The hair is attached to the base of the follicle by the hair root, which is where the hair actually grows and is nourished by small blood vessels.
The thickness of the hair depends on the size of the hair follicle from which it grows. As we age, the hair follicle shrinks and the hair becomes finer.
It is helpful to understand the normal hair cycle, which, in turn may help us understand why hair loss occurs.

The hair growth cycle is usually described as having 3 phases.

• Anagen – The growth phase
• Catagen – The degradation phase
• Telogen – The resting phase

The life of the average hair is 4 years; this period of growth is the Anagen phase.
Then there is a short Catagen phase, 2-4 weeks, where the hair is degraded.
The Telogen or resting phase is of approximately 3months in duration and then the cycle is repeated.

Most people shed around 100 hairs every day, this is normal and nothing to be alarmed about, as the average scalp has around 100,000 hair follicles. Not more than 10% of the follicles are in the resting phase at any time.

When the resting phase is extended and the growing phase is shortened, and miniaturization of the hair follicle occurs, this inevitably leads to hair loss.