I’ve seen many products for dry skin that contains Sodium Hyaluronate, but in different concentrations and different molecular sizes. How should I select one that would work best on dry skin? Does the smallest molecule equate to the best?

Hyaluronic acid (HA) is a naturally occurring substance that promotes collagen synthesis in our skin. HA is well established as a cornerstone of skincare, due to its effect to help strengthen the collagen matrix of the skin, and improve the skin’s ability to retain moisture – which in turn improves skin elasticity, texture, and the appearance of fine lines.   

HA of different molecular weights penetrate the skin at different depths, and influence the inflammatory cascade at different points. The claim that low molecular weight HA penetrates the deepest and is therefore the most beneficial is essentially a marketing gimmick. For example, high molecular weight HA that does not penetrate the skin at all remains on the surface of skin, forming a protective barrier, and keeping the skin’s surface hydrated. Therefore, the ideal HA product contains a combination of HAs of different molecular weights, each selected for optimum benefit at the layer where it acts.

Dr. Felix Li
18 April 2019