What is Hair?

Hair is more than just a pretty accessory; it tells us about our genetics, health, and even emotions. From the tale of Rapunzel to Samson’s mystical strength, it seems like our hair speaks volumes about ourselves. And that’s true — whether you have thick, dark locks or luscious blond strands. It also plays an important role in protecting our skin and keeping us warm from the elements. It can even shield us from harmful UV rays, as well as protect our eyes and ears from dust and other particles. And, of course, it adds to our overall appearance and boosts confidence.

But what exactly is it? Scientifically, it’s a filamentous biomaterial composed of proteins in particular the protein keratin. It has a medulla near the center of the structure and is surrounded by the cortex, which contains the major part of the fiber mass, and cuticle, a layer of dead cells with overlapping flat surfaces (Fig. 1). The structures of these layers are studied in detail by light, electron and atomic force microscopy as well as X-ray diffraction.

The medulla is loosely packed and disordered, and the cortex has a relatively rigid structure. The keratin coils organize into intermediate filaments that bundle together to form macro-fibrils. These macro-fibrils are surrounded by the cuticle, which is made of flat and square-shaped cuticle cells that are tightly adhered to the cortex cells proximally. In addition, they have extensive overlapping at the periphery. The overlapping surface areas help to form an insulating barrier that prevents moisture, dust and chemicals from entering the hair structure.

Each individual hair grows from a follicle in the dermis of the skin. At the base of each follicle is an area called the papilla, which contains an artery that supplies blood to the root. The follicle is lined with oil glands that secrete sebum. The sebum lubricates the follicle and provides nutrients to the growing hair.

Hairs are pushed upward through the follicle by a tiny muscle called arrector pili. Then, they become coated in a layer of oil from the sebaceous glands that helps to protect the hair from water and other elements. This coating, which makes the hair shiny, is also responsible for keeping it soft and supple. The hair also contains pigment cells that give it its color, which is determined by the amount of melanin produced in those cells. The resulting granules are distributed evenly throughout the hair and help to keep it resistant to damage. For this reason, it’s important to maintain good hygiene habits and not over-process your hair. Over-processing can cause it to become brittle and dry. It’s also a good idea to wear a hat when you go outside and limit the times that you use heat-based styling tools. And, of course, eat a diet full of fruits and vegetables that are rich in vitamins A and C. These vitamins help to support collagen production, which in turn leads to stronger strands.