Hyaluronic acid: what it is, how it affects your skin and the best products

As Dr Sam Bunting, Harley Street dermatologist and founder of Dr Sam Skincare Club, explains: “It’s a water-holding gel with the ability to hold 1000 times its own weight in moisture. When it’s applied topically, skin acts as a highly-effective barrier and those hyaluronic acid molecules are too big to squeeze through the dermis (the layer of skin beneath the epidermis), which is where it needs to be to help plump lines and wrinkles.”

So instead, it sits on the skin’s surface and acts as a moisturiser through its humectant (water-attracting) properties.

“That means it draws water into skin to keep it hydrated, supple and makes sure it keeps it functioning effectively as a barrier,” says Dr Bunting.

If you’re applying hyaluronic acid to a very dry face, it can actually end up drawing moisture from the deeper levels of your skin, which in turn will cause more harm than good and leave your complexion feeling tight and uncomfortable.

It’s a problem that usually occurs when humidity levels are extremely low – meaning there’s a lack of moisture in the air. 

To counteract that issue, Sonia Deasy, founder of skincare brand Pestle & Mortar, always recommends layering hyaluronic acid serum with a moisturiser.

“It helps seal it into your skin and provides a barrier against moisture loss,” she explains.

Deasy also advises applying serum to damp – not completely dry – skin for better results.