DIMETHICONOL CYSTEINE is graded A (Safe) by Expert·ING, based on COSING regulatory data.

DIMETHICONOL CYSTEINE

Safety grade: A

This is a silicone-based ingredient combined with cysteine, an amino acid found in hair. It works to coat and smooth the hair surface while helping to strengthen and protect it.

This ingredient conditions hair by coating the hair shaft to reduce frizz, improve shine, and enhance softness while the cysteine component helps fortify and protect hair structure.

Graded using: COSING.

Last verified: May 26, 2026