L-Ascorbic Acid • Ascorbyl Glucoside • Tetrahexyldecyl Ascorbate
Vitamin C
An antioxidant powerhouse that brightens, defends against pollution, and gradually fades dark spots.
Updated April 26, 2026 • General skincare education, not medical advice.
What is vitamin c?
Vitamin C neutralizes free radicals generated by UV and pollution, making it the ideal morning companion to SPF. It also blocks an enzyme called tyrosinase, which is the reason it fades pigmentation over time.
Key benefits
- Brightens dull, tired-looking skin
- Fades hyperpigmentation and post-acne marks
- Provides antioxidant protection against environmental damage
- Stimulates collagen for firmer-looking skin
- Complements daily SPF in a morning routine
Who should use it?
All skin types — choose gentler derivatives (Ascorbyl Glucoside, THD Ascorbate) if you are sensitive. L-Ascorbic Acid at 10–20% is a common range for visible brightening benefits.
How to use vitamin c
- Apply in the morning on clean, dry skin.
- Use 2–4 drops of serum for the face and neck.
- Wait 60 seconds, then follow with moisturizer and SPF 30+.
- Store in a cool, dark place — L-Ascorbic Acid oxidizes in sunlight.
Pairs well with
- • Vitamin E
- • Ferulic acid
- • SPF
- • Hyaluronic acid
Use with caution
- • Retinol (same routine — use AM/PM instead)
- • Benzoyl peroxide
Frequently asked questions
How do I know if my vitamin C has oxidized?
A fresh L-Ascorbic Acid serum is clear to pale yellow. If it turns deep orange, brown, or cloudy it has oxidized and should be replaced — it will not be effective and may stain your skin and pillowcase.
Can I use vitamin C with retinol?
Yes, but in separate routines. Use vitamin C in the morning for antioxidant defense, and retinol at night for repair. Layering them at the same time can cause irritation.
What is the best percentage of vitamin C?
For L-Ascorbic Acid, many formulas sit in the 10–20% range. Higher percentages can be more irritating, so sensitive skin often does better with gentler derivatives or lower strengths.
Helps with
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