Tetrahexyldecyl ascorbate is a form of vitamin C that's been modified to be more lipid soluble. This modification allows it to better penetrate the skin. The problem with most topical forms of vitamin C is they're water soluble and can't make it through the lipid-rich skin barrier to reach the dermis of skin where they could have maximal benefits. Tetrahexyldecyl ascorbate is able to successfully penetrate the epidermis and move to the layer underneath called the dermis. It's in the dermis that collagen, a protein that gives skin its youthful firmness and ability to resist wrinkles, is made.
Vitamin C has a variety of benefits for health and for maintaining healthy, youthful skin. It functions as an antioxidant, helping to offset oxidative damage that degrades collagen and leads to wrinkles and saggy skin. When skin is exposed to ultraviolet light from the sun, a sequence of events occurs that leads to free radical production. These free radicals damage skin cell membranes and activate enzymes that break down collagen and elastin, two most important proteins that keep skin firm and youthful. Vitamin C has the ability to donate electrons to free radicals so they aren't as damaging to cellular structures. Vitamin C isn't a substitute for sunscreen, but it does provide extra protection against oxidative damage that can lead to premature aging and skin cancer.
Another benefit of vitamin C is it stimulates collagen production. Since collagen provides skin with the support it needs to stay firm and youthful, this helps to reduce wrinkles and skin sagging. A study published in the Archives of Otolaryngology and Head and Neck Surgery found that participants who used topical vitamin C for three months experienced a decrease in fine lines and wrinkles and an improvement in skin texture. This was confirmed by a similar study published in the journal Dermatologic Surgery. Topical vitamin C also appears to be effective for lightening excessive skin pigmentation and improving the appearance of stretch marks. It also reduces redness and inflammation after laser surgery.
Despite the benefits of vitamin C, it has drawbacks. Some forms can't penetrate the epidermis and reach the dermis where it can stimulate collagen production. Plus, vitamin C is unstable and loses its effectiveness quickly, especially if exposed to air or light. Tetrahexyldecyl ascorbate is more stable than other vitamin C preparations, and is lipid-soluble, which allows it to reach the dermis of the skin where it can stimulate collagen production. Most vitamin C preparations remain on the surface of the skin where they guard against oxidative damage but have little effect on collagen production. Tetrahexyldecyl ascorbate is able to move into the dermis where it can offer additional anti-aging benefits by stimulating collagen production. It also stimulates the production of glycosaminoglycans, compounds present naturally in skin that bind and hold on to water. Levels of glycosaminoglycans decline with age and may account for some of the skin changes that occur as skin matures.
Is tetrahexydecyl sulfate safe? Like most forms of vitamin C, tetrahexyldecyl sulfate is safe. The Environmental Working Group classifies it as a low hazard cosmetic ingredient. Most forms of topical vitamin C cause skin irritation and redness, but tetrahexyldecyl sulfate is less irritating than other forms, although people with sensitive skin may experience mild burning and irritation.
Some manufacturers of cosmetic and skin care products add tetrahexyldecyl sulfate to their products due to its antioxidant and anti-aging benefits. Some types of products that contain this ingredient include facial moisturizers, eye creams, sunscreens, lip gloss, foundation and anti-aging products of all types. It's often combined with other antioxidants like vitamin E, retinols or peptides for additional anti-aging benefits.
All in all, tetrahexyldecyl sulfate is a form of vitamin C that's more stable and better able to penetrate skin to reach the dermis. By reaching the dermis, it can stimulate collagen production to help give skin greater firmness and resiliency. In addition, it helps to protect against damage due to sun exposure, lighten pigmented areas, treat stretch marks and improve skin texture. It does this safely and with minimal skin irritation.