Hyaluronic acid is a polysaccharide (large sugar molecule) that naturally exists in the skin, connective tissues, and neural tissues.
It is a component of the epidermis and extracellular matrix in the dermis of the skin where it acts to hydrate the tissue, restore osmotic balance, and stabilise the skin structure. With age, the amount of hyaluronic acid and renewal of hyaluronic acid within the skin declines, and this contributes to the signs of aging and dryness seen on the skin overtime.
In skincare formulations, hyaluronic acid is a powerful moisturising and anti-inflammatory ingredient. This is because hyaluronic acid can bind water molecules, up to 1000x its weight. It also decreases the depth and appearance of wrinkles as it has a plumping and smoothing action.
The penetration of hyaluronic acid into the skin iS affected by the size of hyaluronic acid. It is possible to have many forms of hyaluronic acid with various molecular weights. High molecular weight hyaluronic acid stays on the outer layers of the skin and has hydrating benefits. Medium molecular weight hyaluronic acids can penetrate the dermis where it can have cell repair and wound healing benefits. Low molecular weight hyaluronic acid can penetrate deeper into the skin, CAN reinforce the junctions in-between cells, and also provide anti-aging benefits.
In nutraceutical skin supplements, hyaluronic acid also provides anti-aging benefits. In a 12-week clinical trial, daily supplementation of hyaluronic acid (2kda and 300kda) improves skin suppleness, lustre, and reduces the appearance of wrinkles.²
References
1. Juncan A, Moisă D, Santini A, Morgovan C, Rus L, Vonica-Țincu A et al. Advantages of Hyaluronic Acid and Its Combination with Other Bioactive Ingredients in Cosmeceuticals. Molecules. 2021;26(15):4429.
2. Oe M, Sakai S, Yoshida H, Okado N, Kaneda H, Masuda Y et al. Oral Hyaluronan Relieves Wrinkles: A Double-Blinded, Placebo-Controlled Study Over a 12-Week Period. Clinical, Cosmetic and Investigational Dermatology. 2017;Volume 10:267-273.