L-Ascorbic Acid
INCI: Ascorbic Acid
Reviewed by Daisy · Last updated 14 Aug 2026
Also known as: Ascorbic Acid, Vitamin C, Pure Vitamin C
Potent antioxidant and form of vitamin C Can improve the appearance of signs of ageing
EWG Safety Score
What Is L-Ascorbic Acid?
Form of vitamin C that is a potent antioxidant and skin-soothing agent. Abundant research demonstrates that l-ascorbic acid improves the appearance of multiple signs of ageing, including fine lines, wrinkles, skin thinning and skin laxity. This form of vitamin C promotes skin longevity and helps protect skin’s collagen. In addition, it helps brighten an uneven skin tone. L-ascorbic acid is often labelled as the INCI compliant “ascorbic acid” on ingredient lists, but there is no difference between the two - they refer to the same ingredient.
Frequently Asked Questions
From the Clinic
Not sure what your skin actually needs?
Two minutes, a few questions, and we’ll point you at what matters — no guesswork.
Take the skin quizRelated Ingredients
Kojyl Glucoside
A gentle antioxidant derived from kojic acid, designed to protect and calm the skin
Kojyl Methylenedioxycinnamate
A plant-derived antioxidant that helps protect skin from environmental damage
Kunzea Pomifera Seed Oil
An antioxidant-rich plant oil that conditions and protects the skin barrier
Lactobacillus/Portulaca Oleracea Ferment Extract
Created by fermentation of the purslane plant Has antioxidant benefits
Lady's Thistle (Milk Thistle) Extract
Potent antioxidant Skin-soothing and restorative properties
Larix Sibirica Wood Extract
A wood extract with purifying and antioxidant properties for scalp and skin health
Articles About L-Ascorbic Acid
Learn more about this ingredient with our expert guides and articles.
What Is a Vitamin C Serum Actually Doing to Your Skin?
Ask ten people what vitamin C serum does and you’ll get ten different answers — "brightening", "anti-ageing", "for dark spots" — and none of them are wrong exactl
Read article
SkinCeuticals UK: The Complete Brand Guide
Your complete guide to SkinCeuticals in the UK: the antioxidant science, hero vitamin C serums like C E Ferulic, and how to choose where to start.
Read article
The Best Vitamin C Serums UK (2026): A Buyer's Guide by Form, Strength and Skin Type
A practical guide to choosing the best vitamin C serum for your skin type and concern, from gentle daily antioxidants to high-strength brightening formulas.
Read article
Professional Ingredient Protocols
Professional skincare protocols using clinical-strength ingredients. Expert guidance for advanced skincare routines.
Read articleLearn More About Skincare Ingredients
Explore our comprehensive ingredient glossary to understand what's in your products.
Browse All IngredientsShop Our Products
Find professional skincare solutions at Skintique.