Trimethylglycine, an osmolyte used in moisturizing and cleansing formulas.
Sources: 1Trimethylglycine, Glycine betaine
Not assessed
No pregnancy- or breastfeeding-specific assessment has been completed for this record. A cosmetic safety review is not a pregnancy rating.
Limited evidence
Betaine
What it does
Helps manage water in a formulation and has been studied for reducing irritation from particular detergent systems.
Sources: 1Good for
- Hydrating formulas
- Mildness-focused cleansers
How to use it
Use the finished serum, cleanser or moisturizer as directed. This ingredient does not require a separate routine step.
Sources: 1Who should be careful
A betaine-containing cleanser can still irritate because of its full surfactant system or other ingredients.
Sources: 1Pairs well with
No supported pairings have been documented for this record.
Usage, safety and formulation details
Mechanism of action
Its zwitterionic structure supports osmolyte behavior. It is not the surfactant cocamidopropyl betaine.
Sources: 1Potential adverse effects
Stinging or contact reactions are possible in an individual product; many other formula components can also be responsible.
Sources: 1Formulation considerations
Any mildness benefit is specific to the tested cleansing system and concentration.
Sources: 1Pregnancy and breastfeeding
Not assessed
No pregnancy- or breastfeeding-specific assessment has been completed for this record. A cosmetic safety review is not a pregnancy rating.
Safety tags
- Fragrance allergen
- Not assessed
Not separately assessed in this draft.
- Essential oil
- Not assessed
Not separately assessed in this draft.
- Drying alcohol
- Not assessed
Not separately assessed in this draft.
- May irritate sensitive skin
- Not assessed
Not separately assessed in this draft.
What remains uncertain
- Exact concentration, final pH and the full composition of any unprovided finished product
Clinical evidence and research (1 studies)
Clinical evidence
Evidence for its main benefitLimited evidence
A cited study is entered below. Its formulation, exposure and limitations must be considered before applying the results to another product.
Sources: 1Betaine and detergent irritation: human experimental study
- Design
- Experimental human detergent-irritation evaluation
- Population
- Not extracted into this record
- Studied concentration
- Not extracted into this record
- Duration
- Not extracted into this record
Betaine's effects were assessed in particular detergent exposures.
Limitations: Mildness findings do not establish the same benefit for every cleanser or for betaine alone.
Small clinical studySources: 1Regulation and ingredient label names
Regulatory information
No jurisdiction-specific assessment is recorded. An inventory listing is not blanket approval.
Names on ingredient lists
betaine
Chemical identity and molecular structure
Chemical information
Chemical structure
| Detail | Value | Source |
|---|---|---|
| PubChem CID | 247 | PubChem compound 247: chemical identity |
| molecular formula | C5H11NO2 | PubChem compound 247: chemical identity |
| molecular weight | 117.15 g/mol | PubChem compound 247: chemical identity |
Content updated 9 November 2026.
Sources (2)
Scientific sources
- Betaine and detergent irritation: human experimental studyhuman tolerance study · 2003
- PubChem compound 247: chemical identitychemical identity
Keep exploring: ingredient library or build your skincare routine.


