Acids

Sodium Sulfite

Reviewed by Daisy · Last updated 18 Aug 2026

Reducing agent that alters the structure of hair | Can be used as a preservative in cosmetic formulations

What Is Sodium Sulfite?

Sodium sulfite is a reducing agent that alters the structure of hair. It can also be used as a preservative in cosmetic formulations. If used in high concentration, there’s potential for sodium sulfite to sensitize skin, but in lower amounts this is a non-issue.

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