Hyaluronic acid, explained

The hydration hero. What hyaluronic acid can and can’t do for skin over 40, and why the type matters.

Good evidence for hydration

What it does

Hyaluronic acid (often listed as sodium hyaluronate) is a natural moisture-binding molecule in our skin. In skincare, it draws water into the top layers, so skin looks plumper and fine lines look softer.

Why it suits skin over 40

Skin makes less of its own hyaluronic acid with age, and it gets drier around menopause. A hyaluronic serum is an easy, gentle way to put moisture back, and it works with almost every other active.

Does the type matter?

Large (high molecular weight)

Sits on the surface and forms a moisture-holding film. Instant smoothness.

Small (low molecular weight or “hydrolysed”)

Reaches a little deeper into the top layers. Many Korean serums combine several sizes.

How to use it

Apply to damp skin, morning and night.
Always follow with a moisturiser to seal it in, especially in dry or heated rooms.
It’s fine with retinoids, vitamin C, niacinamide and acids.

What the research shows

In a 60-day study, 76 women aged 30 to 60 applied a 0.1% hyaluronic acid cream around one eye and a plain cream around the other. All the hyaluronic acid creams improved hydration and elasticity, and the smaller types also reduced wrinkle depth compared with the plain cream.

Pavicic and colleagues, Journal of Drugs in Dermatology, 2011 [1]

Our take: hyaluronic acid is a gentle, reliable hydrator that makes dry skin over 40 look plumper and smoother. It won’t rebuild collagen like a retinoid, but it pairs with everything and is worth having in your routine.

Compare prices: Hyaluronic acid

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Good to know

Does hyaluronic acid work on its own?

It works best on damp skin with a moisturiser on top. On its own in very dry air, it can feel tight.

Is hyaluronic acid safe in pregnancy?

Yes, it’s considered one of the safest skincare ingredients.

Is it the same as hyaluronic acid fillers?

No. Fillers are injected and physically add volume. Skincare hyaluronic acid hydrates the surface.

Sources

Pavicic T et al. Efficacy of cream-based novel formulations of hyaluronic acid of different molecular weights in anti-wrinkle treatment. J Drugs Dermatol. 2011;10(9):990-1000.

This page is general information, not medical advice. Last updated 30 October 2026.