Stress and Eating Disorders

Eating Disorders and Stress

• Anorexia Nervosa (AN):
  • Develops in mid-teens, associated with social media pressures and major stressors/trauma
  • Characterized by a refusal to maintain a minimal body weight, pathological fear of gaining weight, and distorted body image
  • Symptoms: rapid weight loss, excessive concern with body shape and weight, preoccupation with food and calories, decrease in variety of foods eaten, skipping meals, ritualized eating and food preparation, menstrual irregularities/loss of menses, excessive exercise
  • Afflicts mainly adolescent women, with a lifetime prevalence of 0.5%
  • Two types: restricted type and binge-eating/purging type
• Bulimia Nervosa (BN):
  • Characterized by fear of loss of control over eating, excessive concern with body shape and weight, and feelings of shame and secrecy concerning bulimic behaviors
  • Symptoms: consuming large amounts of food at one time, self-induced vomiting, abuse of laxatives, diuretics or diet pills
  • Two types: purging sub-type and nonpurging sub-type
  • Onset: late adolescence or early adulthood, with a lifetime prevalence of 1-3% among women
• Binge Eating Disorder (BED):
  • Characterized by recurrent episodes of binge eating without purging or fasting, feelings of disgust, poor self-esteem, and concerns about weight and body shape
  • Symptoms: bingeing, feelings of lack of control, weight gain, and failed attempts to diet and lose weight
  • Onset: late adolescence or early adulthood, with a prevalence of 1-3%
• Coping Mechanisms:
  • Poor coping skills can lead to a rise in stress, which can result in weight gain or loss
  • Women are more likely to use food to deal with stress, while men tend to use alcohol consumption or smoking
• Stress and Eating Disorders:
  • Stress can lead to HPA axis dysregulation, bingeing, and purging
  • Both BN and healthy women increase food intake of carbohydrates following a stressor
  • Stress has been associated with the onset of BN and BED
• Obesity:
  • Not considered a mental disorder/eating disorder in the DSM
  • Estimated to affect approximately 5 million Americans
  • Rate of obesity among teenagers and adolescents is 17%
  • Risk factors: gender, race or ethnicity, childhood eating and gastrointestinal problems, elevated shape and weight concerns, sexual abuse, and distorted body image### Anorexia Nervosa
• Types of anorexia nervosa:
  • Restricted type: self-starvation without purging
  • Binge-eating/purging type: self-starvation with purging activities
• Characteristics:
  • Fear of gaining weight
  • Distorted body image
  • Refusal to maintain a minimal body weight
  • Pathological fear of gaining weight
  • Weight loss viewed as an important achievement
• Onset: early to middle teens, often following life stressors or dieting
• Lifetime prevalence: 0.5%
• Afflicts mainly adolescent women, with 10 times more females than males affected
• Increasing trend towards early-onset anorexia in girls between 8 and 13 years old

Anorexia Nervosa and Stress

• Dysregulation of the HPA axis
• Difficulty in establishing whether HPA axis abnormalities are related to starvation and weight loss or to anorexia nervosa itself
• Stress leads to hypersecretion of CHR, but this is not directly related to anorexia nervosa

Bulimia Nervosa (BN)

• Symptoms:
  • Fear of loss of control over eating
  • Excessive concern with body shape and weight
  • Feelings of shame and secrecy concerning bulimic behaviors
  • Bingeing and purging
• Important features:
  • Recurrent episodes of binge eating followed by purging or fasting
  • Fear of weight gain and distorted perception of body shape
• Types of bulimia:
  • Purging sub-type BN: self-induced vomiting or misuse of laxatives
  • Nonpurging sub-type BN: excessive fasting or exercise
• Onset: late adolescence or early adulthood, with 90% of cases being female
• Lifetime prevalence: approximately 1-3% among women
• Ten times more females than males are affected
• Perfectionistic type of people who lose control over eating patterns and become ashamed of their binges
• Bingeing often occurs in secret and is triggered by dysphoric or depressed mood, interpersonal stressors, or intense hunger following dietary restraint
• Physical symptoms: permanent loss of dental enamel, menstrual irregularity
• Comorbid disorder: major depression, with 36-63% of bulimia sufferers diagnosed with depression

Bulimia Nervosa and Stress

• HPA axis dysregulation by stress and/or bingeing, which alters cortisol
• Stress causes both HPA axis hyperactivation and bingeing
• Bingeing and vomiting do not influence hormonal secretion
• BN patients do not display a clear association between eating disorder symptomatology and HPA-axis dysfunction
• Study: both BN and healthy women increase food intake of carbohydrates following stress
• Stress has been associated with the onset of BN
• BN patients eat less in general but increase food consumption under stress

Binge Eating Disorder

• Symptoms:
  • Fear of loss of control over eating
  • Bingeing without purging or fasting
  • Feelings of disgust and poor self-esteem
• Characteristics:
  • Onset: late adolescence or early adulthood
  • Prevalence: approximately 1-3%
  • Associated with high levels of depression and impaired social functioning
  • Majority of sufferers are women, but incidence is only 1.5 times higher than in men
• Binge eating ≠ obesity
• Obesity: increased risk for diabetes with central fat distribution

Binge Eating and Stress

• Restrained eaters and emotional eaters overeat in response to stress
• Patients are more emotional eaters
• Moderate heritability (0.5)
• Binge eating serves as an escape from aversive self-awareness or an attempt to elevate mood
• Study: BED women showed greater cortisol response to stress compared to normal subjects
• Obese women show alterations in the HPA axis, probably the effect rather than the cause
• Increased cortisol levels related to central fat distribution, promoting visceral fat accumulation and risk for diabetes