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Sodium Ascorbyl Phosphate
Sodium Ascorbyl PhosphateAntioxidant
The most stable everyday form of vitamin C. It turns active on skin and also works on acne bacteria. Effects are gradual.
What it does
It’s a stable form of vitamin C that your skin turns into the active form. It’s the most stable of the common forms and doesn’t need the very acidic formula pure vitamin C does. It also works against acne bacteria, which is why it shows up in brightening serums for acne. Effects are gradual.
The EU’s ingredient database lists it as an antioxidant (slows reactions with oxygen, like going rancid).European Commission, CosIng (© European Union, CC BY 4.0) · uses put in plain words by Drop ↗
The evidence, graded
strongTwo vitamin C trials measured at 12 weeks, and at 3 and 6 months. In a half-face study of ten people, a 10% ascorbic acid and 7% tetrahexyldecyl ascorbate gel reduced wrinkling over 12 weeks, with biopsy evidence of new collagen. In a 6-month study, a 5% cream on the low neck and arms raised the global score and microrelief density. Both graded pigment and neither beat its own vehicle on it. A review of seven trials did report lightening.Humbert 2003 · Experimental Dermatology ↗ emergingFine together — vitamin C and vitamin E are both antioxidants, and they were studied as a pair: vitamin C (15% L-ascorbic acid) with 1% vitamin E. Adding ferulic acid, another antioxidant, made the vitamins last longer and doubled the protection against lab UV light, measured by redness and damaged skin cells.Lin 2005 · Journal of Investigative Dermatology ↗ Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.
Also known as
SAP, vitamin c, ascorbic acid
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