At its simplest, overweight is caused by taking in
more calories than the body uses. This difference is called the ‘‘energy gap.’’ A 2006 study done by the
Harvard School of Public Health and published in
the journal Pediatrics found that, on average, American
children consumed between 110 and 165 extra
calories than they use up every day. Over a 10-year
period, these extra calories would add 10 lbs to their
weight. However, already overweight teens took in an
average of 700–1,000 extra calories every day, resulting
in an average of 58 extra pounds.
Causes
There are many reasons why the energy gap exists,
these reasons are related to both increased food intake
and decreased energy use. Food intake reasons
include:
-increased consumption of sugary beverages, and
along with this, a decreased consumption of milk
-tendency to super-size portions. In some fast food
restaurants portions have almost tripled since the
1970s.
-more meals eaten away from home
-more use of prepared foods in the home
-increased snacking between meals along with fewer
meals eaten together as a family
-heavy advertising of high-sugar, high-fat foods to
children
-decrease in children carrying their lunch to school
from home
-poor eating habits such as skipping breakfast and
later snacking on high fat, sugary foods
Inadequate energy use reasons include:
-more time spent watching television or using the
computer.
-fewer physical education requirements at school.
According to the Centers for Disease Control, in
2000, only 8% of elementary schools, 6.4% of middle
schools, and 5.8% of high school required daily
physical education classes.
-fewer children walking to school. In 1969 half of all
school childrenwalked or biked to school. The ratewas
87% for children living within 1mile of their school. In
2003, only 15% of children walked or biked to school.
-decreased recess in grades 1–5. More than 28% of
schools do not provide a regularly scheduled recess in
these grades.
-fear of crime, which limits outdoor activities of children
-more affluence. Teen access to cars has increased
over the past 30 years.
Other factors that affect childhood obesity include
an inherited tendency toward weight gain, mental illness,
binge eating disorder, and eating in response to
stress, boredom, and loneliness, poor sleeping habits,
and having at least one obese parent.
In rare cases, medical or genetic disorders can
cause obesity. For example, Prader-Willi syndrome
is a genetic disorder that causes an uncontrollable
urge to eat. The only way to prevent a person with
Prader-Willi disorder from constant eating is to keep
them in an environment where they have no free
access to food. Other genetic and hormonal disorders
(e.g. hypothyroidism) can cause obesity. Certain
medications also can cause weight gain (e.g. cortisone,
tri-cyclic antidepressants), but these situations
are the exception. Most children are too heavy
because they eat to much and/or exercise too little.
Symptoms
The most obvious symptom of obesity is an accumulation
of body fat. Other symptoms involve
changes in body chemistry. Some of these changes
cause disease in children, while others put the child at
risk for developing health problems later in life. Children
who are overweight are at increased risk of:
-type 2 diabetes. This disease is appearing in children
and young adults at an alarmingly high rate. In the
past, it was usually seen in older adults.
-high blood pressure (hypertension)
-fat accumulation in the liver (fatty liver/liver disease)
-sleep apnea
-early puberty; early start of menstruation in girls
-eating disorders
-joint pain
-depression
-increased anxiety and stress
-low self-worth
-exposure to social prejudice and discrimination
Diagnosis is usually made on the basis of the
child’s BMI. To better assess the problem, the physician
will take a family history and a medical history
and do a complete physical examination, including
standard blood and urine tests. A thyroid hormone
test may be done to rule out hypothyroidism as the
cause of obesity. Based on the physician’s findings,
other tests may be performed to rule medical causes
of obesity.
