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

DIHYDROXYPROPYL CYSTINE

Safety grade: A

This amino acid derivative is derived from a natural protein building block and works to strengthen and condition hair and skin. It helps improve elasticity and moisture retention, making products feel smoother and more resilient. You'll often find it in hair care and anti-aging formulations.

Graded using: COSING.

Last verified: June 9, 2026