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Ingredient · INCI reference

Ascorbic Acid

Ascorbic acid is pure vitamin C, a water-soluble antioxidant used to brighten skin and protect it from free radicals.

What it is

Ascorbic acid is the biologically active form of vitamin C. As a potent antioxidant it neutralizes free radicals generated by UV and pollution, and it is widely used to help even skin tone and support a brighter, more radiant look. It is also a cofactor in collagen formation. It is unstable in water and light, so well-formulated products protect it carefully.

Safety & warnings

High-strength vitamin C can sting or irritate sensitive skin, especially at low pH; introduce gradually and patch test.

Origin & sourcing

Produced industrially, commonly from glucose via fermentation and chemical steps.

History

Vitamin C was isolated and characterized in the early 1930s, work that was later recognized with a Nobel Prize.

Questions everyone asks

What does vitamin C do in skincare?

It is an antioxidant that helps defend against free radicals and supports a brighter, more even-looking complexion.

Why does my vitamin C product turn yellow or brown?

Pure ascorbic acid oxidizes when exposed to air and light, which can darken it and reduce its potency.

Sources & references

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