Excessive or abnormal hair loss is known as alopecia, and there are several kinds. What all hair loss has in common, whether it's in men or women, is a symptom of something that's gone wrong in your body. Your hair will remain on your head where it belongs unless hormone imbalance, disease, or some other condition occurs. That condition may be as simple as having a gene that makes you susceptible to male or female pattern baldness or one of the forms of alopecia areata, or it may be as complex as a whole host of diseases.
Fortunately, hair loss can be a symptom of a short-term event such as stress, pregnancy, disease, or medication, which can all alter hair's growth and shedding phases. In these situations, hair will grow back when the event has passed. Once the cause of the loss is addressed, hairs go back to their random pattern of growth and shedding, and your problem stops.
The first two types of hair loss in women are associated with dihydrotestosterone (DHT), a derivative of the male hormone, testosterone.
Androgenetic Alopecia
The majority of women with androgenetic - also called androgenic - alopecia have diffuse thinning on all areas of the scalp. (Men rarely have diffuse thinning but instead have more distinct patterns of baldness.) Some women have a combination of two pattern types.
Androgenic alopecia in women is due to the action of androgens, male hormones that are typically present in only small amounts. Androgenic alopecia can be caused by a variety of factors tied to the actions of hormones, including some ovarian cysts, taking high androgen index birth control pills, pregnancy, and menopause.
Just as in men, the hormone DHT appears to be at least partially to blame for the miniaturization of hair follicles in women suffering with female pattern baldness. Heredity plays a major factor in the disease.
Telogen Effluvium
When your body goes through something traumatic like child birth, malnutrition, a severe infection, major surgery, or extreme stress, it can impact your hair. Many of the 90% or so of hairs in the growing (anagen) or transitional (catagen) phases can actually shift all at once into the resting (telogen) phase.
About six weeks to three months after the stressful event, the shedding phenomenon called telogen effluvium may begin. It is possible to lose handfuls of hair at a time when in full-blown telogen effluvium.
For most who suffer with this, complete remission is probable as long as severely stressful events can be avoided. For some women, however, telogen effluvium is a mysterious chronic disorder and can persist for months or even years without any true understanding of the triggering factors or stressors.
Anagen Effluvium
Anagen effluvium occurs after any insult to the hair follicle that impairs its cellular-level mitotic or metabolic activity. This hair loss is commonly associated with chemotherapy. Since chemotherapy targets rapidly dividing cancer cells, your body's other rapidly dividing cells -- such as hair follicles in the growing (anagen) phase -- are also greatly affected. Soon after chemotherapy begins, approximately 90% or more of hairs in the anagen phase can fall out.
The characteristic finding in anagen effluvium is the tapered fracture of the hair shafts. The hair shaft narrows as a result of damage to the matrix. Eventually, the shaft fractures at the site of narrowing and causes the loss of hair.
Alopecia Areata
An inappropriate inflammatory reaction is behind alopecia areata. A person's own immune system attacks the roots of hair follicles. Symptoms include patchy shedding of hair, which sometimes develops quite suddenly. About 70% of patients recover their hair within two years, whether or not they receive treatment.
Traction Alopecia
This condition is caused by localized trauma to the hair follicles from tight hairstyles that pull at the hair over time. If the condition is detected early enough, the hair will regrow. Braiding, cornrows, tight ponytails, and extensions are the most common styling causes of traction alopecia. Learn more about the different types of alopecia.
Published on March 1, 2010