Proteins from silkworm silk that film the hair and hold moisture, adding softness and shine. A conditioning effect only.
Silk proteins (fibroin broken into amino acids or small peptides, and sericin, the silk 'gum') attract water and form a light film on the hair. The result is softer, glossier hair that combs more easily until the next wash.
Support comes from ingredient-maker lab tests of gloss, moisture and combing. No trials show effects on hair growth or long-term hair health.