About Hair Loss
First of all, losing hair is normal! Our follicles go through cycles of growth (“anagen”) lasting from 2 to 7 years before shutting down for a brief transitional phase (“catagen”) and a 3-month resting phase (”telogen”). It is then that a hair is shed and a new cycle begins, providing replacement hairs for those that have been lost. It is normal to lose about 50-150 hairs a day; at any given time, about 85%-90% of our hair is in the growth phase, and 10%-15% is in the resting phase. It is only when this normal growth cycle becomes disrupted by genetic and hormonal influences, severe stress or illness, abnormal conditions of the scalp, drugs, hair styling techniques, compulsive hair-pulling (trichotillomania), etc. that there is a net loss of hair that actually becomes noticeable in the mirror. Because the process is insidious and the eye is easily fooled, hair loss may escape notice until 50% is already gone from a given area.
A word about “alopecia”
This is simply the general term for any kind of hair loss. It says nothing about its cause. If your doctor has told you that you have “alopecia,” ask if he or she could be more specific.
The common causes of hair loss
Fortunately, the most common types of hair loss respond well to transplantation; however, there are many conditions that can result in the loss of hair, and not all of them are amenable to surgery. Before you spend thousands of dollars, it is critically important for a hair loss expert to determine if your particular type of hair loss is “transplantable” or not.
- Androgenetic alopecia (AGA): A hereditary predisposition to developing progressive hair loss in one of several distinctive patterns is by far the major cause of hair loss in both men and women. AGA is caused by the effects of the hormone dihydrotestosterone, or DHT on follicles that are genetically programmed to be sensitive to DHT. DHT, an “androgen,” is derived from testosterone, another androgen, through the action of a specific enzyme in the scalp. Men and women who manage to keep their hair throughout their lives do not have DHT-sensitive follicles. For unknown reasons, only the hair follicles in certain areas of the scalp on men with male pattern baldness or women with female pattern hair loss are sensitive to DHT, hence the term “pattern” hair loss. Even in the vast majority of balding men (and some women with thinning hair), the follicles around the back and sides of the head are resistant to the effects of DHT and continue growing for a lifetime; it is this phenomenon that provides the basis for hair transplantation.At least half of all men will experience some type of hair loss by age 50 and a quarter of men will lose some hair by the age of 25. What may come as a surprise to most people is that the numbers are almost the same for women. Noticeable hair loss, generally in the form of thinning, affects more than 50% of all women during their lifetime. But although a woman’s hairline also may recede as she ages, common female “pattern” hair loss is different from male pattern baldness. While many women experience thinning of hair over the entire head—including the area from which follicles would normally be obtained for a hair transplant—it is exceedingly rare for a woman to “go bald.” The factors involved in female hair loss are more complex than those in male hair loss; hence, hair loss in women must be treated differently from hair loss in men. Androgenetic alopecia in men (“male pattern baldness”) is often ideally suited to hair transplantation. Unfortunately, for many reasons, far fewer women—generally about 15%-20% of those women seeking treatment for thinning hair—are suitable candidates for surgery. (African American women with isolated “traction alopecia” are a notable exception; see below, “African American hair loss.”)
- Genetics and aging: If there is a history of hair loss in your biological relatives, there is an increased likelihood that you will also lose hair. As alluded to above, the incidence of hair loss also increases with age.
- Telogen effluvium (TE): This is generally considered to be the 2nd most common cause of hair loss. Affecting greater numbers of women than men, TE can be acute (lasting less than 6 months) or chronic (more than 6 months duration). The condition is due to a shift in the percentage of follicles in the anagen (growth) phase to the telogen (resting) phase. In telogen effluvium, as much as 30%-40% (up from the normal 10%-15%) of the follicles may enter the telogen phase and result in massive shedding of hair; thus, instead of the normal 100 hairs shed on a daily basis, the number may increase to 300 or 400.TE can be triggered by many things, including severe physical or emotional trauma, surgery, the post-partum state, certain drugs, high fever or severe illness, depression, and crash diets/bulimia/protein deficiency with marked weight loss. There is usually a lag time of 2-4 months between the triggering event and the beginning of shedding. Fortunately, most TE is self-limiting, with a return to normal shedding after about 6 months; however, in the relatively rare cases of chronic TE, the shedding can continue indefinitely. A hair transplant is never the solution to telogen effluvium!
- Additional hormonal (endocrine) influences other than testosterone/DHT: Hormonal factors can be particularly significant for women. During pregnancy, the hormonal state results in thick, lush hair; however, as many women have experienced first hand, in the post-partum period there is generally marked shedding and thinning (telogen effluvium) of the abundance of hair they had during pregnancy. Fortunately, this is usually temporary and reversible after 6-12 months. Menopause, polycystic ovary syndrome (PCOS), ovarian tumors, and thyroid disease all can alter the normal hormonal balance and result in hair loss.
- Anemia (iron deficiency): According to the World Health Organization, iron deficiency is the most common and widespread nutritional disorder in the world. Fortunately, it is easily reversible, along with any hair loss it may have caused. Hair loss due to low iron levels results in generalized thinning rather than loss in a specific pattern.
- Hypothyroidism (low thyroid levels): This is another easily reversible cause of hair loss. Like iron deficiency anemia, hypothyroidism causes diffuse thinning of the hair on the scalp. Hyperthyroidism may also cause hair loss, but this is much less common.
- Autoimmune diseases: The best-known example of an autoimmune condition resulting in hair loss is alopecia areata (one or more patchy areas on the scalp), as well as the related alopecia totalis (total loss of all scalp hair), and alopecia universalis (loss of all body hair). This type of alopecia almost always resolves on its own and is only rarely treated with hair transplantation. Other autoimmune diseases that can cause hair loss include lupus and Hashimoto disease (Hashimoto’s thyroiditis).
- Scarring (“cicatricial”) alopecia: There are a number of fairly uncommon and poorly understood inflammatory conditions of the scalp that result in the complete destruction of hair follicles and, therefore, permanent hair loss. This type of hair loss characteristically occurs in a patchy distribution, as opposed to the much more common male or female “pattern” type of hair loss, or the diffuse thinning experienced by many women. A type of scarring alopecia known as frontal fibrosing alopecia seems to be occurring with increasing frequency. FFA typically affects post-menopausal Caucasian women, resulting in a receding hairline that can mimic that of a man. There is also loss of eyebrow hair in about 75% of these women. Only rarely do scarring alopecias respond well to hair transplantation, with the exception of central centrifugal cicatricial alopecia, or CCCA. (See “African American hair loss” below.)
- Trichotillomania (hair-pulling disorder): This is a poorly understood condition involving the uncontrollable urge to pull hair from the scalp, most commonly, but also from the eyebrows, eyelashes, pubic area, or anywhere on the body. The hair pulling can either be conscious, done in an effort to relieve the irresistible compulsion to pull, or absent-mindedly, without even being aware that it is happening. Many afflicted individuals play with the pulled hair, rub it over their face, or even bite, chew, and eat. (Large amounts of swallowed hair can lead to an intestinal obstruction requiring emergency surgery.) The condition usually begins in the pre-pubertal years, and can either be outgrown, in which case the patchy areas of hair loss may regrow, or continue for many years until most of the hair on the head is permanently gone. Women constitute 90% of those suffering from trichotillomania; as would be expected, they experience considerable emotional distress, with feelings of anxiety, depression, shame, embarrassment, humiliation, and self-loathing. Treatment of the disorder is challenging; hair transplantation may be an option only in very carefully selected cases where the hair pulling has ceased for at least a year and the affected area(s) can be adequately addressed with the available remaining donor hair.
- Drugs: As mentioned above, telogen effluvium can be caused by a host of medication prescribed for everything from acne and birth control to high blood pressure and Parkinson’s disease. (Very few drugs other than those used for cancer chemotherapy cause anagen effluvium, or loss of hair that is still in the growing phase of the hair growth cycle. Interestingly, though the hair lost as a result of chemotherapy almost always grows back, the color and texture are often different.)
- Radiation treatment: Unfortunately, unlike with chemotherapy, hair loss caused by radiation therapy is usually permanent due to the permanent damage caused to the scalp and follicles. Some cases of radiation alopecia can be treated with hair transplantation; as always, the decision to recommend surgical hair restoration is one that needs to be made by an experienced hair transplant surgeon.
- African American hair loss: There are some special considerations with regard to the cause and treatment of hair loss in African American patients that calls for experience and good judgment on the part of the physician formulating a plan of action.In addition to the genetic (hereditary) type of hair loss commonly seen in both men and women of all races, the various styling methods often used by African Americans can also cause hair loss. A very common condition seen after years of tight braiding and weaves is “traction alopecia,” where the follicles literally die as a result of constantly being pulled; the hair usually will not grow back once it is gone. Traction alopecia typically involves the hairline, sometimes all the way down to the sideburns and behind the ears, resulting in varying degrees of thinning or “recession.” Fortunately, hair transplantation is an option for many African American men and women (or anyone else) with traction alopecia, and excellent, permanent results can be achieved with a very high level of satisfaction.
Central Centrifugal (spreading outward from the center) Cicatricial (scarring) Alopecia, or CCCA is a poorly understood type of “scarring alopecia,” or inflammatory condition of the scalp. It occurs almost exclusively in women of African descent and can be either primary (of unknown etiology) or secondary (resulting from chemical burns from perms/relaxers). Lye-based relaxers can burn the scalp so severely that the underlying follicles are permanently damaged and no longer capable of growing hairs. The scar tissue that destroys the follicles is beneath the surface of the skin; thus, though CCCA can result in large areas of complete balding, the scarring itself is usually not visible to the eye. CCCA is not hereditary. Women with CCCA have very fragile hair that is susceptible to breakage, and need to take special care to handle their hair gently. The results of hair transplantation in CCCA are usually very disappointing, though there are occasional success stories.