Keratin is a natural fibrous protein that serves as a fundamental building block of the skin, hair, and nails. Its primary role is to provide strength, protection, and elasticity to these tissues, making them resistant to external factors and mechanical damage. Over time, the natural production of keratin decreases, which affects the quality and resilience of hair and nails. Hair can become thinner and more brittle, while nails often weaken and are more prone to breaking. The skin also loses elasticity and becomes more susceptible to damage.
In cosmetics, keratin is most commonly used in hair care products and treatments aimed at restoring damaged strands. Products containing keratin also increase the strength of damaged hair fibers, reduce breakage, and improve hair elasticity and shine.