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CHAPTER EIGHTEEN
Nutrition and Metabolism
she has often ceased to menstruate. She typically has low
self esteem and believes that others, particularly her parents,
are controlling her life. Her weight is something that she can
control. Anorexia can be a one-time, short-term experience
or a lifelong obsession.
Anorexia Nervosa
Anorexia nervosa
(an
o-rek
se-ah ner
vo-sah) is self-imposed
starvation. The condition is reported to affect 1 out of 250
adolescents, most of them female, although the true number
among males is not known and may be higher than has been
thought. The sufferer, typically a well-behaved adolescent girl
from an affl uent family, perceives herself to be overweight
and eats barely enough to survive
(f g. 18.22)
. She is terri-
F ed of gaining weight and usually loses 25% of her origi-
nal body weight. In addition to eating only small amounts
of low-calorie foods, she further loses weight by vomiting,
taking laxatives and diuretics, or exercising intensely. Her
eating behavior is often ritualized. She may meticulously
arrange her meager meal on her plate or consume only a few
foods. She develops low blood pressure, a slowed or irregu-
lar heartbeat, constipation, and constant chilliness. She stops
menstruating as her body fat level plunges. Like any starving
person, the hair becomes brittle and the skin dries out. To
conserve body heat, she may develop soft, pale, F ne body
hair called lanugo, normally seen only on a fetus.
When the person with anorexia reaches an obviously
emaciated state, her parents usually have her hospitalized,
where she is fed intravenously so that she does not starve to
death or die suddenly of heart failure due to an electrolyte
imbalance. She also receives psychotherapy and nutritional
counseling. Despite these efforts, 15% to 21% of people with
anorexia die.
Anorexia nervosa has no known physical cause. One
hypothesis is that the person is rebelling against approaching
womanhood. Indeed, her body is astonishingly childlike, and
FIGURE 18.22
Perceiving herself overweight, this young woman is
tying the measuring tape extraordinarily tight around her waist to have
a waist measurement as small as possible.
FIGURE 18.21
Two types of starvation in the young. (
a
) This child, suF
ering from marasmus, did not have adequate nutrition as an infant.
(
b
) These children suF
er from kwashiorkor. Although they may have received adequate nourishment from breast milk early in life, they became
malnourished when their diet switched to a watery, white extract from cassava that looks like milk but has very little protein. The lack of protein in
the diet causes edema and the ascites that swells their bellies.
(a)
(b)
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