What are the contributing risk factors for obesity?

Contributing Risk Factors for Obesity

Obesity is a chronic, relapsing, multifactorial disease influenced by genetics, biological factors, environmental conditions, and socioeconomic circumstances that promote positive energy balance through increased food intake and decreased energy expenditure. 1

Genetic and Biological Factors

• Genetic variants: Most obesity has polygenic risk factors with several variants strongly associated with BMI 1

  • Single gene variant obesity is rare
  • Family history of obesity significantly increases risk 1

• Hormonal and neurological factors:

  • Dysregulation of the gut-brain axis leading to increased hunger and decreased satiety 1
  • Hormonal imbalances involving leptin and ghrelin 1
  • Secondary endocrine disorders 2:
    • Hypothyroidism
    • Cushing's syndrome
    • Growth hormone deficiency
    • Hypogonadism
    • Pseudohypoparathyroidism type Ia

Environmental and Socioeconomic Factors

• "Obesogenic environments" 1:

  • Greater availability of fast-food restaurants
  • Poor neighborhood walkability
  • Perceived safety risks limiting physical activity
  • Limited access to healthy food options

• Socioeconomic factors:

  • Low socioeconomic status 1
  • Food insecurity 1
  • Chronic stress, particularly in racial and ethnic minority populations 1
  • Unemployment and social disadvantages 3

Behavioral and Lifestyle Factors

• Dietary habits:

  • High caloric intake 1
  • High dietary fat consumption 1
  • Consumption patterns influenced by cultural factors 4

• Physical activity:

  • Sedentary lifestyle 1
  • Physical inactivity 1
  • Limitations to physical activity 1

• Sleep patterns:

  • Insufficient sleep 1
  • Sleep disorders 1

Psychological Factors

• Mental health conditions:
  • Bidirectional association between depression and obesity 1
  • Anxiety 1
  • Stress 1
  • Eating disorders 1

Medication-Related Factors

• Medications associated with weight gain 1, 2:
  • Certain antipsychotics
  • Some antidepressants
  • Glucocorticoids
  • Some antiepileptic drugs
  • Insulin and insulin secretagogues

Special Considerations

• Age and gender factors:

  • Higher prevalence among women 5
  • Increasing prevalence with age 5
  • Postmenopausal status in women 1

• Urban development and modernization:

  • Changes in lifestyle habits associated with urbanization 4
  • Reduced physical demands in modern occupations 3

Clinical Implications

• Obesity significantly increases risk for numerous comorbidities:

  • Type 2 diabetes (93-fold increased risk in women with BMI >35) 6
  • Cardiovascular disease (86% increased risk with 20% weight gain in males) 6
  • Hypertension 1
  • Dyslipidemia 1
  • Sleep apnea 1
  • Certain cancers 1, 6
  • Osteoarthritis 1

• Comprehensive assessment should identify:

  • Contributing factors to weight gain 1
  • Barriers to treatment 1
  • Presence of obesity-related complications 1
  • Impact of excess weight on physical and mental health 1

Understanding these multifaceted risk factors is essential for developing effective prevention and treatment strategies that address the complex nature of obesity.