Keratin in Haircare

Keratin is a fibrous structural protein that forms the primary building block of hair, skin, and nails. In hair, keratin makes up approximately 90% of its composition, providing strength, elasticity, and protection. It is a complex protein, rich in the amino acid cysteine, which forms disulfide bonds. These bonds are crucial for hair's structural integrity, contributing to its resilience and shape.

Origin and Chemistry

Naturally, keratin is produced by keratinocytes in the epidermis. For cosmetic applications, keratin is typically sourced from animal by-products, most commonly wool, horns, or feathers. These larger, insoluble keratin proteins are then hydrolyzed (broken down with water) into smaller, more manageable peptides and amino acids. This process results in "hydrolyzed keratin," "keratin amino acids," or "keratin peptides," which are more easily absorbed by the hair shaft.

What it Does on Hair and Scalp

When applied topically in haircare products, hydrolyzed keratin can temporarily penetrate the outer layers of the hair strand, known as the cuticle. It helps to fill in gaps and rough spots on the cuticle, leading to a smoother, more uniform surface. This action effectively reduces frizz, enhances shine, and improves the hair's overall texture. By reinforcing the hair's structure, keratin can also enhance its elasticity and tensile strength, making it less prone to breakage.

On the scalp, keratin plays a role in maintaining the skin barrier. While its direct benefits for scalp conditions when applied topically are less pronounced than for the hair shaft, a healthy scalp environment can indirectly benefit from products that support its natural protein structure.

Keratin Benefits

• Strengthens Hair: Keratin, particularly hydrolyzed keratin, helps to reinforce the hair's internal structure by temporarily binding to damaged areas. This action increases tensile strength and reduces susceptibility to breakage, benefiting those with weak, brittle, or chemically treated hair.
• Smooths Frizz: By filling in gaps and rough spots on the hair cuticle, keratin creates a smoother, more uniform surface. This reduces friction between hair strands, leading to a significant reduction in frizz and flyaways, especially beneficial for those with unruly or damaged hair.
• Enhances Shine: The smoothing effect on the cuticle allows light to reflect more evenly off the hair surface, resulting in increased luster and a healthy-looking shine. This is particularly advantageous for dull or lacklustre hair.
• Improves Elasticity: Keratin can help restore some of the hair's natural elasticity by strengthening the protein matrix. This makes hair more pliable and less likely to snap when stretched, benefiting those with brittle hair.
• Repairs Damage: While not a permanent fix, keratin treatments and products can temporarily patch up microscopic damage on the hair shaft caused by heat styling, chemical treatments, and environmental stressors. This provides a cosmetic improvement in the hair's appearance and feel.
• Protects Against Environmental Stressors: By forming a protective layer over the hair cuticle, keratin can help shield hair from further damage caused by UV radiation, pollution, and harsh weather conditions, making it beneficial for anyone regularly exposed to these elements.

Who Benefits Most

Individuals with chemically treated hair (colored, permed, relaxed), heat-damaged hair, or naturally fine, weak, and brittle hair often see the most significant improvements from keratin-containing products. Those seeking to reduce frizz, enhance shine, and improve overall manageability will also find it beneficial.

Who Should Avoid It

While generally safe, individuals with extremely fine hair might find that excessive use of products with high concentrations of heavy keratin can lead to a slightly stiff or weighed-down feeling. In extremely rare cases, individuals with specific sensitivities may experience minor scalp irritation, though this is more often related to other ingredients in the formulation.

Common Concentrations

In cosmetic formulations, hydrolyzed keratin is typically found in concentrations ranging from 0.1% to 5%. Higher concentrations are generally reserved for intensive treatments or dedicated reparative products. The effectiveness is not solely dependent on concentration but also on the molecular weight and specific type of hydrolyzed keratin used.

Safety and Regulatory Notes

Keratin itself is considered safe for cosmetic use. The main safety considerations often revolve around the formulation of "keratin treatments" or "Brazilian blowouts" performed in salons. These professional treatments often contain formaldehyde or formaldehyde-releasing chemicals, which are used to cross-link the keratin to the hair and create a long-lasting straightening effect. Formaldehyde is a known irritant and carcinogen. However, consumer haircare products containing hydrolyzed keratin do not contain these chemicals and are generally safe for home use. Watermans products contain only safe, consumer-friendly forms of keratin.

Product Categories Where It Appears

Keratin is a versatile ingredient found in a wide array of haircare products, including:

• Shampoos and Conditioners: To provide daily strengthening and smoothing benefits.
• Leave-in Treatments: For continuous repair, frizz control, and protection.
• Hair Masks: Intensive treatments designed for deep conditioning and damage repair.
• Styling Products: To add structure, reduce frizz, and enhance shine.
• Serums and Oils: For targeted smoothing and protection, particularly for split ends.

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Did you know?

• Hair is primarily composed of keratin, making up about 90% of its structure.
• The keratin in our hair is a 'dead' protein, meaning it's no longer living tissue.
• Different types of keratin exist, with specific forms contributing to the varying textures of hair.