Aluminum/Magnesium Hydroxide Stearate

What is Aluminum/Magnesium Hydroxide Stearate?

Aluminum/Magnesium Hydroxide Stearate is a powdered complex derived from stearic acid, a saturated fatty acid sourced from vegetable oils or animal fats, combined with aluminum and magnesium hydroxides through a chemical reaction process. Primarily used in color cosmetics such as foundations, powders, and lip products, as well as skincare emulsions like creams and lotions, it acts by selectively absorbing liquids to control viscosity, yielding a desirable semi-solid consistency that aids spreading and application. As an emulsion stabilizer, it reinforces the interface between water and oil phases, inhibiting coalescence and maintaining homogeneity over time. This multifunctional property supports formulation integrity without altering sensory attributes significantly.

Comedogenic Rating 0/5 Low risk of clogging pores
EWG Safety Rating 1 View on EWG →

Roles in Formulation

This ingredient serves the following purposes in cosmetic formulations:

Viscosity controlling agent
Adjusts thickness to the desired level for stability and usability, improving dispensing, suspension, and texture across many formulation types.
Emulsion stabilizer
Improves emulsion robustness by preventing droplet coalescence and phase separation, often by thickening, structuring, or strengthening the interfacial layer.

Benefits

Enhances product thickness for smooth dispensing and even application.

Strengthens emulsion integrity to avoid phase separation during storage or use.

Suspends particles like pigments for uniform coverage and stability.

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 using makeup foundations needing long-lasting, non-separating formulas.
Those with rare sensitivities to aluminum compounds.
Individuals preferring creamy lotions with stable textures.
Individuals preferring fully natural or metal-free formulations.
Users with acne-prone skin due to its non-comedogenic profile.
People experiencing contact reactions to fatty acid derivatives.

Safety Notes

  • Assessed as safe for cosmetic use by regulatory reviews.
  • Presents low risk of skin irritation in typical concentrations.

Frequently Asked Questions about Aluminum/Magnesium Hydroxide Stearate

What does it do in skincare products?

Controls viscosity for better texture and stabilizes emulsions to prevent separation.

Is it safe for daily use?

Yes, recognized as safe in cosmetics with low hazard potential.

Does it cause acne?

No, it has a comedogenic rating of 0.