L-Ascorbic Acid / Ascorbyl Glucoside / MAP / THDA
The gold-standard antioxidant for skin. L-Ascorbic Acid neutralises free radicals, inhibits tyrosinase to fade hyperpigmentation, is essential for collagen biosynthesis, and provides measurable photoprotection under SPF. Derivatives like Ascorbyl Glucoside and Tetrahexyldecyl Ascorbate are more stable and gentler. Results visible in 4–12 weeks.
At these concentrations this ingredient should appear above the 1% line on the INCI list. If you see it listed after preservatives or fragrance allergens, the dose is likely too low to work as marketed.
AM serum before SPF. L-Ascorbic Acid 10–20% most potent (requires pH <3.5). Ascorbyl Glucoside gentler for sensitive skin at any pH. Always follow with SPF.
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