Obesity

The Pathophysiology of Obesity

  • Presented by: Dr. Márta Balaskó

  • Affiliation: Institute for Translational Medicine

Evolution of Obesity

  • Time Frame: 2000 BC to 2000 AD

  • Focus: The changes in the understanding and prevalence of obesity over time.

Energy Balance Factors

  • Components:

    • Metabolic Rate (MR)

    • Feeding State

    • Nutritional State

    • Body Weight

Prevalence of Overweight Population in the EU (2019)

  • Statistics by Age Group (BMI ≥ 25.0):

    • 18-24 years: Low

    • 25-34 years: Moderate

    • 35-44 years: High

    • 44-54 years: Very high

    • 55-64 years and older: Significantly increased prevalence.

Body Mass Index (BMI)

  • Calculation:

    • BMI = Body Weight (kg) / Height (m)²

  • Classification:

    • Normal: 18.5 - 24.9

    • Overweight: 25 - 29.9

    • Obesity:

      • Class 1: 30 - 34.9

      • Class 2: 35 - 39.9

      • Class 3 (Morbidly Obese): >40

Definition of Obesity

  • Definition: Increase in BMI due to fat accumulation.

  • Key Measurements:

    • Major factors affecting BMI and obesity classifications.

  • Statistics:

    • USA (2016): 40% adult obesity prevalence, 18.5% childhood obesity.

    • Central-Eastern Europe: 40-50% prevalence.

Body Composition and Energy Stores

  • Healthy Young Adult Components:

    • Adipose Tissue: ~15 kg (130-140,000 kcal)

    • Protein: ~10-12 kg (35-40,000 kcal)

    • Carbohydrates: ~0.3 kg (1,100 kcal)

    • Water: ~42 kg

    • Minerals: ~4 kg

Measurement Techniques for Body Fat

  • Methods:

    • BMI and skinfold thickness measurements

    • Body weight measurements underwater or using air displacement plethysmography

    • Dual energy X-ray absorptiometry (DEXA)

    • Bioelectrical impedance analysis

    • Magnetic resonance imaging (MRI) and computed tomography (CT)

Global Obesity Problem

  • Statistics:

    • Various regions classified within obesity prevalence percentages.

Obesity Trends in the U.S. (1991-2003)

  • Graphs and Statistics show increase in obesity prevalence amongst adults by year.

Obesity Etiology

  • Genetic Factors: (50-70% contribution to obesity)

    • Family traits observed in adopted children, patterns in identical twins.

    • Influences from specific gene mutations (ob/ob, db/db mice).

    • Taste preferences and inherited features affecting food intake regulation.

Neurohormonal Regulation of Food Intake

  • Key Components:

    • Increasing evidence of hypothalamic regulation through hormones.

    • Role of leptin, ghrelin, and insulin in regulating hunger and satiety.

Metabolic Syndrome associated with Obesity

  • Components:

    • Visceral obesity, insulin resistance, type 2 diabetes, dyslipidemia, and hypertension.

Eating Disorders Related to Obesity

  • Types:

    • Anorexia nervosa - characterized by low BMI and avoidance of food intake.

    • Bulimia nervosa - binge eating followed by purging.

    • Consequences of both disorders including hormonal disturbances and high mortality rates.

Treatment of Obesity

  • Focus Areas:

    • Diet: Reducing caloric intake by 20%, including types like low-carb, high-fiber diets.

    • Behavioral Therapy: Strategies to modify dietary habits and enhance mental health support.

    • Drugs: Explore medications' efficacy, safety, and long-term complications.

    • Surgical Options: Discuss types of bariatric surgery and effectiveness.

    • Lifestyle Changes: Emphasis on exercise, NEAT, and general wellness.

Consequences of Obesity

  • Physical Health Risks: Cardiovascular issues, joint problems, increased risk of various diseases (e.g., type 2 diabetes, cancers).

  • Psychosocial Impact: Stigmatization, mental health issues, and societal discrimination.