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Hair Conditioning

CYSTINE

CAS 56-89-3 Updated
85

Safety score · 0–100

Good

Derived from EU CosIng regulatory status, PubChem hazard data and published research. How we score.

About

A natural amino acid (two cysteines linked by a disulfide bond) — a building block of keratin. Excellent safety record at cosmetic levels.

Function

ANTISTATIC, HAIR CONDITIONING, FRAGRANCE

Skin benefits

  • Sulfur-containing amino acid
  • Hair structure component
  • Skin/hair conditioning

Known concerns

  • No significant concerns at cosmetic concentrations
  • Mild rare allergy possible

References

EU

EU CosIng database

European Commission cosmetic ingredient registry — regulatory status, restrictions, authorised functions.

Related hair conditionings

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This profile is for educational purposes and does not constitute medical advice. Regulatory status and scientific understanding evolve — always read the physical product label and consult a healthcare professional for personal concerns.