What Type of Keratin is Hair?
Hair is made of hard keratin. This type of keratin, unlike soft keratin found in skin, is characterized by its high sulfur content. This higher sulfur content contributes to the strength and resilience of hair. Hard keratin is also found in other structures like claws and nails.
Keratin is a fibrous protein that forms the structural basis of many animal tissues. In humans, alpha-keratins are the primary type of keratin found in hair, nails, and the epidermis (outer skin layer). These alpha-keratins are further categorized into type I and type II keratins, both contributing to hair's structure. The specific combination of these types determines the properties of the hair, including its texture and strength. For example, the type I keratins in hair are numbered Ha1–Ha9.
- Hard Keratin: High sulfur content, greater strength and resilience. Found in hair, nails, claws, and horns.
- Alpha-keratin: The prevalent type of keratin in human hair and the wool of other mammals. It has a fibrous structure.
Keratin Treatments and Hair
Keratin treatments are popular cosmetic procedures aiming to improve hair's appearance by smoothing and reducing frizz. These treatments often involve applying products containing keratin proteins or keratin-like compounds to the hair. While these treatments work on various hair types, the underlying principle is essentially supplementing the hair's existing keratin structure, improving its overall strength and smoothness.
The following sources confirm these details:
- Cleveland Clinic states that alpha-keratin is found in the hair, epidermis, horns, and nails of mammals.
- Verywell Health mentions that alpha-keratins are the exclusive form of keratin in humans and the wool of other mammals.
- Wikipedia confirms hair keratin is found in hair and nails.
- A variety of additional sources mention the use of keratin treatments to improve hair health and appearance, suggesting the importance of keratin in hair structure.
