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Magnesium Hydroxide

What Magnesium Hydroxide is & what it does

Magnesium Hydroxide is an inorganic mineral compound, the magnesium salt of hydroxide. In cosmetic and sunscreen formulas it is used mainly as a buffering agent to adjust and stabilize pH, and it can also serve as an absorbent or opacifying ingredient. Its alkaline nature is the property that makes it useful for neutralizing acidity in a formula.

Is Magnesium Hydroxide safe in skincare?

Magnesium Hydroxide is a mineral compound widely used in cosmetics as a pH buffer and absorbent and is generally considered safe for topical use in finished formulas. It is the same compound familiar from antacids, used here in small, formulation-level amounts. Its alkaline nature means it is balanced within the product to keep the finished pH skin-friendly.

What does Magnesium Hydroxide do in skincare?

In skincare and sunscreen formulas, Magnesium Hydroxide is used mainly as a buffering agent that helps adjust and stabilize pH. It can also act as an absorbent or opacifying ingredient. Its alkaline character is what makes it useful for neutralizing acidity in a formula.

Is Magnesium Hydroxide natural or synthetic?

Magnesium Hydroxide is an inorganic mineral compound that can be sourced from minerals or produced synthetically, with the final ingredient being chemically the same either way. It is a simple, well-defined mineral salt rather than a botanical. As a mineral-based ingredient, it contains no animal-derived material.

Sunscreens with Magnesium Hydroxide

We rate 5 sunscreens that contain it:

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