is a natural symptom of the aging process.
However, gray hair can appear at any
age. The graying process begins as early
as high school or college for some people,
whereas others do not undergo the process
until they are 60 years old. Gray hair
is more noticeable in people who have
darker hair because of the contrast
in color, but people with naturally
lighter hair are just as likely to undergo
the graying process.
Causes and Risk
Each hair contains two
parts: a shaft (the top part) and a
root (the base part under the scalp).
The root grows out of a follicle that
has cells filled with a pigment known
as melanin. This pigment defines the
distinct color of hair (black, brown,
blonde, red, or anything in between).
The graying of hair begins when the
body ceases to produce melanin. The
melanin level in the hair follicle decreases
as age increases, and this decline results
in a more transparent color, like gray,
silver, or white, as the hair grows.
Aging is an irreversible process, so
the melanin pigments are not likely
to be produced in the same quantities
that they were produced in earlier.
Eventually, the hair will become completely
In addition to the natural aging process,
there are certain medical conditions
that may be associated with graying
of hair. Thyroid disorders, vitiligo,
vitamin B12 deficiency, and anemia are
linked with graying hair. Additionally,
a medical condition known as alopecia
areata causes the non-gray hair to fall
out overnight, leaving only the white
hairs. This condition leaves the impression
that an individual’s hair turned
Gender and genetics
may also contribute to the graying of
hair. Graying is typically observed
in men around the age of 30 years old,
whereas the onset of graying hair in
women is typically observed around the
age of 35 years old. Hereditary factors
are also significant. An individual
will typically begin the graying process
around the same age of which his or
her parents began graying.
have indicated that there is a correlation
between graying of hair and smoking,
side effects of certain medications
such as antidepressants and drugs for
treating cancer, and arthritis.