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Article: Hair: what is keratin?

La kératine est une protéine essentielle qui compose le cheveu.

Hair: what is keratin?

Hair is made of keratin, an essential protein that helps strengthen and protect the hair fiber.


What is keratin?

Keratin is a natural insoluble protein composed of amino acids. It is synthesized using hair cells called “keratinocytes”. They are supplied by blood from the hair papilla.

Keratin is the main substance of hair, in fact, it contains more than 95%. The rest consists of water, pigments and lipids.

Keratin protein provides shine, suppleness and strength to the hair.

Keratin is also present in nails and skin. Its role is to strengthen them and give them shine.

What is the role of keratin in the hair life cycle?



First of all, you should know that the life of a hair is punctuated by three phases during which it grows, stagnates and falls.

During the first phase of the hair life cycle, called “anagen”, the keratinocytes (present at the bottom of the hair bulb) will produce a lot of keratin. This secretion will last between 2 and 5 years.

During the next phase, called “catagen”, the secretion of keratin is complete. The hair rooted in the scalp will detach and gradually rise to the surface. This can last between 2 weeks and 1 month.

Finally, during the last “telogen” phase which lasts between 6 and 8 months, the hair is detached from the scalp by the regrowth of the new hair and ends up falling out.

Keratin is therefore synthesized only during the anagen phase. In fact, it is a dead material which does not have the capacity to regenerate; it will be exhausted during the entire life cycle of the hair. It is therefore essential to take care of it in order to preserve it as best as possible.

What is the structure of hair?

Analyzing the structure of the hair allows us to better understand the role of keratin:

The first layer of keratin, called the “cuticle”, protects the hair. It allows the scales of the hair to be joined together to give it a smooth appearance. In addition, the cuticle prevents the water present inside the hair from escaping.

The cuticle acts as protection against external attacks on the hair thanks to a very hard constituent keratin. When this layer is damaged, the scales become detached from each other, or even peel off: the hair then becomes brittle and splits more easily.

The “cortex” is the second layer of the hair. This is the essential part because it is composed of keratinized and pigmented cells which give a solid structure and good elasticity to the hair.

The third and final layer, called “pith”, has no particular impact on the hair.


How to supplement with keratin?

Hair is subjected to external aggressions on a daily basis: coloring and perming, use of heating appliances or harmful chemicals, exposure to UV rays and pollution, or even excessively aggressive brushing. These will considerably damage the outer cuticle of the hair which serves as protection. Knowing that keratin does not renew itself, it is therefore necessary to provide keratin supplementation.

To do this, it is recommended to use cosmetic products and treatments rich in proteins, as well as beauty food supplements enriched with keratin.

The keratin used in cosmetics is called “ hydrolyzed ”, it is different from that used in food supplements which is called “ water-soluble ”.

The keratin food supplement will help to strengthen the hair from the inside (the cortex) and the outside (the cuticle), while cosmetic products and treatments (notably keratin straightening) will only treat the cuticle.

Supplementing with keratin is beneficial for the hair: it brings shine to dull hair, improves the quality and resistance of hair which tends to be damaged, and reduces hair loss , in particular thanks to an improvement in the anagen phases. and telogen.

A supply of keratin also strengthens the structure of the nails, they become harder and less brittle.

The role of diet for keratin synthesis

On the other hand, diet also plays an important role in maintaining strong, resilient and healthy hair.

Indeed, keratin requires, for its transport to the root, a sufficient supply of zinc and vitamin B6. It is therefore advisable to consume foods rich in zinc (oleaginous fruits, seafood, wheat germ, meats, etc.) and vitamin B6 (bananas, poultry, chickpeas, potatoes, etc.).

Discover our food supplement to restore strength to your hair!

Délicure offers vegan, natural and made in France “Hair” gummies enriched with vitamin B6 and zinc. They also contain blueberry, other vitamins (B8, B9, B12 and E) and selenium which preserve the beauty of hair, nails and skin. This set of active ingredients helps stimulate keratin production.

In the form of a cure, these gummies help ensure the maintenance of normal hair, limiting breakage and loss.


Watch our video on the 9 best vitamins for hair:

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