Ingredient glossary
Betaine
On your shelf ✓What Betaine does for your skin, who it suits, and what to watch for.
INCI: Betaine · Also: Trimethylglycine
In short: Betaine delivers hydration and osmoprotection, suits dry and sensitive skin best, and the evidence behind it is moderate.
- What it does
- Hydration, osmoprotection
- Best for
- Dry, Sensitive skin
- Evidence
- Moderate
- How long
- Straight away
The molecule
The Glow take
Genuinely worth a spot in your routine.
When your goal is deep, lasting hydration, Betaine pulls genuine weight, with a solid amount of evidence behind it. It tends to suit dry skin best.
— Maya
What it does
- hydration
- osmoprotection
moderate evidenceIn vitro and cosmetic studies suggest betaine reduces irritation and supports hydration by acting as a cellular osmoprotectant.
On a label: usually effective at 1-5%.
Who it's for, and who should skip it
Tends to suit
- dry
- dehydrated
- sensitive
Approach with care
No specific group flagged to avoid it.
- Clogs poresLow
- Irritation riskLow
How it fits each skin type
- DrySuits
- CombinationNeutral
- OilyNeutral
- SensitiveSuits
Where it fits in your routine
This one works on contact — there is nothing to wait for.
What that covers, and what it does not
Measured on: Corneometer stratum corneum hydration.
Trimethylglycine is a strongly hygroscopic zwitterion, so the surface water-binding component of its effect is present on application — physical, not remodelling — and that is what this row times. The other half of its story is not: the osmoprotection and anti-irritant claims rest on in-vitro cell work, which the base's own evidence notes acknowledge, and no human study reports when an irritation or barrier endpoint changes with betaine at the 1-5% used in cosmetics. So the hydration bucket is mechanism-derived and the anti-irritant one is genuinely untimed.
Mechanism only for hydration; in-vitro osmoprotection literature for the second claim. No single-ingredient human time-course study located.
Plays well with
- humectants
- ceramides
Betaine, answered
Is Betaine safe during pregnancy?
Yes. Betaine is considered safe to use during pregnancy and breastfeeding. As with anything, if you are unsure it is worth a quick word with your doctor or midwife.
Who should avoid Betaine?
No specific group is flagged to avoid Betaine. It is well tolerated by most skin. Still, introduce anything new one product at a time.
What concentration of Betaine actually works?
Betaine tends to do its job in the 1 to 5% range. Much lower and it is likely underdosed.
Compare Betaine with
- Hyaluronic acid
- Pro-vitamin B5
- Sodium PCA
- Aloe
- Butylene Glycol
- Propanediol
- Trehalose
- Xylitol
- Hydroxyethyl Urea
- Glycereth-26
- Polyglutamic Acid
- Tremella Fuciformis Extract
- Beta-Glucan
- Hydrolyzed Collagen
- Honey
- Pentylene Glycol
- Crosslinked sodium HA
- Propylene Glycol
- Hydrolyzed hyaluronic acid
- Acetylated Hyaluronic Acid
- Fructooligosaccharides
- Hexylene Glycol
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