A hair keratin treatment is a professional hair-smoothing process designed to reduce frizz, add shine, and make hair easier to manage. Keratin is a natural protein already found in hair, skin, and nails. Over time, heat styling, coloring, pollution, and environmental damage reduce the keratin in your hair, leading to dryness and frizz. The treatment replenishes lost keratin and coats the hair shaft, helping strands look smoother and healthier.