Arginine
Amino acid; participates in collagen synthesis and acts as a pH regulator replacing synthetic alkalis. In skin formulas works as a mild humectant.
Evidence by route
Topical application
Safe pH regulator and auxiliary humectant. Standalone clinical skin effects are limited.
- CIR Expert Panel. Int J Toxicol. 2006;25 Suppl 1:95-107.
How to read tiers A–F
- CWeak evidence. In vitro data, open-label studies, or expert consensus
Tolerability and safety
- Irritation potential
- Low
- Allergen risk
- Low
- Pregnancy
- Safe
- Suitable for
- Normal, Dry, Oily, Combination, Sensitive
About this ingredient
Arginine is a conditionally essential α-amino acid. The natural substrate of NO synthase (NOS) – produces nitric oxide NO, which dilates vessels. In skin it participates in collagen, elastin, and urea synthesis. Mechanism. Several roles: humectant (binds water through free amino groups), pH adjuster (replaces synthetic alkalis in eco-formulas), collagen synthesis substrate (via L-arginine → L-citrulline → L-proline → collagen). At high topical concentrations (>5%) NO generation may improve microcirculation – a theoretical 'anti-dullness' rationale. Where applied. Anti-aging serums and creams (0.5–5%), eye-area creams, brightening masks, haircare. In Spain – Sesderma Acglicolic, Mesoestetic, Skeyndor. Evidence base. Few skin RCTs. Manufacturer in vitro studies show stimulation of collagen synthesis in fibroblast culture. Insufficient human clinical endpoints. Safety. CIR confirmed safety of amino acids in cosmetics. Hypoallergenic, non-irritating, non-comedogenic. Pregnancy and lactation – safe. Oral arginine in pregnancy is used for preeclampsia correction under physician supervision. Topical use – unrestricted. Functional role. A multitasking amino ingredient with a plausible mechanism and weak clinical base. Part of the NMF amino acid complex, not a standalone active.
Frequently asked questions
Is Arginine safe during pregnancy?
Arginine is considered safe during pregnancy at typical cosmetic concentrations. Systemic absorption through the skin is minimal.
What skin types is Arginine for?
Arginine suits: normal, dry, oily, combination, sensitive.
What is Arginine and what does it do in cosmetics?
Amino acid; participates in collagen synthesis and acts as a pH regulator replacing synthetic alkalis.
What's the INCI name for Arginine?
The INCI name is Arginine. It may also appear as: L-Arginine.
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Ingredients in the same category
Arginine HCl, Arginine PCA, Ascophyllum Nodosum Extract, Asparagine, Decylene Glycol, Hydrogenated Glyceryl Palmate, Methionine, Rosa Damascena Flower Water
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