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Magnesium Ascorbyl Phosphate

What Magnesium Ascorbyl Phosphate is & what it does

A stable, gentle vitamin C derivative that brightens, hydrates, and provides antioxidant protection. It suits sensitive skin and resists degradation.

What is Magnesium Ascorbyl Phosphate and what does it do in sunscreen?

Magnesium Ascorbyl Phosphate is a stable form of vitamin C. In a sunscreen it works as an antioxidant that helps defend skin against free radicals, and it is associated with a brighter, more even-looking tone. It also adds a little hydration, and it is gentle enough for sensitive skin.

Is Magnesium Ascorbyl Phosphate safe?

Yes. Magnesium Ascorbyl Phosphate is one of the milder vitamin C derivatives and is well tolerated, including by people who find pure vitamin C (ascorbic acid) too strong. It is non-irritating at the levels used in skincare. A patch test is still sensible if your skin is very reactive.

Does Magnesium Ascorbyl Phosphate clog pores?

Generally no. It is a water-soluble vitamin C salt used in small amounts, not a heavy oil or wax, so it is an unlikely pore-clogging culprit. If you are breaking out, the richer emollients and oils elsewhere in a formula are far more likely the cause.

Is Magnesium Ascorbyl Phosphate a good form of vitamin C?

Yes, for stability and gentleness it is a strong choice. Unlike pure ascorbic acid, which oxidizes quickly and can sting, Magnesium Ascorbyl Phosphate resists degradation and stays milder on skin. That makes it well suited to a daily sunscreen, where you want the antioxidant benefit without the irritation.

What else is Magnesium Ascorbyl Phosphate called?

On a label it goes by its INCI name, Magnesium Ascorbyl Phosphate, sometimes shortened to MAP. It is the magnesium salt of an ascorbic acid (vitamin C) phosphate. It usually appears low on the ingredient list among the antioxidants and brightening actives.

Sunscreens with Magnesium Ascorbyl Phosphate

We rate 112 sunscreens that contain it, showing the top 10 by overall score:

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