Definition | Clinical Features | Medical Complications | Epidemiology, Course, and Prognosis | Etiology and Pathogenesis | Treatment
In contrast to anorexia nervosa and bulimia nervosa, obesity is
classified not as a psychiatric disorder but as a medical disorder.
Obesity is an excessive accumulation of body fat and operationally
is defined as overweight. The BMI, defined as weight (kg)/height
(m2), has the highest correlation, 0.8,
with body fat measured by other, more precise laboratory methods. Mild
overweight is defined as a BMI of 25–30 or
body weight between the upper limit of normal and 20% above
that limit on standard height–weight charts. Obesity is defined
as a BMI greater than 30 or body weight greater than 20% above
the upper limit for height (Bray 1978; see Figure 23–1).