Know Thy Hair….
The hair is considered as a tissue which uses the same nutrients of bone, nails and is
formed as bi-product of bone tissue. Hair is made up of the root (or follicle) and the shaft (the visible part of hair)
The Shaft is the visible part of hair which is dead, and consists of 3 layers:
- The cuticle, which consists of colorless, flat overlapping cells. The transparent cuticle gives hair its shiny appearance when it is healthy, and the dull, lifeless look when it is damaged which can happen due to excessive use of heat (straightening irons,etc.) and by chemical damage (colouring etc.). Everyday elements, such as the sun or wind, brushing and harsh handling will also damage the cuticle.
- The cortex, a fibrous layer which contains a pigment (melanin) that defines hair color, hair texture (straight, curly etc), and is responsible for the shaft growth, as well as keratin, a hard fibrous protein which makes up 88% of hair and gives the cortex the properties of elasticity and a high tensile strength.
- Τhe medulla, the ‘’heart’’ of the shaft, consisting of sparse cells and air bubbles. Different amounts of medulla may be present in the hair.
Know Thy Roots…
The root is found within the depths of a pouch like structure called the follicle, buried inside the dermis (outer layer of skin) where hair is generated, and is the widest part of the hair. The hair follicle contains sebum (oil) secreting glands, which make the hair shiny. Stress, illness and lack of proper nutrients will diminish secretion of sebum.
The base of hair root is in the shape of a bulb which is indented with capillaries (tiny blood vessels) and nerve fibers. The cells in the center of bulb regularly divide, and the newly divided hair cells push the previously existing cells up. These cells die slowly as they move upwards, forming the hard hair shaft.