In general, a cuticle It is a lining that appears in many animals covering various parts of their body, in some cases even the entire body, for example, the exoskeleton of insects is a cuticle.
A cuticle is characterized by being a material Lasted, flexible and composition non-mineralunlike bone material which is also a hard tissue but it is not flexible and its composition is mineral.
In humans it appears cuticle in the nail and in the hair from any part of the body.
Next we will study the structure and composition of the hair cuticle, what its function is and how its condition affects the appearance and health of the hair.
Structure of hair and hair cuticle
Each hairAs a physiological structure, it is made up of two well-differentiated parts: the hair follicle and the hair fiber.
- hair follicle: is the living part of the hair. It is formed by a tubular invagination of the skin where stem cells are concentrated.
- hair fiber: It is formed by dead keratinized cell structures and protrudes from the skin forming hair and body hair.
The hair fiber, in turn, can be divided into two parts. The rootwhich is inserted into the follicle, and the hairy stem. It is here, on the hair shaft, where we find the cuticle.
The hair cuticle is the outermost layer of hair shaft. It is hard and transparent. The dead keratinized cells form overlapping scales into each other, similar to the arrangement of tiles on a roof.
A normal hair cuticle can have between 5 and 7 layers deep and is strongly linked to the bark or cortex, the middle layer of the hair fiber. The marrow It is the central zone, the most internal.
The shape of the cuticle cells can vary. They can be elongated, oval or flat. Others may have sharp or tapered ends.
With this variety of shapes, maximum coverage of the internal parts of the hair is achieved, ensuring maximum protection against external agents, as we will see below in the functions of the cuticle.
Functions of the cuticle in the hair
Thanks to keratinization, the cuticle represents the first line of protection of the hair in front of external agents. The cuticle is also responsible for part of the mechanical resistance of the hair and controls the hair fiber hydration.
For its part, the bark or cortex It is formed by elongated keratinized cells united in a compact way between them, being the main responsible for the shape, resistance and elasticity of the hair. Here also appear the pigments that give color to the hair.
More internally is the marrow, formed by rounded keratinized horn cells with a disorganized and loose arrangement. The medulla is present only in the thickest hairs and, having a large amount of air, behaves like thermal insulation.
How to maintain a healthy cuticle?
The cuticle can be damaged by the action of external agentslike the sun or the wind. But the greatest damage is usually caused by excessive mechanical handling, such as brushedapplication of high temperatures Y aggressive chemicals.
For example, dyes, relaxers or perms They seek to alter the shape or color of the hair, and for this they have to penetrate to the cortex, below the cuticle. These are very aggressive processes for the cuticle.
Damage to the hair cuticle leads to a loss of protection for the hair shaft, making it more fragile. On an aesthetic level, the alteration of the cuticle also causes loss of brightness and one dull appearance.
To maintain a cuticle in optimal condition, it is best to avoid all these treatments. Treatments can also be used conditioners Y capillary sunscreen.