Hair is primarily composed of a protein called keratin, which is made up of various amino acids. While hair doesn't contain any specific acids in the conventional sense, cystine is a significant amino acid present in keratin.
Cystine is a sulfur-containing amino acid that plays a crucial role in the structure and strength of hair. It forms disulfide bonds, which link keratin molecules together, creating a strong and resilient fiber.
Therefore, although hair doesn't have a specific acid, cystine, as a component of keratin, is a crucial contributor to hair's structure and properties.
