ETIOLOGY
Obesity is a complex condition involving genetic, hormonal, metabolic and environmental factors.13
Conditions such as hypothyroidism, hypercortisolism and hyperpituitarism are rare causes of
overweight among youth, and are associated with growth retardation rather than the accelerated rate of
biological development seen in exogenous obesity.13 Adolescent overweight and decreased insulin
sensitivity have recently been associated with intrauterine malnutrition during fetal hypothalamic
appetite center and sympathetic nervous system development.13 The interaction of genetically
determined body size and fatness with an environment of low energy expenditure and caloric excess is
the primary cause of adolescent overweight.