Hyaluronic acid (HA) is a substance produced naturally within the skin, throughout the dermis and epidermis (the upper part which continually regenerates). HA is a type of humectant, which means it can draw water towards it, via its slightly charged -OH bonds.
Hyaluronic acid is an example of a particularly powerful humectant, as studies have shown that it can attract up to 1000 times its own molecular weight in water molecules, leading to more hydrated and therefore plumper-looking skin.
You may have noticed more recently that products are being launched with different ‘weights’ of hyaluronic acid, which basically means how big the molecule is. High, medium and low molecular weights differ in how far they can penetrate the skin, and therefore the layer of the skin that they are designed to affect.
Higher weight molecules sit on the surface of the skin and work by pulling water from the atmosphere to plump the very outer layer of the skin (this is more effective in humid environments).
The medium and low weight molecules can penetrate further through the epidermis, pulling water from the dermis upwards to plump up the epidermis, giving you more youthful-looking and hydrated skin. You will often notice an immediate effect with products containing this ingredient, which is why it has really hit the big time recently (despite being around for a long time).
Hyaluronic acid can also be injected as a filler into the skin. Restylane is a branded example of this. The active works in just the same way, but the injectable form allows higher concentrations to be delivered into the skin and guarantees the placement directly into the dermis.
Topical products containing hyaluronic acid work for all skin types – particularly normal to dry skins, or those with dehydrated combination skin. It is a water-soluble active and will be most effective in serum format (particularly those with multi-weight variants), so opt to add this ingredient into your regime in your serum rather than your cream.
We hope this helps to explain Hyaluronic acid in more detail. Do you use it? Do you love it? If you have any questions please do let us know – we’d love to hear from you.