What it is
In the register’s words: “Betaine is the zwitterion (inner salt).”
- EU register name (INCI)
- BETAINE
- CAS number
- 107-43-7/ 590-47-6
- EC number
- 203-490-6/ 209-684-7
What the register lists it for
These are the uses the European Commission’s CosIng register lists for Betaine 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.
- Hair conditioning
-
The register’s hair role for ingredients that make hair feel softer, smoother or easier to comb. Most conditioners, masks and leave-ins list several.
Register definition: “Enhancing the appearance and feel of hair. Leaving the hair easy to comb, supple, soft and shiny and/or imparting volume, lightness, gloss, texture, etc.”
- Humectant
-
Holds water in the product and on the surface it touches. Glycerin, honey and aloe are common humectants on curly-hair labels.
Register definition: “Retaining and/or preserving the moisture in a product during use.”
- Skin humectant
-
Draws water into the top layers of skin. Glycerin-type ingredients carry it alongside the plain humectant role.
Register definition: “Increasing the water content of the top layers of the skin. Humectants are primarily hygroscopic agents drawing moisture from the surrounding air.”
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.
- Shampoos 2 labels First five names: 0 of 2 Shampoos without it
- Rinse-out conditioners 2 labels First five names: 2 of 2 Rinse-out conditioners without it
- Deep conditioners 1 label First five names: 1 of 1 Deep conditioners without it
- Leave-in conditioners 2 labels First five names: 0 of 2 Leave-in conditioners without it
- Stylers 1 label First five names: 1 of 1 Stylers without it
- Heat protectants 2 labels First five names: 2 of 2 Heat protectants without it
Every label, product by product (10)
- Curlsmith Essential Moisture Shampoo Shampoo 6th of 28 names
- Curlsmith Fragrance-Free Shampoo Shampoo 6th of 23 names
- Curlsmith Essential Moisture Conditioner Rinse-out conditioner 4th of 33 names
- Curlsmith Fragrance-Free Conditioner Rinse-out conditioner 4th of 29 names
- As I Am Hydration Elation Intensive Conditioner Deep conditioner 3rd of 29 names
- As I Am Leave-In Conditioner Leave-in conditioner 14th of 25 names
- Mielle Pomegranate & Honey Leave-In Conditioner Leave-in conditioner 16th of 27 names
- As I Am Curling Jelly Styler 5th of 19 names
- OLAPLEX Nº.9 Bond Protector Nourishing Hair Serum Heat protectant 3rd of 31 names
- Bouclème Curl Defence Spray Heat protectant 5th of 35 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 hair conditioning ingredients on these labels
- Glycerin 131 labels
- Panthenol 72 labels
- Cocos Nucifera (Coconut) Oil 69 labels
- Behentrimonium Methosulfate 38 labels
- Caprylyl Glycol 37 labels
- Behentrimonium Chloride 34 labels
- Cocamidopropyl Betaine 34 labels
- Simmondsia Chinensis (Jojoba) Seed Oil 34 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.