essential thing: not all forms of hyaluronic acid are equal.
It is their size – or molecular weight – which determines their role.

2. The anti-aging power.

With age, our skin produces less hyaluronic acid.
From 30 years old, its quantity and quality decrease: the skin becomes thinner, loses volume, features sag and wrinkles set in.
At 50 years old, about only half (Meyer et al., 1994).

HA acts on several levels:

It naturally fills the intercellular spaces to smooth wrinkles.

It stimulates collagen synthesis, improving firmness.

It protects the extracellular matrix, strengthening the skin structure.

The effect? Denser skin, a redefined contour, a rested face.
Without freezing expressions – and that is anything but trivial.

3Elasticity: the return of the bounce!

By stimulating collagen and elastin production, hyaluronic acid helps the skin regain its natural suppleness.
Tissues tighten, the face regains tone.
Applied regularly, it acts like training for the skin: day after day, it learns to regenerate faster.

4. The science of size: small, medium, or large?

There are several sizes of hyaluronic acids, classified by their molecular weight:

Type	Approximate size	Action	Nature of the action
Very high molecular weight	> 1,000 kDa	Forms an invisible film on the skin surface	Mechanical action: limits dehydration (Essendoubi and al.,2016)

High molecular weight	500–1 000 kDa	Strengthens the skin barrier and soothes	Gentle mechanical + biological action (Essendoubi and al.,2016)
Medium molecular weight	100–500 kDa	Stimulates fibroblasts	Biological action: reactivates collagen (Pavicic and al., 2011).
Low molecular weight	20–100 kDa	Penetrates more deeply	Intense biological action (Turlier and al., 2013).

Each category acts at a different level, but it is their combination which guarantees optimal effectiveness.
It is the very principle of molecular synergy that we apply in our formulas: a harmony between sizes for hydrated, plumped, and visibly firmer skin.

DO WE REALLY NEED TO SUPPLEMENT THE SKIN WITH IT?

The short answer: yes, but intelligently. Our body produces and destroys hyaluronic acid every 24 hours, a lightning cycle! (Fraser et et al., 1997). Bringing HA topically (cream, serum, mist) helps compensate for this natural deficit, supports the skin barrier, and reactivates fibroblasts. It is therefore much more than a simple glow boost: it is a biological restart of the youth capital (Pavicic and et al., 2011).

THE DIFFERENT FORMS OF HYALURONIC ACID: ONE ACTIVE INGREDIENT, SEVERAL FACES.

Hyaluronic acid does not have just one life. Depending on its form, it acts at different times in your routine and at varying depths of the skin. Here is how to distinguish them, without losing you in jargon.

1- The serum: the essence of performance.

Concentrated, precise, it is the most effective form to target dehydration and lack of bounce.
Thanks to its fluid texture, it penetrates quickly and delivers a high dose of HA, often in several molecular weights.
At Novexpert, the Hyaluronic Acid Booster Serum contains 4 sizes of HA and 3.2% pure powder — a rare balance between power and tolerance.
💡 To be applied on slightly damp skin, before the cream, to maximize penetration.

2- The cream: the comfort guardian.

The cream acts as a hydrating cover : it locks water into the skin and prolongs the serum’s effects.
Creams rich in hyaluronic acid mainly rely on high and very high molecular weights to smooth, protect, and soothe.
It is the “cocoon” form of HA, ideal for dry or sensitive skin.

3- The mist: the underestimated ally.

Often forgotten, the mist is a secret weapon for instant hydration.
It contains light forms of HA that settle like a plumping water veil, perfect for:

Rehydrate the skin during the day (especially in air-conditioned offices),

Reactivate radiance before a treatment or makeup,

Give a “boost” of hyaluronic acid between two products.

💡 Novexpert tip: spray a mist before serum to enhance active ingredient absorption.

4- The mask: the express rejuvenation effect.

In the form of a sheet or thick cream, the hyaluronic acid mask acts as hydration bath.
In 10 to 15 minutes, it replenishes the skin with water and restores suppleness.
Ideal after a flight, sun exposure, or extreme cold.

5- Capsules: the “in & out” route.

Taking hyaluronic acid orally may seem surprising, but studies have shown that it improves skin hydration and reduces wrinkle depth after 8 to 12 weeks (Michelotti et al…2021).
It acts from within, complementing topical care, to support the natural production of HA by fibroblasts.
As always at Novexpert: priority on purity, bioavailability, and safety.

Specific areas: face, lips, eye contour

Each area of the face has its needs:

Eye contour : favor low molecular weight HA molecular weight to smooth crow’s feet and fill hollow dark circles, ideally a multi-weight formula, combining high weight for the film-forming and protective effect and low weight for suppleness and the “bounce” effect of the contour.

Lips : reshape contours, plump and soften “barcode” wrinkles.

Forehead and nasolabial folds : restore suppleness and fill hollows.

SHOULD YOU GO FOR HYALURONIC ACID INJECTIONS?

And if you opt for the injections, know that one syringe (about €240 to €450) is often enough to treat an area.
The results are immediate and last 8 to 18 months (Asher et et al., 2004).

But one detail is important: the hyaluronic acids used in injections are cross-linked, that is to say modified to resist natural degradation.
Their lifespan is extended… but their exact fate in the skin remains unknown.

AND MEN?

A skin is a skin.
Yes, men's is about 25% thicker, but this does not change the mechanism of action of hyaluronic acid.
It hydrates, plumps, and repairs equally well all skin types with or without beard.
Bonus: it soothes post-shave irritations and promotes healing micro-cuts (Harris et al., 1999).

💡 But some habits can make a difference:

Apply just after shaving
This is when the skin is most receptive. Hyaluronic acid acts like a “hydrating bandage,” limiting redness and tightness sensations.

Hydrate even beard areas
Under the beard too, the skin breathes. A fluid serum penetrates easily and prevents dehydration, often invisible but very real.

Prevention rather than correction
Fine lines often appear later in men, but good hydration from 25-30 years delays their onset.

BEYOND THE FACE: JOINTS AND HAIR

Hyaluronic acid also acts where it is least expected.

Joints : in medicine, it is injected into knees, hips, or shoulders to compensate for synovial fluid loss. Result: better lubrication and reduced osteoarthritis pain.

Hair : it hydrates the scalp, nourishes follicles, and restores shine and volume to dehydrated hair.

HYALURONIC ACID, COLLAGEN, BOTOX: MUST YOU CHOOSE?

Hyaluronic Acid vs Collagen: an alliance more than a fight

Imagine your skin as a mattress:

The collagen, these are the springs : it provides structure and firmness.

Thehyaluronic acid, it is thefoam : it fills, hydrates, and gives bounce.

One without the other? Incomplete.
It is thesynergy between these two molecules that create young skin: HA instantly plumps, while collagen sustainably strengthens the framework.

Supplements combining both are ideal after 30 years: they work together on hydration, density and skin sagging.

Hyaluronic Acid vs Botox: two different professions

The Botox (botulinum toxin) blocks the muscle contractions responsible for expression wrinkles: it freezes movement.
Thehyaluronic acid, it hydrates and rebuilds.
It fills static wrinkles, restores volume, and improves skin texture without affecting facial mobility.

In summary:

Botox prevents the wrinkle from forming.

Hyaluronic acid the naturally fills.

THE ESSENTIAL TO REMEMBER

✔ Hyaluronic acid is naturally present in our body and represents half of the skin's hydration capacity.
✔ It acts as a molecular sponge, capable of retaining up to 1000 times its weight in water.
✔ Its different molecular weights ensure a complete action: hydration, regeneration, and firmness.
✔ With l’âage, its production decreases: therefore it is necessary support the skin thanks to well-formulated care.
✔ The formulas véganes from bacterial fermentation guarantee a hyaluronic acid natural and biodegradable.
✔ Injections offer rérapid results, but l’Topical HA acts every day in respect of life.

References :

Bukhari S. N. A. et al. (2018). Hyaluronic acid, a promising skin rejuvenating biomedicine: a review of recent updates and pre-clinical and clinical studies. Dermatologic Therapy, 31(5), e12679.

Ekin M. et al. (2011). The role of hyaluronic acid in reproductive medicine and gynecology. Clinical and Experimental Obstetrics & Gynecology, 38(1), 1–6.

Essendoubi, M., Gobinet, C., Reynaud, R., Angiboust, J. F., Manfait, M., & Piot, O. (2016). Human skin penetration of hyaluronic acid of different molecular weights as probed by Raman spectroscopy. Skin Research and Technology.

Fraser, J. R. E., Laurent, T. C., & Laurent, U. B. G. (1997). Hyaluronan: its nature, distribution, functions and turnover. Journal of Internal Medicine, 242(1), 27–33.

Harris E. N. et al. (1999). Hyaluronan in wound repair and inflammation. Matrix Biology.

Meyer, L. J., & Stern, R. (1994). Age-dependent changes of hyaluronan in human skin. Journal of Investigative Dermatology, 102(3), 385–389.

Michelotti, A., Cestone, E., De Ponti, I., Pisati, M., Sparta, E., & Tursi, F. (2021). Oral intake of a new full-spectrum hyaluronan improves skin profilometry and ageing: a randomized, double-blind, placebo-controlled clinical trial.

Necas J. et al. (2008). Hyaluronic acid (hyaluronan): a review. Veterinary Medicina, 53(8), 397–411.

Nusgens, B.-V. (2010). Hyaluronic acid and extracellular matrix: a primitive molecule? Annales de Dermatologie et de Vénéréologie, 137(Suppl. 1), S3–S8.

Pavicic, T., Gauglitz, G. G., Lersch, P., Schwach-Abdellaoui, K., Malle, B., Korting, H. C., & Farwick, M. (2011). Efficacy of cream-based novel formulations of hyaluronic acid of different molecular weights in anti-wrinkle treatment. Journal of Drugs in Dermatology, 10(9), 990–1000.

Shimmura S. et al. (1995). Hyaluronic acid as a tear substitute. British Journal of Ophthalmology, 79(11), 1007–1011.

Stern, R., & Maibach, H. I. (2008). Hyaluronan in skin: aspects of aging and its pharmacologic modulation. Clinics in Dermatology, 26(2), 106–122.

Tammi, R., Ripellino, J. A., Margolis, R. U., & Tammi, M. (1988). Localization of epidermal hyaluronic acid using the hyaluronate binding region of cartilage proteoglycan as a specific probe. Journal of Investigative Dermatology, 90(4), 412–414.

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