SH-POLYPEPTIDE-121 is graded A (Safe) by Expert·ING, based on COSING regulatory data.

SH-POLYPEPTIDE-121

Safety grade: A

This plant-derived protein helps strengthen and condition hair by forming a protective coating on each strand. It works to reduce frizz, improve shine, and enhance overall hair texture, making it a common choice in shampoos, conditioners, and hair treatments.

Graded using: COSING.

Last verified: June 9, 2026