Ethyl Ascorbyl Ether
Ethyl Ascorbic Acid (EAC), also known as 3-O-Ethyl Ascorbate, is an etherified derivative of ascorbic acid (Vitamin C) in which an ethyl group is bound to the third carbon position. This modification makes it highly stable and soluble in both water and oil, overcoming the well-known instability of pure Vitamin C. It is claimed by manufacturers to be metabolized in the skin into pure ascorbic acid, with a notably high ascorbic acid content of 86.4% compared to the typical 50–60% found in other derivatives.
EAC is reported to provide antioxidant and anti-inflammatory effects, support collagen production, and deliver skin-brightening benefits. Clinical in-vivo data (tested on real people) supports that 2% EAC can improve skin tone and brighten the skin. Absorption into the skin has been demonstrated in an animal study, where it appeared to penetrate better than Ascorbyl Glucoside.
Many of the claimed benefits (collagen boosting, antioxidant activity, skin conversion to ascorbic acid) currently rest primarily on manufacturer claims rather than independent clinical data; the source characterizes EAC as "very promising but not fully proven."
