Hair Growth and the Hair Cycle
The normal human scalp contains 100,000 to 150,000 follicles that produce thick terminal hair. Humans normally lose about 100 hairs per day. When hair enters its resting phase, growth stops and the bulb detaches from the papilla. The old hair is pushed out as the new shaft starts to grow. When an old hair is shed, a small, white swelling is found at the bottom of the hair shaft. Most people assume that this is the growth centre of the hair, but it is just the club, detached lower end of the hair shaft. The dermal papillae and the growth centre of the hair remain in the scalp. Scalp hair grows at a rate of about 1 to 1.5 cm per month.
How Many Causes of Hair Loss
1. Alopecia
Hair loss leading to baldness is called Alopecia. Most people lose hair because they have inherited a genetic design that predisposes them for baldness. Hair loss can also be caused by underlying medical problems, drugs, infections and a variety of other factors. Medical problems that can cause diffuse hair loss include Stress, prolonged disease, anaemia, thyroid disease, connective tissue diseases (such as Lupus), severe nutritional deficiencies; mainly iron, calcium and vitamins deficiencies, crash dieting, surgical procedures, and severe emotional problems.
2. Androgenic Alopecia
