Obesity is probably the most common chronic disease in our country. As much
as 33% of the population is over-weight, with the percentage higher among
women and minorities. Obesity results from an imbalance between energy
intake and energy expenditure. Genetic, environmental, and behavioral
factors (poor appetite control, unhealthy eating habits, lack of exercise)
all influence the balance between energy intake and output. When intake
exceeds output over the long term, the excess energy is stored as fat. Excess body fat, particularly when distributed on the upper body, increases
the risk of hypertension, coronary artery disease, non-insulin-dependent
diabetes mellitus, gallbladder disease, sleep apnea, gout, and certain types
of cancer (e.g., prostate cancer). Although obesity is a chronic disease
with adverse health consequences, in our society it carries such a stigma
that many people -- including health professionals -- don't believe that the
obese person deserves any sympathy at all, let alone medical treatment for
the condition.

Four Common Misconceptions About Obesity
David S. Weigle (University of Washington School of Medicine, Seattle)
describes four common misconceptions about obesity:
First, that body weight is not a physiologically regulated variable but is
set by acquired food habits and conscious or unconscious desires.
Second, that an individual can set his or her body weight to any desired
level without adverse effects on health.
Third, everyone who weighs more than the numbers set forth in certain life
insurance tables is at increased risk of mortality.
Fourth, that body fat distribution is not an important health consideration.
Despite the trumpeting of the popular press, obesity is not a disorder of
body weight regulation. Obese people regulate their weight appropriately,
but regulation is around an elevated set point. Body weight is usually
highly stable after adolescence, increasing slowly (by a half a pound per
year) over the lifetime. "This degree of weight stability implies a precise
match between energy intake and expenditure over a prolonged period," says
Weigle. Even a slight excess in daily energy intake, such as the calorie
content of a single soda cracker, would result in a 2-pound weight gain a
year. "This precision in balancing daily energy intake and energy
expenditure would be difficult to achieve on a purely volitional basis.