Sometimes people ask me what makes FutureDerm different than other beauty or skin care blogs. Well, the fact that not one, but several, readers have asked me, “What makes Tetrahexyldecyl ascorbate different from other forms of vitamin C?” certainly is a differentiation factor, in and of itself.
Tetrahexyldecyl ascorbate is a form of vitamin C that is oil-soluble. What makes THA special is that it has been shown in peer-reviewed studies to penetrate both the epidermis (the uppermost layer of skin) and dermis (the deepest layer of skin) (Clinics in Dermatology, 2008).
The issues with any vitamin C derivative (i.e., any form of vitamin C other than L-ascorbic acid), however, are numerous. First, companies who create products with vitamin C alternatives tend not to disclose the percentage of vitamin C derivative included. So whereas you can easily compare a 15% Skinceuticals L-ascorbic acid product with a 20% Dr. Dennis Gross L-ascorbic acid product, you can’t necessarily compare one tetrahexyldecyl ascorbate product to another as easily, much less compare a tetrahexyldecyl ascorbate product to a ascorbyl glucosamine product. That’s one issue.
Another issue with vitamin C derivatives are that they typically need to be converted to vitamin C within the skin. For instance, ascorbyl glucosamine needs to be broken down into L-ascorbic acid and glucosamine by enzymes found naturally within the skin in order to have any activity at all. On the other hand, L-ascorbic acid on its own has been shown to have effects, without needing to have any sort of breakdown or “activation” within the skin.
So while I like a good vitamin C derivative, I am also careful to always keep L-ascorbic acid itself in my regimen, in a concentration of at least 15%. That said, I do like using both L-ascorbic acid and tetrahexyldecyl ascorbate in my routine.
As for the best products with tetrahexyldecyl ascorbate, I recommend Peter Thomas Roth Potent-C Power Serum (with a whopping 20% THD ascorbate) and our own FutureDerm Vitamin CE Caffeic (with 8% THD and 8% LAA).