INCI Name
Magnesium Sulfate
Functions
1 Roles
Sustainability
9/10
Category
actives
What It Does
Magnesium Sulfate (MgSO4·7H2O) is an inorganic salt naturally found in mineral deposits and seawater, most famously known as Epsom salt after the town in England where it was first distilled from spring water. In cosmetic formulations, it serves as both a magnesium delivery system and an osmotic agent that draws out impurities while replenishing this essential mineral through the skin. Formulators choose USP-grade coarse crystals for bath products and body treatments because they dissolve slowly, providing sustained release of magnesium ions that help relax muscles, reduce inflammation, and support skin barrier function while also acting as a natural exfoliant in scrub formulations.
Technical Properties
pH Range
5.5-7.0
Optimal working range
Ionic Charge
anionic
Molecular charge type
Viscosity Effect
neutral
Impact on formula thickness
Foaming Ability
none
Lather generation
Ingredient Compatibility
Known Interactions
Calcium and Magnesium compete for absorption at high doses. While they can be combined at moderate levels, high-dose formulations should separate them or use chelated forms.
Sustainability Profile
Sustainability Score
Biodegradability
readily biodegradable
Source
mineral
Feedstock
naturally occurring mineral deposits or seawater extraction
Available Variants
3 forms available
Coarse Crystals (USP Grade)
Fine crystalline powder (pharmaceutical grade, 40-60 mesh)
Standard
Quick Reference
- Full INCI Name
- Magnesium Sulfate
- Common Name
- Epsom Salt
- CAS Number
- 7487-88-9
- Category
- actives
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