KERATIN

The nail plate consists of 10–20% skin keratins and 80–90% hair keratins.
Hair and nail keratin contain more cystine — a sulfur-based amino acid that defines the protein’s strength.

Types of keratin
Keratin is divided into two types: Type I – acidic, Type II – basic.
Type I keratins form spiral structures; Type II keratins bind them together.
Skin contains 17 types of Type I keratin and 19 types of Type II.
Hair contains 11 types of Type I and 6 types of Type II keratin.

There are also alpha and beta keratin types.
Alpha-keratin is soft and flexible, forming the basis of hair and the epidermal cells of the skin.
Beta-keratin is stronger and forms the structure of nails.

Keratin synthesis
The synthesis of keratin requires various microelements and substances: oxygen, hydrogen, carbon, sulfur, nitrogen, iron, vitamins A, C, and B group.
For the growth, development, and maturation of keratin cells and fibers, the body needs nutrients including silicon, selenium, iron, calcium, magnesium, zinc, and other minerals.

Keratin is synthesized in skin, hair, and nail cells through keratinization — a natural genetic process of gradual keratin production and accumulation in cells.
In skin: keratin is produced by keratinocytes (epithelial cells).
In nails: in nail matrix cells (onychoblasts).
In hair: in the hair follicle (bulb).
Cells divide, move outward, and eventually transform into keratin (horny cells).

Where is keratin located in the hair?
In the middle and outer layers.

Hair structure includes three layers:

• Inner (medulla): contains nitrogen, oxygen, hydrogen, and carbon — transports nutrients.

• Middle (cortex): filled with keratin. Composed of:

  • Cortical cells (from macrofibrils → microfibrils → alpha-keratin spirals of Type I keratin and melanin).

  • Matrix (Type II keratin, water-absorbing, binds cortical cells like cement).
    Cortex defines hair strength.

• Outer (cuticle): several layers of fully keratinized flat cells that used to be part of the cortex. These cells form scale-like tiles that protect the hair.

The outer layer also contains water and lipids for cohesion, reduced friction, protection, and shine.

Hair composition: 90% keratin, 1% pigment, 3–10% water, 6% lipids.

Keratin bonds in hair
Why are they important? They define hair's physical properties.

Three bond types:

1. Hydrogen bonds – weak, along the hair, broken by water and reformed by heat.

2. Ionic (salt) bonds – weak, across the hair, broken by acids/alkalis, restored when pH is normalized.

3. Disulfide bonds – strong sulfur-based bonds via cystine. Resistant to water, heat, acids, alkalis — though extreme heat (like flat irons) can damage them.

More cystine = stronger hair.
Cystine deficiency = dryness, brittleness, loss of shine.

What destroys keratin?

• Coloring, bleaching, frequent chemical exposure

• High temperatures (irons, dryers, sun)

• Vibrations (nails), incorrect manicure, solvents

• Illnesses, inflammation (vitamin depletion)

• Vitamin deficiencies

Sources of keratin
Amino acids = structural units of keratin → come from protein-rich food (animal and plant):

• Best for keratin: eggs, meat (lamb, beef, veal, liver), poultry, milk, cheese, fish (salmon), seeds, grains, legumes, onions, garlic, etc.

• Vitamin C: helps absorb proteins (citrus fruits, rosehip, sea buckthorn, parsley).

• Vitamin B6: helps produce cystine (nuts, garlic, pomegranate, chicken, liver, tuna).

• Biotin (B7): enzyme function in keratin synthesis (eggs, liver, salmon, soy, spinach).

• Vitamin A: supports keratin production (pumpkin, carrots, sweet potato, mango, kale).

• Iron: delivers oxygen to cells (meat, shrimp, apples, lentils).

• Sulfur: essential for amino acid synthesis (pork, eggs, dairy, legumes, cabbage, asparagus).

• Zinc: regulates keratinocytes (oysters, red meat, seeds, nuts, lentils).

Keratin in cosmetics
Widely used in hair and nail cosmetics.

• Animal-derived: from wool, used in hair treatments (keratin straightening), nail strengthening.

• Plant-derived: from corn, wheat, soy, rice — found in shampoos, conditioners, nail products.

Whole keratin molecules work on the surface.
Hydrolyzed keratin penetrates inside the hair or nail and restores damage.

Keratin hair care
Keratin care restores and maintains hair beauty using various keratin-based products: shampoos, masks, conditioners, sprays, etc.
Effects:

• Surface repair: fills damage, reduces porosity

• Smooths hair surface, easier combing

• Internal repair: strengthens structure

• Moisture retention

• Increases elasticity, strength

• Removes split ends

• Restores shine and smooth curl shape

Who is it for?
Suitable for all hair types. Especially recommended for damaged, brittle, dull hair — to restore strength and resilience.

Keratin cosmetics
Available in our online store in a wide range of formats and purposes.