What it is
Magnesium ascorbyl phosphate is a phosphorylated, magnesium-salt form of ascorbic acid (vitamin C) designed to be more stable and less irritating than pure vitamin C. As a water-soluble derivative it is used in skincare for its antioxidant and skin-conditioning properties and tends to perform best in formulas kept at an appropriate pH. It is included in sunscreens and other products as a vitamin C ingredient rather than as a UV filter.
Safety & warnings
Magnesium ascorbyl phosphate is generally well tolerated and is often chosen as a gentler alternative to pure ascorbic acid, making it suitable for many sensitive-skin users. It is not a recognized fragrance allergen.
Origin & sourcing
It is a synthetically produced derivative of ascorbic acid (vitamin C), modified with phosphate and magnesium to improve stability.
Questions everyone asks
What is magnesium ascorbyl phosphate?
It is a stable, water-soluble form of vitamin C used in skincare as an antioxidant and skin-conditioning ingredient that is gentler than pure ascorbic acid.
Why use it instead of pure vitamin C?
It is more stable and tends to be less irritating than pure ascorbic acid, which makes it easier to formulate with and often better tolerated by sensitive skin.