Calcium Ascorbate
INCI: Ester-C
Reviewed by Daisy · Last updated 18 Aug 2026
Also known as: Ester-C, Ascorbic Acid, Vitamin C, Ascorbyl Palmitate, Magnesium Ascorbyl Phosphate
Buffered Vitamin C with mineral benefits
At a glance
Addresses
EWG Safety Score
What Is Calcium Ascorbate?
Calcium Ascorbate is a mineral salt of ascorbic acid that combines Vitamin C with calcium. This buffered form has a more neutral pH than pure ascorbic acid, making it gentler on sensitive skin and less acidic to formulate with.
While providing Vitamin C's antioxidant benefits, this form also delivers a small amount of calcium. It offers good stability and tolerability for those who find pure L-ascorbic acid too irritating.
Benefits for Your Skin
Clinical Evidence & References
Published Research
-
Calcium ascorbate: Stable vitamin C derivative Nutrients, 2017
Regulatory information
Standardised cosmetic-ingredient identifiers used by regulators.
Show identifiers
- INCI Name
- CALCIUM ASCORBATE
- EC Number
- 227-261-5
- Function
- Antioxidant, Skin Conditioning
Frequently Asked Questions
From the Clinic
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Articles About Calcium Ascorbate
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