Losing hair? You can blame it on the genes. Or, poor diet, lack of sleep, stress, trauma, hormonal changes, illnesses and medication. The list is endless. So, what is this hair loss exactly? The most common hair loss is a natural daily phenomenon, in which re-growth is a given. But this type of hair shedding cannot be classified as a cause of hair loss. Every strand of hair on a human head is genetically programmed to a cycle that includes growth, stabilization, ageing and shedding. On average, a human head sheds about 50 – 125 (depending on gender) but most of them come back after the resting stage as the follicle itself is not destroyed. Trouble begins when the loss exceeds re-growth, or the re-growth is weak and unhealthy. Let’s explore the causes of hair loss plaguing every ‘head’ today.
SOMETHING IN THE “HAIR”
Most people believe they know everything there is to know about hair. After all, how much is there to know? When you pick up a hair from the sink you might give it a quick glance, but no further investigation. There is not much to look at. Is there?
Yes, there is! This little piece of hair is quite complex. A closer look at what a hair is made of and how it grows surprises most people. Hair is a form of “appendage” to the outer layer of skin. It grows from very specialized cells, which produce hair even before we are born. A human head contains between 80,000 and 120,000 hairs. The number of hairs, the type and the colour of each hair is genetically determined. The main purpose of hair is to isolate the tiny blood capillaries, which regulate body temperature.
Each individual hair begins under the skin, in the root of the hair sac, which is called ‘dermal papilla’. The papilla contains cells that take in nutrition and amino acids necessary for the hair to grow. On top of the papilla is the matrix, where hair cells are produced in rather large portions. As these cells are being produced they get pushed upwards. During this process, they “die” and form a very hard substance called keratin. The keratin is formed in long parallel strings within the cells and is kept together with binding compounds called disulphide. As the keratin cells are being pushed upwards, three layers are formed: the medulla, the cortex and the cuticle. The medulla is the core or the central layer. It consists of ball-shaped cells spun with air pockets. The exact purpose of this central core is still not clear.
The next layer, called the cortex, surrounds the medulla. It consists of dead cells filled with keratin. This layer determines the hair type and colour. The outer protecting layer is the cuticle, consisting of around seven overlapping layers of dead cells filled with hard and semitransparent keratin. When the hair reaches the surface of the skin, all cells have run through the process – from living to dead cells – and filled with keratin. As this process goes on, the hair grows longer.