By Mercedes Taylor
With a love for cosmetics from a young age, my curiosity knew that there was much more to the goop inside the jar than meets the eye. I graduated with a Bachelor’s of Science in Analytical Chemistry and moved to California to chase my dreams of becoming a cosmetic chemist, passionate about developing results-driven skincare. Now, I am the Product Innovation Manager for Youth To The People. My primary experience is in research and development, with a focus on both sustainability and the formulation of skincare, bringing natural ingredients to the forefront of the cosmetics market. I’m here to answer all of your skincare questions.
Question: How does hyaluronic acid work?
Answer: Hyaluronic acid’s main purpose is to act as a humectant, drawing water from our environment and delivering it to the lower layers of our epidermis. Its unique polymeric chemical structure allows it to capture water on the surface of our skin, and from there, it can work with our other natural moisturizing factors to deliver the water to the healthy cells below.
Our skin has a built-in lubrication system that allows it to stay relatively hydrated and moisturized in almost every environment. Our skin naturally contains lipids including tocopherols, squalene, phospholipids, and triglycerides that help create sebum. We also have a nourishing osmolyte system, composed of natural moisturizing factors like mineral ions, amino acids, and hyaluronic acid, that draws water from our environment into our skin. Both systems protect our skin cells from transepidermal water loss or dehydration.
Hyaluronic acid functions similarly, whether found within our skin barrier or as an ingredient in our skincare routines—it’s incredibly hydrating. Often listed as “sodium hyaluronate” in an ingredient list, its chemical structure allows for it to hold an abundance of water, due in part to the many disaccharide structures that make it up. When the polymer chain is very long, it gives it a high molecular weight, which causes it to stay on the surface level of our skin, capturing water molecules from our environment and hydrating the top layers of our stratum corneum.
Many other types of humectants work synergistically with hyaluronic acid to help skin stay hydrated, plump, and youthful. So in fact, low molecular weight hyaluronic acid also serves a purpose; when high molecular weight hyaluronic acid sits on the surface of the skin capturing water, it needs a reservoir to host that water so the water doesn’t evaporate from the surface, and that's where other humectants play a very important role, along with the osmolytes and humectants mentioned earlier.
One of the best osmolytes in nature is betaine. Betaine, also part of our natural moisturizing factors, acts as a water reservoir for hyaluronic acid to deliver necessary water to the lower layers of our skin which is where new skin cells are being formed, a process that requires lots of hydration. Betaine and other amino acids do an amazing job of retaining water molecules for extended periods of time so that your skin continues to feel hydrated even when your environment is dehydrating—think deserts, airplanes, or constant air conditioning.
Water, perhaps the most important ingredient in our routines, keeps our skin happy for many reasons, and we need an ample source within our skin’s barrier for the ingredients in our skincare routines to function efficiently. For best results, hyaluronic acid should be incorporated into any skincare regimen that also includes other humectants and moisturizers to protect against transepidermal water loss.