Ingredient glossary

Arginine

What Arginine does for your skin, who it suits, and what to watch for.

INCI: Arginine · Also: L-Arginine

Minor player

In short: Arginine delivers hydration and conditioning, suits most skin types, and the evidence behind it is limited.

What it does
Hydration, conditioning
Best for
Most skin types
Evidence
Limited
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The molecule

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The Glow take

Nice to have, and nothing to overthink.

Arginine plays a quiet supporting role, rounding out a formula rather than being the reason you buy it.

— Maya

What it does

  • hydration
  • conditioning
  • pH buffer

weak evidenceIts membership of the natural moisturising factor is established. Its size is not: a 2019 study that measured 26 NMF components directly found arginine below the limit of quantification. Added arginine is a supporting player, not a hydration active.

Who it's for, and who should skip it

Tends to suit

  • dry
  • dehydrated
  • normal

Approach with care

No specific group flagged to avoid it.

  • Clogs poresLow
  • Irritation riskLow

How it fits each skin type

  • DrySuits
  • CombinationSuits
  • OilySuits
  • SensitiveSuits

Where it fits in your routine

WhenMorning and evening
Where in the orderOn damp skin, before your moisturizer

Plays well with

Arginine, answered

Is Arginine safe during pregnancy?

Yes. Arginine 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 Arginine?

No specific group is flagged to avoid Arginine. It is well tolerated by most skin. Still, introduce anything new one product at a time.

What concentration of Arginine actually works?

Its concentration is rarely printed on the label, so use the ingredient list as your clue: near the top third it is likely doing real work, near the bottom it is more of a sprinkle.

This, for every label you own

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Sources & how we reviewed this

Last reviewed August 2026. Educational information about a cosmetic ingredient, not medical advice.