Vitamin C (L-Ascorbic Acid)
AntioxidantBrighteningVitaminNaturalAlso known as: L-Ascorbic Acid, Ascorbic Acid, LAA, Ascorbyl Glucoside, Sodium Ascorbyl Phosphate, Magnesium Ascorbyl Phosphate
A powerful antioxidant that brightens skin, boosts collagen production, and protects against environmental damage including UV and pollution.
Routine placement
Serum · AM
Time to results
4-6 weeks for brighter tone; 8-12 weeks for dark spots
Brightens skin tone, fades hyperpigmentation, boosts collagen production, protects against UV damage and pollution, evens skin tone.
Apply in the morning before sunscreen. L-Ascorbic Acid works best at pH 2.5-3.5 and concentrations of 10-20%. Store in a dark, cool place to prevent oxidation.
Beginner
5-10%
Intermediate
15%
Advanced
20%
Robust evidence for photoprotection, collagen synthesis, and hyperpigmentation treatment. L-Ascorbic Acid at 10-20% with Vitamin E and Ferulic Acid shows synergistic antioxidant benefits.
Key Studies
Topical vitamin C and the skin (2017)
J Clinical and Aesthetic Dermatology
L-ascorbic acid 10-20% provides photoprotection and stimulates collagen. pH below 3.5 required.
Antioxidants in photoprotection (2003)
J American Academy of Dermatology
Vitamin C + E reduces UV free radical damage by up to 4x.
Vitamin C in dermatology (2013)
Indian Dermatology Online Journal
5-15% ascorbic acid promotes collagen and reduces melanin.
- very sensitive skin (start with derivatives)
Cautions
Can cause tingling or irritation at higher concentrations. L-Ascorbic Acid is unstable and oxidizes easily (turns brown/orange). May not suit very sensitive skin.
Can I use vitamin C and retinol together?
Yes, at different times. Vitamin C AM (photoprotection), retinol PM.
Why did my serum turn brown?
Oxidation from air/light/heat. Replace every 2-3 months. Store dark and cool.
What form is best?
L-ascorbic acid is most effective but unstable. Derivatives are more stable but less potent.
Do I need sunscreen with vitamin C?
Yes. Vitamin C boosts photoprotection but is not a sunscreen replacement.
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