A very stable and promising form of the skincare superstar, Vitamin C. If you do not know why Vitamin C is such a big deal in skin care, you can catch up here. In short, Vitamin C has three proven magic abilities: antioxidant, collagen booster, and skin brightener. The problem, though, is that it's very unstable, turns brown and becomes ineffective in no time (after a few month) and the cosmetics industry is trying to come up with smart derivatives that are stable and have the magic properties of pure Vitamin C.
Ethyl Ascorbic Acid or EAC for short is an "etherified derivative of ascorbic acid" that consists of vitamin C and an ethyl group bound to the third carbon position. This makes Vitamin C very stable and soluble in both water and oil.
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3-O Ethyl Ascorbic Acid
Rating: BEST
Benefits: Anti-Aging, Evens Skin Tone, Dark Spot Fading
Categories: Antioxidant
3-O Ethyl Ascorbic Acid at a Glance
A more stable derivative of pure vitamin C (ascorbic acid)
Has water- and oil-soluble properties
Capable of fading hyperpigmentation
Offers anti-aging benefits on par with vitamin C
3-O Ethyl Ascorbic Acid Description
3-O ethyl ascorbic acid is a stable, water- and oil-soluble derivative of pure vitamin C (ascorbic acid) that offers all of the primary benefits vitamin C is known for, such as brightening, wrinkle reduction, visible firming, fading hyperpigmentation to restore a more even skin tone and offsetting numerous triggers of environmental damage.
As a modified and more stable version of pure vitamin C, 3-O ethyl ascorbic acid must be converted to vitamin C within skin by sodium-dependent proteins. This process within skin’s surface layers helps ensure skin benefits.
Due to the conversion to pure vitamin C being a slower process, 3-O ethyl ascorbic acid is considered a more tolerable form of vitamin C. However, like pure vitamin C, the ethyl form requires an acidic pH range (4–5.5) for optimum stability. This pH range is higher than what ascorbic acid needs for ideal stability, making 3-O ethyl ascorbic acid an intriguing alternative if your skin hasn’t been able to tolerate higher-strength (10% and up) vitamin C (ascorbic acid) products.
Research has shown which non-irritating ingredients aid the penetration of this ingredient into skin’s surface, and they include pentylene glycol, glycerin, 1,2 hexanediol, diisostearyl malate and various propylene glycol derivatives, although this list is not exhaustive.
Usage levels of 3-O ethyl ascorbic acid in skin care typically fall between 0.5–5%. Due to its stability, lesser amounts are needed compared with pure vitamin C. Levels above 5% may also be used, depending on desired benefits. Amounts up to 30% have been shown to be non-irritating on human skin samples.