Eating Disorder and Obesity

Eating Disorder and Obesity 

• Eating Disorders: Involve persistent disturbances in eating behavior that impair health and daily functioning.

• Common disorders: Anorexia nervosa, Bulimia nervosa, Binge-eating disorder.

Obesity: Not classified as a psychiatric disorder in the DSM but is rising at alarming rates and contributes to significant morbidity and mortality.

Connection: Disordered eating patterns often coexist with obesity.

Anorexia Nervousa

Definition: Not simply a “lack of appetite” but a relentless pursuit of thinness leading to a significantly low body weight.

DSM-5 Criteria:

• A: Restriction of energy intake resulting in significantly low body weight.

• B: Intense fear of gaining weight or becoming fat.

• C: Disturbance in body weight/shape perception.

Subtypes:

• Restricting Type: Extreme limitation of food intake.

• Binge-Eating/Purging Type: In addition to restriction, includes bingeing and/or purging behaviors.

Bulimia Nervousa 

Definition: Characterized by recurrent binge eating followed by inappropriate compensatory behaviors.

DSM-5 Criteria Highlights:

• Recurrent episodes of binge eating (eating an unusually large amount of food in a short time with a loss of control).

• Inappropriate compensatory behaviors (self-induced vomiting, misuse of laxatives, fasting, or excessive exercise).

• Occurs at least once a week over 3 months.

Clinical Notes:

• Typically, individuals are within a normal weight range or slightly overweight.

• Often accompanied by feelings of shame and guilt.

Comparing Eating Disorder

Anorexia Nervosa:

• Weight: Markedly low.

  1. Atypical anorexia: despite extreme weight loss, bmi remains in the “normal” range

• Behavior: Restrictive intake (or binge/purge in one subtype).

• Body Image: Distorted perception; intense fear of weight gain.

Bulimia Nervosa:

• Weight: Normal or slightly overweight.

• Behavior: Binge eating with compensatory behaviors.

• Body Image: Overconcern with weight; feelings of shame.

Binge-Eating Disorder:

• Weight: Often overweight or obese.

• Behavior: Binge eating without compensatory measures.

• Body Image: Concerns present, though less rigid dietary restraint compared to other disorders.

Risk Factor and Demographics 

Age of Onset:

• Most eating disorders begin in adolescence.

• Binge-eating disorder often develops between ages 30–50.

Gender Differences:

• Historically seen as predominantly affecting females; current ratio is about 3:1 (female:male).

• Men’s body dissatisfaction may focus on muscularity.

High-Risk Groups:

• Individuals in professions emphasizing thinness (e.g., models, ballet dancers).

• Athletes in sports with weight restrictions.

• Sociocultural pressures and media influence play significant roles.

Medical Complication of Eating Disorders

Anorexia Nervosa:

• Heart arrhythmias and risk of cardiac arrest.

• Electrolyte imbalances leading to kidney damage.

• Osteoporosis due to low bone density.

• Other signs: dry skin, brittle hair, lanugo (fine hair growth).

Bulimia Nervosa:

• Dental erosion and mouth ulcers from repeated vomiting.

• Swollen salivary glands (“chipmunk cheeks”).

• Electrolyte disturbances impacting heart and muscle function.

General Issues:

• Chronic malnutrition may lead to organ damage and increased risk for self-injury or suicide.

Course and Outcomes 

Anorexia Nervosa:

• Mortality rate is high; complications (e.g., heart arrhythmias, suicide) are common.

• Recovery is possible even after prolonged illness.

• Long-term studies indicate about 51–63% eventual recovery.

Bulimia Nervosa:

• Prognosis is generally good with approximately 70% of patients achieving remission.

• Some continue to struggle with bingeing, shape concerns, and substance-abuse issues.

Binge-Eating Disorder:

• High rates of clinical remission after intensive treatment.

Note: Early detection and treatment are critical for improved outcomes.

Association with Other Psychopathology

High Rates of Comorbidity:

• Depression: ~68% in anorexia nervosa, 63% in bulimia nervosa, nearly 50% in binge-eating disorder.

• Obsessive-Compulsive Disorders: Common in anorexia and bulimia nervosa.

• Personality Disorders: Approximately 58% of women with eating disorders may have a personality disorder.

• Substance Abuse: Frequently co-occurs in binge-eating/purging subtypes.

Risk and Causal Factors: An Overview

Multifactorial Etiology:

• Biological Factors: Genetic predisposition, brain structure and neurotransmitter imbalances.

• Sociocultural Influences: Western media, internalization of the thin ideal, family influences.

• Individual Variables: Personality traits (e.g., perfectionism), negative emotionality, dieting behaviors.

Conceptual Model:

• Best understood via the diathesis–stress model where genetic factors heighten sensitivity to environmental pressures.

Biological Factors in Eating Disorders

Genetics:

• Family and twin studies indicate high heritability for anorexia and bulimia nervosa.

• Recent GWAS found a genetic locus on chromosome 12 linked to anorexia nervosa and metabolic factors.

Brain and Neurotransmitters:

• Hypothalamus Role:

  • Lateral hypothalamus stimulation promotes appetite.

• Serotonin:

  • Abnormalities (such as altered 5-HIAA levels) suggest disrupted serotonergic function.

Set Points & Reward Sensitivity:

• The body’s “set point” resists significant weight changes.

• Differences in reward processing (e.g., response to food cues) may predispose to binge eating or restrictive behaviors.

Sociocultural Factors Influencing Eating Disorders

Media and Cultural Ideals:

• Exposure to Western media (TV, magazines) is linked to body dissatisfaction.

• Studies (e.g., in Fiji) show that media can shift local attitudes toward thinness.

• Icons like Twiggy and Kate Moss have influenced the “thin ideal.”

Internalization of the Thin Ideal:

• Believing that thinness equals beauty and success increases risk.

• Social comparisons and peer evaluation reinforce these beliefs.

Family Influences:

• Families of patients often exhibit rigid attitudes, high expectations, and focus on dieting.

• Parental preoccupation with appearance may contribute to the development of eating disorders.

Individual Risk Factors and Psychological Influences

Personality Traits:

• Perfectionism: An enduring trait linked to rigid dieting and excessive self-criticism.

  • More pronounced in women; men with eating disorders tend to be less perfectionist.

Body Dissatisfaction:

• A powerful predictor of eating disorder onset.

• Distorted self-perceptions lead to chronic dieting and negative self-evaluation.

Dieting and Negative Emotionality:

• Dieting is common and can trigger or worsen disordered eating.

• Negative moods and depression are predictive of binge eating and dietary restriction.

Treatment of Eating Disorders – Anorexia Nervosa

Medical Stabilization & Refeeding:

• Hospitalization and measures like intravenous feeding to restore weight.

• Aggressive refeeding protocols may be successful short term, yet without addressing psychological issues, gains are often temporary.

Medications:

• Antidepressants have limited evidence.

• Olanzapine (an antipsychotic) may benefit by addressing distorted beliefs and promoting weight gain.

Treatment of Anorexia Nervosa – Family Therapy & CBT

Family Therapy:

• Maudsley Model is the treatment of choice for adolescents.

• Involves 10–20 sessions over 6–12 months with phases:

  • Refeeding and re-establishing healthy eating habits.

  • Negotiating new patterns of family relationships.

  • Termination with focus on long-term support.

Cognitive-Behavioral Therapy (CBT):

• Aims to modify dysfunctional beliefs about food, weight, and self.

• Often used for both anorexia and bulimia, though success in anorexia may be limited due to cognitive rigidity.

Treatment of Bulimia Nervosa

Cognitive-Behavioral Therapy (CBT):

• Leading treatment; focuses on normalizing eating patterns and challenging dichotomous food beliefs.

• Controlled studies show elimination of binge–purge cycles in 30–50% of cases.

Medications:

• Antidepressants (with a positive response often seen within the first 3 weeks) reduce binge frequency and improve mood.

Interpersonal Psychotherapy (IPT):

• An alternative focusing on improving interpersonal functioning.

Treatment of Binge-Eating Disorder (BED)

Pharmacological Options:

• Use of antidepressants, appetite suppressants, and anticonvulsants (especially given high comorbidity with depression).

Psychotherapeutic Approaches:

• Randomized trials comparing IPT, guided self-help CBT, and behavioral weight loss:

  • At 6 months, remission rates were similar.

  • At 2-year follow-up, IPT and guided CBT outperformed behavioral weight loss.

Emerging & Transdiagnostic Treatments

• Enhanced Cognitive-Behavior Therapy (CBT-E):

  • A transdiagnostic approach targeting eating pathology regardless of specific diagnosis.

  • Two forms:

    • Default (focused): Targets disordered eating, extreme dieting, purging, and binge eating.

    • Broad: Also addresses perfectionism, low self-esteem, and relationship issues.

  • Studies show higher remission rates compared with IPT, with benefits maintained at follow-up.

• New Options for Adults with Anorexia Nervosa:

  • Multiple approaches (CBT, psychodynamic, treatment as usual) yield similar clinical benefits.

  • No single superior treatment yet—patient preferences and clinician expertise are key.

Defining Obesity & Its Medical Impact

Definition Using BMI:

• Underweight: BMI < 18.5

• Normal: BMI 18.5–24.9

• Overweight: BMI 25.0–29.9

• Obese: BMI ≥ 30; Morbid obesity: BMI ≥ 40 or >100 lbs over ideal weight.

Medical Issues:

• Increased risk for heart disease, hypertension, diabetes, and certain cancers.

• Obesity is linked with a reduction in life expectancy by 5–20 years.

Prevalence:

• In the U.S., approximately 36% of adults are obese and 34% are overweight.

• Significant state-by-state and demographic variations exist.

Weight Stigma & Sociocultural Influences on Obesity

Weight Stigma:

• Obese individuals often face harsh judgment and discrimination.

• Bias exists even among health care professionals, affecting treatment quality.

Media & Cultural Portrayals:

• Negative stereotypes in media perpetuate biased perceptions.

• Weight-based discrimination can affect legal outcomes and social interactions.

Risk and Causal Factors in Obesity – Genetics & Hormones

Genetic Influences:

• BMI is polygenic; GWAS studies have identified many genetic regions (e.g., 97 regions related to BMI and fat distribution).

• Specific genetic mutations (found in a subset) are linked to binge eating.

Hormonal Regulation:

• Leptin: Produced by fat cells; signals fat reserves to the brain. Obesity often involves leptin resistance.

• Ghrelin: Produced by the stomach; stimulates appetite. Elevated in conditions like Prader–Willi syndrome

Environmental & Family Influences, & Pathways to Obesity

Environmental Factors:

• Easy access to hyperpalatable foods engineered with high fat and sugar.

• Large portion sizes and aggressive food marketing contribute to overeating.

• Time pressures and convenience drive choices toward fast food and prepackaged meals.

Family Influences:

• Early overfeeding and family eating habits may predispose to more adipose cells.

• Family behaviors around food and emotional support can have long-term impacts.

Social Contagion:

• Close social ties may influence weight gain; obesity can be “socially contagious.”

Stress & Comfort Food:

• Chronic stress and negative emotional states can trigger consumption of high-calorie comfort foods.

Summary & Key Takeaways

Eating Disorder Treatments:

• Emphasis on medical stabilization, refeeding, and addressing psychological issues.

• Family therapy and CBT remain central for anorexia and bulimia.

• Emerging transdiagnostic approaches (CBT-E) show promise across disorders.

Obesity Overview:

• Defined by BMI, obesity is a major global health issue with significant medical and social impacts.

• Multifactorial causes include genetic predisposition, hormonal regulation, environmental factors, and sociocultural influences.

Integrated Perspective:

• Both eating disorders and obesity require comprehensive, individualized treatment strategies.

Overview of Obesity Treatment Challenges

Modest Weight Loss:

• Typical sustained weight loss of ~7 pounds is common.

• Even small reductions can yield health benefits.

Treatment Complexity:

• Biological defenses (set-point, hormonal changes) make weight loss difficult.

Prevention is Key:

• Preventing weight gain may be easier than achieving and maintaining weight loss.

Metabolic & Hormonal Challenges in Weight Loss

Set-Point Theory:

• The body defends a specific weight range through hormonal and metabolic adaptations.

Physiological Responses to Weight Loss:

• Increased hunger, slower metabolic rate, and reduced satiety.

• Energy expenditure decreases with weight loss, making maintenance challenging.

Implication:

• Relapse rates are high due to these built-in biological defenses.

Strategies & Simple Behavioral Changes

Individual Strategies:

• Reduce daily caloric intake by 100 calories (e.g., three fewer bites per meal).

• Increase physical activity (e.g., taking the stairs, walking an extra mile).

• Improve sleep quality (adults sleeping 7–8 hours tend to maintain healthier weights).

Key Message:

• Small, consistent changes can help prevent and reduce gradual weight gain over time.

Public Policy Approaches to Obesity Prevention

Calorie Labeling:

• NYC’s mandate for chain restaurants to post calorie information reduced average calorie consumption by 14%.

Regulatory Actions:

• Attempts to ban large sugary drinks (though legal challenges may arise).

• Implementation of the Healthy, Hunger-Free Kids Act to improve school food standards.

Additional Measures:

• Better regulation of food advertising to children.

• Subsidizing healthier foods and increasing taxes on sugar-sweetened beverages (e.g., a 20% tax could lead to nearly 4 pounds weight loss per year).