Cited skincare — peer-reviewed evidence, no upsell.
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, 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
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

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

Pairs worth knowing

This page is public and indexed on purpose (unlike profiles and drops, which are unlisted) — it’s the citation behind shared ingredient cards, and it should be findable.
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