Changes in physiology with increasing fat mass.

Obesity has reached epidemic proportions in the USA with a nearly fourfold rise in the prevalence of childhood obesity. There are many possible etiologies of obesity as the adipose tissue plays a significant, complex role in the physiology of fuel metabolism and hormone regulation. The development of obesity represents a pathophysiologic increase in fat mass in which multiple metabolic pathways are deranged. The consequences of these metabolic derangements, including insulin resistance and inflammation, are reflected in obesity-related comorbidities and can be seen in the setting of pediatric obesity. Obese adolescents demonstrate increased rates of early maturation, orthopedic growth abnormalities, diabetes mellitus, obstructive sleep apnea, hypertension, steatosis, and polycystic ovarian syndrome, placing this group of children at risk for long-term health problems and reduced quality of life. Given the negative short- and long-term impact of obesity on children, careful attention should be paid to the unique health issues of this "at-risk" population with both prevention and early intervention strategies.