Physiology and Metabolism

Energy Balance and Metabolic Rate

• An individual's balance of energy expenditure is referred to as their metabolic rate.
• Metabolic rate affects energy balance, which in turn affects body weight.

Regulation of Food Intake

• The hypothalamus plays a crucial role in regulating food intake and energy balance.
• When fat levels decrease below the body's normal range, the hypothalamus slows metabolism to conserve energy.

Growth Hormone Production

• Approximately 50% to 75% of growth hormone production occurs after the onset of deep sleep.
• Growth hormone is essential for growth and development, particularly during childhood and adolescence.

Eating Disorders in Childhood

• Avoidant/restrictive food intake disorders in childhood are characterized by significant weight loss.
• Failure to thrive is more common among children from disadvantaged environments.
• Early onset of feeding disorders is often associated with inadequate care giving.
• Maternal eating disorders are a specific risk factor for an infant's eating or feeding disorder.

Pica

• Pica is a feeding disorder characterized by eating non-nutritive substances, such as insects, wood chips, or dirt.
• Pica is often seen in individuals with intellectual disability.
• Pica among young children (without intellectual disability) often remits when the child experiences increased stimulation.

Failure to Thrive

• Failure to thrive is characterized by growth and eating problems.
• Mothers of infants with failure to thrive are often more insecurely attached than mothers of infants without failure to thrive.
• Failure to thrive may affect physical growth in childhood, but does not affect future cognitive functioning.

Obesity

• Obesity is a chronic medical condition.
• Obesity is usually defined in terms of a body mass index above the 95th percentile.
• Approximately one in six American children are obese.
• Obesity in infancy is strongly related to obesity in later childhood.

Binge Eating Disorder

• Mild binge eating is characterized by one to three episodes of binge eating per week.
• Binge eating disorder (BED) differs from bulimia in that individuals with BED do not have compensatory behaviors.
• BED has become increasingly widespread during this age of abundant fast food and obesity.

Anorexia and Bulimia

• Anorexia is characterized by a refusal to maintain a minimally normal body weight, an intense fear of gaining weight, and a significant disturbance in the individual's perception of their own size.
• Bulimia typically occurs in mid-adolescence to late adolescence.
• Between 50% and 75% of patients with bulimia show full recovery over several years.

Predictors of Recovery and Biochemical Factors

• Higher social class is a predictor of full recovery for individuals with bulimia.
• The neurotransmitter serotonin has been most focused on as a possible cause of eating disorders.
• Biochemical similarities have been found between people with eating disorders and those with obsessive-compulsive disorder.

Risk Factors for Eating Disorders

• Low socioeconomic status has been linked to the development of eating disorders.
• Homosexual men appear to be at greater risk for behavioral symptoms of eating disorders.
• Bulimia, and not anorexia, is mainly a Western phenomenon.

Perpetuating Factors of Eating Disorders

• Starvation symptoms and reaction from others can perpetuate eating disorders.
• A detailed assessment of feeding behavior and parent-child interactions is critical in treating eating disorders in infants and young children.