Hyaluronic acid is hardly a household word, yet this molecule is quickly becoming a go-to ingredient for anti-aging products. Widely found in the body, it's a major component of skin, cartilage and parts of the eye. In 2003, HA injections were approved by the U.S. Food and Drug Administration for smoothing wrinkles by adding volume under the skin, and it's also used in surgical procedures to promote wound healing. Now, companies are increasingly marketing HA topical formulations in anti-aging creams and serums, and a little knowledge will help you field shoppers' questions about this newly popular ingredient.
"There's a lot of misunderstanding of HA," says Ben Fuchs, a cosmetic chemist and owner of Sanitas Skincare in Boulder, Colo. "It has an amazing property of holding onto water, and is one of the two main ingredients in the ground substance of the dermis. However, it's a huge molecule, which doesn't penetrate very effectively through the surface of the skin." But according to Fuchs, HA can be a useful ingredient even if it doesn't penetrate the stratum corneum, the outer layer of the epidermis. "The stratum corneum itself can be plumped up with HA," he says, "and it has a wonderful effect for moisturizing and softening." Sanitas products contain high levels of HA to get the greatest possible effect, Fuchs says.
"[HA] is a large molecule," agrees Todd McMullen, director of sales and marketing for Hyalogic, a skin care company in Shawnee, Kan., specializing in HA topical products and oral supplements. "However, it's long like a rope instead of round like a basketball, so it is possible to absorb into the dermis." McMullen says HA products are especially effective for treating expression lines and fine wrinkles around the eyes.
In the past, the only natural source of hyaluronic acid was extracted from rooster combs, but advances in technology have made the substance more readily available. "Now it's fermented from bacteria by inserting a gene that produces HA in the bacteria itself," Fuchs says.
Although the bulk of research on HA has been done on injections, some studies also support topical applications. A 2008 study published in Current Oncology found HA gel reduces symptoms of dermatitis associated with radiation treatment, and its biocompatibility with human tissue makes it a promising candidate for wound healing and topical drug-delivery systems as well.
Mitchell Clute is a Fort Collins, Colo.-based freelance writer.