What it is
In the register’s words: “Magnesium Sulfate is the inorganic salt.”
- EU register name (INCI)
- MAGNESIUM SULFATE
- CAS number
- 7487-88-9; 10034-99-8 (heptahydrate) ; 18939-43-0
- EC number
- 231-298-2
What the register lists it for
These are the uses the European Commission’s CosIng register lists for Magnesium Sulfate in any cosmetic, hair roles first. They say why a maker might add it, not what it does in one formula, and they aren’t a safety rating.
- Bulking
-
Adds volume to a product without reacting with anything.
Register definition: “Non-reactive (chemically inert), solid ingredients that dilute other solids and/or increase the volume of cosmetic products.”
Where it sits on each label
US labels list ingredients from most to least, except that those at 1% or less may follow in any order. A name near the top is a large part of the formula. A label doesn’t mark where the 1% point falls, so further down, the order says little about how much is in it.
- Clarifying shampoos 1 label First five names: 0 of 1 Clarifying shampoos without it
- Stylers 1 label First five names: 0 of 1 Stylers without it
- Protein treatments 2 labels First five names: 2 of 2 Protein treatments without it
- Curl refreshers 1 label First five names: 1 of 1 Curl refreshers without it
Every label, product by product (5)
- Ouidad Water Works Clarifying Shampoo Clarifying shampoo 17th of 33 names
- Jessicurl Confident Coils Styling Solution Styler 9th of 13 names
- ApHogee Two-Step Protein Treatment Protein treatment 4th of 29 names
- Redken Extreme CAT Protein Reconstructing Treatment Protein treatment 3rd of 16 names
- Jessicurl Awe Inspiraling Spray Curl refresher 3rd of 7 names
Each line runs from the first name on a label to the last; a dot is where this ingredient sits. Makers change formulas now and then; if the list on your bottle differs, go by your bottle.
Your next step
Other bulking ingredients on these labels
- Silk Powder 2 labels
Updated · The name, numbers and uses come from the European Commission’s CosIng entry (CC BY 4.0); we write the uses in US spelling and put the hair ones first. The labels are each maker’s own. The order rule is the FDA’s Cosmetics Labeling Guide. All our sources are on the Sources page.