Though hair growth patterns are different among women and men, most of the hair growth fundamentals are the same. Keratin is the resilient protein that makes up hair strands. The strand is anchored to the skin by the hair follicle which contains the hair bulb. This bulb is the place where hair cells divide and grow to create the hair shaft. It is in the hair bulb that blood vessels nourish cells and deliver hormones that modify growth and structure at different times of the hair’s life.
There are about 110,000 hair follicles in the scalp with the average loss of hair around 50 to 100 scalp strands a day. Hair has two main phases of growth: anagen phase and telogen phase. The anagen phase lasts anywhere from two to six years, and this is when hair is actively growing. The telogen phase is the cessation of growing, the hair is resting to be eventually shed and replaced with a new hair. Ninety percent of the time, hair is in the anagen phase with the resulting ten percent of time in the resting, telogenic phase. Normal hair grows about a half an inch a month.
Now everyone is familiar with male-pattern baldness. It’s when a guy’s hair growth seems to be forming a horseshoe about the fellow’s head. Well, female-pattern hair loss seems to have a strong genetic component, and it starts with a visible thinning of the hair at the crown of the head. This is because of the miniaturization of the hairs as their growth cycle is disrupted. These wispy hairs never reach their full potential of size and girth. This thinning then spreads backward and sideward until the back of the head is affected. A widening part line or smaller ponytails are signs of thinning hair.