Hair loss
Hair grows in phases, with around one in ten head hairs 'resting' at any given time. The colour, curl, length, thickness and amount of hair depend on genetic factors.
There are many different causes of hair loss, but only those that damage the hair follicles can make the loss permanent. Breaking or damaging the hair shaft has no affect at all on the health of the bulb. The bulb is the only living part of hair and it is anchored to the base of the hair follicle.