The main component of keratin is α-keratin (alpha-keratin), a type of fibrous structural protein. However, commercial keratin hair treatments often contain additional chemicals, the most prevalent being formaldehyde or formaldehyde-releasing agents. It's crucial to distinguish between the natural protein keratin and the chemical formulations used in hair treatments.
Keratin: The Natural Protein
Keratin is a family of proteins known as scleroproteins, and α-keratin is the specific type found in vertebrate animals. It's the primary building block of:
- Hair
- Nails
- Skin (outer layer)
- Feathers (in birds)
- Horns
- Hooves
- Claws
The amino acid cystine is the most abundant amino acid in keratin, comprising approximately 17.5% of its structure. Other significant amino acids include serine (11.7%) and glutamic acid (11.1%). These amino acids form strong disulfide bonds, contributing to keratin's strength and structural integrity.
Keratin Treatments: Added Chemicals
While keratin itself is a natural protein, many commercially available keratin hair treatments include additional chemicals. These additions are often what causes concern, not the keratin itself. A common additive is formaldehyde, a strong chemical used as a disinfectant and preservative. Formaldehyde is a cause for concern due to its potential health risks. Some manufacturers use formaldehyde-releasing agents instead of formaldehyde directly.
Key Differences to Note:
- Natural Keratin: A protein naturally occurring in hair, skin, and nails. Its primary structural component is α-keratin.
- Keratin Treatments: Commercial products often contain added chemicals, such as formaldehyde or formaldehyde-releasing agents, alongside keratin protein.
It is important to read labels carefully when considering hair treatments marketed as "keratin treatments" to be aware of the presence of potentially harmful chemicals.
