L-Ascorbic Acid (Vitamin C)
비타민C (아스코르빈산)
INCI: ASCORBIC ACID
The most potent and evidence-backed form of Vitamin C, but also the most unstable — oxidizes rapidly in air and light, turning orange and losing efficacy. Must be formulated at pH 2.5–3.5 for skin penetration. Klairs and COSRX offer L-AA serums; requires careful storage and conflicts with high-pH ingredients. Best used AM with vitamin E and ferulic acid for stability.
How to read this ingredient
Read L-Ascorbic Acid (Vitamin C) as part of a finished formula
Active is an editorial discovery category, not a regulatory classification or guarantee of efficacy. Read the exact INCI name, formula position, declared amount when available, and finished-product evidence.
- Products shown
- 5
- Formula companions
- 8
- Reviewed interactions
- 3
Published reviewed formulas surfaced on this page
Co-occurrence, not proof of synergy or safety
Only public, source-reviewed guidance appears
Reviewed ingredient relationships
Labels summarize the scope of the reviewed evidence. Formula-supported does not mean every separately formulated product pair is synergistic, compatible, or suitable for every person.
A randomized, investigator-blinded split-face study evaluated a 14-day post-laser regimen using a vitamin C/E/ferulic serum together with a separate resveratrol-containing night serum versus normal saline. This is evidence for that multi-product post-procedure regimen, not an isolated vitamin C–resveratrol effect or a general instruction to layer arbitrary products.
The pair appears in directly relevant finished-formula or regimen evidence. This does not prove that every product pairing is synergistic.
In a specific experimental formula containing 15% L-ascorbic acid, 1% alpha-tocopherol, and 0.5% ferulic acid, ferulic acid improved formula stability and photoprotection in a pig-skin model. This is formulation-specific evidence; it does not establish the same result for arbitrary products layered together, and antioxidants do not replace sunscreen.
Common formula companions
Ingredients frequently mapped in the same products as L-Ascorbic Acid (Vitamin C). This is a formula pattern, not a compatibility or safety claim.
Sources and record context
These links support records surfaced on this page. They do not verify every regional formula, concentration, product claim, or individual result.