Are you like almost 99% of the people in the world that just know that a brown or black or red or white hair keeps growing from time to time without fully understanding the hair structure? Well, I think it’s high time for you to at least know something…even if it’s little…about the dead keratinous extension on your head.
So, this article will educate you on the important points you can easily keep at the back of your mind, helping you to provide the much needed day-to-day hair care for a wonderful, fabulous, and shiny hair.
Some Quick Points About Your Hair Structure
- Melanin pigments determine the color of the hair as much as the skin. The different chemical composition of melanin determines the hair color like the Eumelanin determines the brown or black hair color. The Pheomelanin adds a red color to the hair, and loss of pigment or lack of it can make the hair to turn white or gray.
- The hair is made up of dead keratin called “Hard Keratin” which is different from the keratin of the skin.
- Each hair strand is called hair shaft. And each hair shaft grows from the hair root, which is located down in the dermis. Each hair shaft grows through an elongated tube-like structure called the Hair follicle.
- We have approximately 5 million hair follicles in the human body, with close to 100,000 follicles on the human scalp. The areas where there are no follicles are the palms, the sole, nipples, umbilicus, joints of the finger, genital area, the red part of the lips.
- Connected to the hair follicle is the sebaceous gland, which secretes sebum that prevents water loss from the skin and scalp inclusive
- Attached to the hair follicle is the arrector pili muscle, and when this muscle contract, the hair shaft will stand at attention.
- The hair follicle is being nourished by the blood vessels deep down the dermis. The lower end of the follicle is called the papilla (or the dermal or follicular papilla).
- There are three types of hair. We have the Vellus hair, which rarely exceeds 2 cm. And the Terminal Hair, which is longer, coarser, thicker, and more pigmented than the Vellus hair.
Before adolescence, the terminal hair is only available on the eye lashes, scalp, and the eye brows. And after adolescence, the terminal hair replaces the Vellus hair. We also have hairs that fall in between the Vellus hair and the Terminal hair. They are called Intermediate Hairs.
Formation of the Hair – How Your Hair Grows
Deep below the epidermis…in the dermis at the bottom of the hair follicle….lie the unique cells that produce the hair. These cells have enormous replicating abilities, constantly dividing. As more cells appear, the older cells get pushed vertically upward, causing them to degenerate.
Since the cells die as they move through the hair follicle, the upper part of the hair is made up of dead cells (keratinous cells) that are joined together by an intercellular cement-like substance. That is, each hair strand is composed of many dead keratinous cells that are joined together by the cement-like substance.
The only living thing in the hair formation resides in the dermis – the cells that constantly divide and find their way up to the skin through the tube-like hair follicle.
The action of these cells depends on hereditary factors and the diet your diet. As long as the cells are healthy and normal, the hair continues to grow.