Supports hair brightness, density, and volume by bonding with hair strands Supports healthy, lustrous-looking hair Helps strengthen, nourish, and hydrate hair Our hair is comprised of about 80%-95% keratin. Age-related decline as well as damage from styling products and tools can result in less stable and flexible hair, leaving hair prone to dryness and breakage. Doctor's Best Hydrolyzed Keratin contains KeraGLO hydrolyzed keratin, a beauty-from-within ingredient that helps strengthen and nourish your hair. It is formulated with amino acids to nurture lustrous-looking hair, while also encouraging hair brightness, density and volume by bonding with hair strands. Let your lavish locks shine! Supports Hair brightness, density and volume by bonding with hair strands Healthy, lustrous-looking hair