Here's why:
* Keratin is the protein that makes up hair. It's the building block, but it doesn't determine the color.
* Hair color is determined by melanin. This pigment is produced by melanocytes in hair follicles.
* Different types of melanin create different hair colors. Eumelanin (brown/black) and pheomelanin (red/blonde) are the main types.
However, hair treatments that contain keratin can indirectly affect hair color:
* Keratin smoothing treatments: These treatments can make hair appear slightly darker because they seal the cuticle, which can make the hair more reflective and thus appear richer in color.
* Keratin hair products: Some products might contain ingredients that slightly enhance or change the color of the hair, but these are often temporary and not the main function of keratin.
To permanently change your hair color, you need to use hair dye. Hair dye works by breaking down the existing melanin and depositing new pigment.
In summary: While keratin is a fundamental component of hair, it does not influence hair color directly. However, some keratin treatments can make hair appear slightly darker due to increased shine and reflection.