In non-scarring alopecia there is no actual destruction of follicles or scar tissue formation. This means that the follicles are still present, although they may be diseased, altered in some way, or their growth arrested. The alopecia in the non-scarring conditions shows up as an increased shedding of hair leading to gradual loss of hair density and fullness. The hair loss may be all over the scalp, in other words diffuse, or it may be in discrete patches or localised mainly over the crown. Recognising various patterns gives the dermatologist clues as to what type it is and what is causing it. The scalp skin can look pretty normal and the openings of the hair follicles can be seen as tiny pores even in the areas which are quite bald.
There are dozens of causes of non-scarring alopecia. Some are associated with general medical problems including infections, auto-immune diseases like lupus erythematosus, thyroid disease, and severe kidney disease. In many of these cases the hair loss is just a minor symptom in relation to the other problem.
A large number of medications may cause non-scarring hair loss as a side effect in a small percentage of people. The best known example are the drugs used in chemotherapy for cancer. In these cases the hair loss may begin within days of starting treatment and can be quite dramatic, sometimes leading to complete baldness. Once the drug or drugs are stopped the hair follicles will recover and the hair will regrow. With many other drugs the hair loss is not noticed for several weeks or months after the medication is started. This often makes it quite difficult for the dermatologist to pinpoint the problem accurately, particularly when a patient is taking several different types of prescribed medications!
Some nutritional deficiencies can also cause non-scarring hair loss. Severe protein lack due to malnutrition is one— fortunately rare in our society. Zinc deficiency has also been associated with hair loss and can occur in some rare illnesses in which zinc in food is not absorbed properly from the intestinal tract.
One of the more common nutritional deficiences is iron deficiency. Some women become iron deficient because of (multiple pregnancies (and inadequate iron supplementation) tar because of heavy periods, or by being completely vegetar-jian and thus missing out on iron-rich food. Our hair seems |to need iron to grow properly and if our iron stores are low the hair may start to thin out a little. If there are other hair loss problems going on at the same time, for example andro-genetic alopecia these may be exaggerated by the iron deficiency. This can be easily rectified by taking iron supplements but it must be supervised—a person can take too much!