Hair loss or hair thinning is most commonly associated with predetermined genetic factors and the overall aging process. More serious hair loss than just thinning can be due to another cause, but finding that cause may be quite difficult if the scalp is unscarred and appears normal. It is true that life’s challenges may cause thinning of hair or complete hair loss. These challenges include emotional trauma, illness, protein deprivation, and hormonal changes such as those experienced in pregnancy, puberty and menopause.
Several health conditions, including thyroid disease, anemia, protein deficiency, and low vitamin levels can cause hair loss. Alopecia areata is a form of hair loss produced by the autoimmune destruction of hair follicles in localized areas of the skin. Ask your physician to rule out treatable causes of hair loss by testing your thyroid and other blood tests, such as a CBC (complete blood count).
Most drugs do not cause hair loss, even though ‘hair loss’ may be listed as a drug side effect. The exception to this is cancer chemotherapy and immunosuppressive medications, which commonly cause hair loss. Hair usually regrows after six to twelve months.
It may be helpful to understand the life cycle of your own hair, which covers most of your body, except for the palms of our hands and the soles of our feet. Hair is made of a protein called keratin that is produced in hair follicles in the outer layer of skin. Usually about 90% of the hair on a person’s scalp is growing. Each follicle has its own life cycle that can be affected by age, genetics, disease and a wide variety of factors. The life cycle is divided into three phases:
- Anagen is defined as active hair growth that lasts between two to six years
- Catagen is defined as transitional hair growth that lasts two to three weeks
- Telogen is defined as a resting phase that lasts about two to three months; at the end of this resting phase, the hair is shed, new hair replaces it and the growing cycle starts again.
The rate of hair growth slows down as people age. More hair follicles stay in the resting phase, and the remaining hairs become shorter and fewer in number. In contrast, male pattern baldness may occur as early as the teens, characterized by gradual hair loss and disappearing hair from the crown and the front part of the scalp. This is a genetic condition called Androgenic alopecia.
Scarring alopecias result in permanent hair loss. This may be caused by inflammatory skin conditions (cellulitis, folliculitis, acne), and other skin disorders (such as some forms of lupus and lichen planus) often result in scars that destroy hair’s ability to regenerate. Hair too tightly woven and pulled can also result in permanent hair loss, as can hot combs.
Telogen effluvium is hair thinning that is temporary over the scalp that occurs because of changes in the growth cycle of hair. Many more hairs than usual enter the resting phase at the same time, causing hair shedding and subsequent thinning.
Trichotillomania, seen most frequently in children, is a psychological disorder in which a person pulls out one’s own hair.
Alopecia universalis causes all body hair to fall out, including the eyebrows, eyelashes, and pubic hair.
Treatments are few and far between for the aforementioned conditions. Some people may benefit from using Rogaine (minoxidil), which appears to provide modest hair regrowth on areas of the scalp that have gone bald. Many users report good results. Another drug on the market for hair loss is Propecia (finasteride) for male pattern baldness. There are other drugs and treatments that you may want to explore with your dermatologist, including hair transplantation. Corticosteroids may have only temporary relief. If your hair loss is as serious as the conditions listed, it is important to see your dermatologist and rule out causes that may be temporary or fixable.