Hair loss can be due to a number of conditions and it is not just the head that hair can be lost from. Certain skin injuries can prevent the regrowth of hair in patches around the area of damage.
Hair follicles can be found all over the body and not just on the head. Hair loss on the head can be caused by scarring of the scalp. This will shrink the hair follicles preventing them from producing new hair shafts.
Scarring can sometimes be caused by the sun. Fine hair or blonde hair is more susceptible to burning from the sun and when this happens it will damage the hair follicles causing permanent damage. There are many adverts regarding the skin and sunburn, the scalp is also skin and the same precautions should be taken.
Injuries to the skin such as burns will damage the layers of skin which may never fully regrow. The hair follicles receive the same treatment, the damage will stop the hair follicles from reproducing hair and unfortunately there will be permanent damage. A good example of this damage can be seen on Practitioner Simon's personal diary thread
Bacterial or fungal skin infections can also cause the hair to stop growing. Damage to skin through infection will have an adverse effect on the hair follicles. Dead skin can grow again but if the infection has caused the hair follicles to shrink there may be permanent damage in that area.
Cancer medication such as chemotherapy is known to cause hair loss to the head as well as the body. The hair follicles on the head shrink and can no longer hold the hair roots. This is normally a temporary state and after the medication is stopped hair will begin to grow again. Unfortunately the skin on the body that was affected may not.
There has been much research over recent years into how hair grows, what the causes of hair loss are and how it can be treated. Corticosteroid injections have been successful in treating alopecia areata but as with all medications what is successful for one person is not for another. Loss of hair completely from the body (known as alopecia universalis) is rare and the underlying cause has to be found. There is not always a cure and hair regrowth will not happen.
Skin injuries are frequent from small scratches to large areas where an accident was involved. Skin ages over the years and becomes thinner as we get older. This has an effect on the hair follicles which also shrink. Adversely some medication can cause the hair follicles to produce more hair and so there is a thickening of hair around the body. When medication is completed this excess hair will fall out.
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