Hair Loss Forms and Causes

Hair loss can have several different types and forms and its causes can differ accordingly. The most commonly known form of hair loss is male pattern baldness with its typical horseshoe balding pattern. This type of baldness is hereditary. Female form of hereditary hair loss, known as female pattern baldness, has the same cause as male pattern baldness - dihydrotestosterone effects on susceptible hair follicles which cause their miniaturization - but its form is diffuse so that women lose their hair around their entire scalp. Another form of baldness it the so-called patchy or spot baldness which is typical for alopecia areata. The patches can be of the size of a small coin but they can spread to the larger area and in severe cases alopecia areata can lead to the loss of all hair on the scalp and face (alopecia totalis) and even on the entire body (alopecia universalis). Alopecia areata is thought to be an autoimmune disease when the body’s defense system identifies some hair follicles as a health threat and decides to attack and destroy them. Some also believe that alopecia areata is genetically determined but no concrete proof of its heredity exists.

The difference between the male and female form of hereditary hair loss lies in the way their hair follicles react to the dihydrotestosterone attacks. This reaction is unrelated to the dihydrotestosterone levels in the body. You might have heard some “experts” say that people who produce more testosterone (which is being converted into dihydrotestosterone) are more likely to lose hair. This, however, is not true as only follicles in some people are susceptible to the dihydrotestosterone attacks and women produce less testosterone than men but about 25% of them lose their hair due to this hormonally active metabolite. In men hair follicles susceptible to the dihydrotestosterone effects lie mainly in the frontal scalp area and on top of their head and these follicles typically lose all their hairs (one follicle may produce between one and four hairs) whereas the follicles on the sides and in the back of their head are typically resistant to the miniaturization caused by dihydrotestosterone. In women almost any follicle around their scalp can be sensitive to the dihydrotestosterone attacks but their hair follicles seldom lose all their hair. This gives women their typical diffuse balding pattern.