Ma
Magnesium Ascorbyl Phosphate
Magnesium Ascorbyl PhosphateAntioxidant
Stable water-soluble vitamin C derivative. Effective for brightening at lower percentages than L-ascorbic acid.
What it does
Magnesium ascorbyl phosphate is a stable, water-soluble vitamin C derivative that converts to ascorbic acid on the skin. It's stable at neutral pH (5–7), which makes it easier to combine with niacinamide than L-ascorbic acid is. MAP delivers measurable brightening and antioxidant effects at 3–5%, comparable to higher percentages of less stable vitamin C forms.
The evidence, graded
strongVitamin C shows brightness and tone-evening improvements in 4–8 weeks. Collagen-mediated firmness benefits take 12+ weeks. Photoprotection benefits are immediate when paired with sunscreen.Humbert 2003 · Experimental Dermatology ↗
emergingVitamin C, vitamin E, and ferulic acid show synergistic photoprotection. The combination is more stable and doubles photoprotection compared to vitamin C alone.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
map, vitamin c, ascorbic acid
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