The Beauty & Personal Care Brand Builder Series

Ingredient Deep Dive

Magnesium Sulfate

The Beauty & Personal Care Brand Builder Series

Ingredient Deep Dive

Magnesium Sulfate

The Mineral Salt & Emulsion Stabilizer

Magnesium Sulfate (Epsom salt) is a simple mineral salt used in cosmetics mainly as a stabilizer for water-in-oil emulsions and a viscosity/texture aid.

As an electrolyte it locks water-in-oil creams into a stable structure, and it also contributes a mineral, bath-salt story to soaks and scrubs.

Quick Insights

Ingredient Rating:

GOOD

Type of Ingredient:

Texture Enhancer

Intended Function:

A mineral salt used to stabilize water-in-oil emulsions and as a bath-mineral base.

Common Applications:

Used in moisturizers, creams and cleansers and treatment formulas.

Target Audience:

Formulators building w/o creams and sunscreens, or bath soaks and salt scrubs.

Also Known As:

Magnesium Sulfate, Epsom Salt, Magnesium Sulphate

Private Label Formulas

🇺🇸 MADE IN USA | 🚀 READY TO LAUNCH

Sea Salt Spray

Benefits of Magnesium Sulfate

A mineral salt that stabilizes water-in-oil emulsions and adds bath-mineral appeal.

W/O Stabilization: Electrolyte action stabilizes water-in-oil creams and lotions.
Texture Control: Helps set viscosity and body in emulsions.
Mineral Story: Brings a familiar Epsom-salt, bath-mineral appeal.
Bath & Scrub Base: A classic ingredient for soaks and salt scrubs.
Simple & Safe: A well-understood, widely used mineral.

How It Works

In water-in-oil systems, dissolved Magnesium Sulfate provides electrolytes that screen charges and lock water droplets firmly within the oil phase, greatly improving the emulsion’s stability; in bath products it simply dissolves to deliver its familiar mineral soak.

Formulating with Magnesium Sulfate

Magnesium Sulfate is dissolved in the water phase at low levels to stabilize w/o emulsions, or used at high levels as the base of bath soaks and scrubs. Observe good manufacturing and preservation practice.

Safety Analysis

Magnesium Sulfate is well tolerated at typical use levels with a good safety profile in finished cosmetics. As always, substantiate the finished product’s safety (e.g. patch / HRIPT testing) in line with MoCRA requirements.

References

https://incidecoder.com/ingredients/magnesium-sulfate

https://cosmeticsinfo.org/ingredient/magnesium-sulfate/

https://cosmeticanalysis.com/cosmetic-ingredients/magnesium-sulfate

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