Proline
Non-essential amino acid. Important component of collagen; in skincare part of amino-acid complexes.
Evidence by route
Topical application
Safe collagen-precursor amino acid.
How to read tiers A–F
- BLimited evidence. One RCT or several controlled studies with limitations
Tolerability and safety
- Irritation potential
- Low
- Allergen risk
- Low
- Pregnancy
- Safe
- Suitable for
- Normal, Dry, Oily, Combination, Sensitive
About this ingredient
Proline (L-Proline) is a non-essential amino acid. An important collagen component (12-14% of all skin collagen) and elastin. In skin synthesised from glutamic acid. Where applied. Serums and creams with amino-acid complexes as NMF, anti-aging products (0.05-0.5%). Common in mature-skin lines. Evidence base. Topical RCTs of standalone proline effect on skin in humans are limited. Most data are in vitro: adding proline to fibroblast cultures increases in vitro collagen synthesis. Translating that to topical cosmetics is speculative (proline penetrates epidermis poorly). Marketing positioning outpaces evidence. Safety. CIR confirmed safety at cosmetic concentrations. Hypoallergenic. Non-comedogenic. Pregnancy and lactation – safe.
Frequently asked questions
Is Proline safe during pregnancy?
Proline is considered safe during pregnancy at typical cosmetic concentrations. Systemic absorption through the skin is minimal.
What skin types is Proline for?
Proline suits: normal, dry, oily, combination, sensitive.
What is Proline and what does it do in cosmetics?
Non-essential amino acid.
What's the INCI name for Proline?
The INCI name is Proline. It may also appear as: L-Proline.
See Proline in a product composition right on the store page
The Evigrade extension adds an evidence panel to iHerb, Sephora, Druni and 12 more stores. This ingredient and every other one in the product show evidence-tier, allergen risk and pregnancy/lactation flags at a glance.
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