Our hair grows in cycles, and at any given time, a small percentage of our hair
follicles are at a point in the growth cycle where the hair is shed in preparation for new
hair to begin growing. Normal individuals lose some hair every single day. While
previous estimates on what constitutes 'normal' hair loss have been quoted as high as
100 to 150 hairs a day, recent studies show that number to actually be closer to 35 to
40 hairs a day. This means that you will see evidence of some shedding of hairs as
part of your normal grooming routine.
Yet what concerns us here isn't the normal shedding of the hair, but rather
abnormal hair loss, also known as alopecia [al-oh-PEE-shah]. Alopecia is commonly
found in three forms: androgenic alopecia [an-druh-JEN-ik al-oh-PEE-shah], alopecia
areata [al-oh-PEE-shah air-ee-AH-tah], and postpartum alopecia. Each of these types
of alopecia is characterized as follows:
Androgenic alopecia, also called Androgenetic [an-druh-je-NET-ik] alopecia, is
the most common form of alopecia and is the result of genetics, aging, and hormonal
changes that combine to cause changes in the hair follicle. These changes result in
the miniaturization of the terminal hair into vellus hair. The condition can found in
individuals from their teens and upward in age. It is frequently seen by the age of
By the age of thirty-five, some forty percent of both men and women show some
degree of hair loss. With men, androgenic alopecia is often evidenced by the thinning
of the hair in the front and at the crown of the head, progressing to the traditional
horseshoe shaped fringe of hair around the sides of the head. When it occurs in men,
androgenic alopecia is referred to as 'male-pattern baldness' and the condition affects
approximately forty million men in America alone.
In women, androgenic alopecia progresses as a generalized thinning of the hair
all over the crown and top areas of the head. Among American women, some twenty
million cases of androgenic alopecia are reported.
Alopecia areata is a skin disorder wherein the body's autoimmune system
suddenly begins to attack the hair follicles. The hair loss from alopecia areata is
typically seen in patches on the head and or body, and can progress to the complete
loss of hair from the head (called alopecia totalis) and can even spread to result in
loss of all hair on the head and body (called alopecia universalis). Alopecia areata can
occur in both men and women of any race, and any age, although it usually begins in
childhood. In men, about ten percent of the cases of alopecia areata result in loss of
facial hair (called alopecia barbae).
Alopecia areata is a fairly common disease affecting about 1.7 percent of the
world's population, with over 4.7 million cases reported in the United States. Its
progression is often sporadic and can seem capricious. Patches of hair can be lost in
one location, and then re-grow normally, and be lost again. It might also seem as
though the patches "move" over time, as an area of lost hair can re-grow while new
patches of loss form on other places. Other people may find that their alopecia areata
begins as a small spot of hair loss, and suddenly spreads, with or without re-growth
in previously affected areas. Still others find that their alopecia only ever affects a
single, small area.
Although alopecia is a common disease, it is not widely known, and even though
it is not life-threatening, its sporadic nature and tendency toward recurrence often has
profound psychological effects on the sufferer. It can impact the person's life and ability
to function at school, work, and in social settings.