Magnesium Hydroxide
What is Magnesium Hydroxide?
Magnesium hydroxide, chemically Mg(OH)2, is an inorganic compound formed by reacting magnesium oxide with water, resulting in a fine, white, insoluble powder. Naturally found in minerals like brucite, it serves as a versatile ingredient in cosmetics such as powders, cleansers, emulsions, and deodorants. In formulations, it functions primarily through its absorbent properties, drawing in water and sebum to mattify skin and lighten texture. As an alkaline substance, it raises pH levels to optimize product stability and efficacy while maintaining a mild profile. Its buffering action helps resist pH fluctuations from other ingredients or skin contact, ensuring consistent performance. Commonly used in concentrations that align with safety assessments from regulatory bodies, it contributes to lightweight, non-greasy finishes in various skincare formats.
Roles in Formulation
This ingredient serves the following purposes in cosmetic formulations:
Benefits
Absorbs excess sebum and moisture for a drier, less shiny feel.
Supports gentle cleansing by aiding impurity removal without harshness.
Softens product texture and skin touch through balanced formulation pH.
Who It's For
A quick guide for who this ingredient may suit (and who should be cautious).
| Who May Benefit | Who Should Avoid |
|---|---|
| People with oily or combination skin seeking mattifying effects. | Those with known magnesium sensitivities, despite rarity. |
| Individuals preferring pH-balanced, stable cleansers. | People using highly acidic formulations where pH shift is undesired. |
| Users wanting non-comedogenic absorbent ingredients in daily routines. | Individuals preferring anhydrous products without any water-absorbing agents. |
Safety Notes
- Rated low to moderate hazard by EWG, with safe use confirmed in cosmetic reviews.
- Non-comedogenic and typically non-sensitizing per authoritative assessments.
Frequently Asked Questions about Magnesium Hydroxide
What does magnesium hydroxide do in skincare?
It absorbs oils and water, adjusts pH upward, and buffers formulations for stability.
Is it safe for sensitive skin?
Generally yes, with low irritation potential from safety reviews, but patch test recommended.
Can it help with oily skin?
Yes, its absorbent role reduces shine and greasiness effectively.