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Metabolic

Obesity

Excessive body fat accumulation affecting health and metabolism

Overview

Obesity is a complex, chronic, multifactorial disease characterised by excessive body fat that impairs health. It is not simply a result of willpower or lifestyle choices — genetics, hormones, gut microbiome, sleep, stress, and the environment all play roles. Obesity significantly increases the risk of type 2 diabetes, cardiovascular disease, certain cancers, joint disease, and mental health conditions.

BMI Classification (Asian populations may use lower thresholds):

  • Underweight: <18.5
  • Normal weight: 18.5–24.9
  • Overweight: 25–29.9
  • Obesity Class I: 30–34.9  |  Class II: 35–39.9  |  Class III: ≥40

Waist circumference is equally important: >90 cm in men and >80 cm in women (Asian) indicates high metabolic risk.

Contributing Factors

  • Excess calorie intake from ultra-processed foods
  • Physical inactivity and sedentary lifestyle
  • Genetic predisposition
  • Hormonal conditions — hypothyroidism, PCOS, Cushing's syndrome
  • Medications — steroids, some antidepressants, antipsychotics
  • Poor sleep and chronic stress
  • Social determinants — food environment, income, education

Health Consequences

  • Type 2 diabetes and insulin resistance
  • Heart disease, stroke, hypertension
  • Obstructive sleep apnoea
  • Cancers — colon, breast, endometrial, kidney
  • Non-alcoholic fatty liver disease (NAFLD)
  • Osteoarthritis — especially knees and hips
  • GERD and gallstones
  • Depression and anxiety
  • Infertility

Treatment — A Stepped Approach

1. Dietary Changes:

  • Caloric deficit of 500–750 kcal/day for 0.5–1 kg/week loss
  • Reduce ultra-processed foods, sugar, and refined carbohydrates
  • Increase vegetables, fruit, lean protein, and whole grains
  • Portion control and mindful eating

2. Physical Activity:

  • 150–300 minutes/week of moderate aerobic activity
  • Add resistance training to preserve muscle mass
  • Reduce prolonged sitting — take breaks every 30 minutes

3. Behavioural Support:

Structured weight management programmes, psychological support, and self-monitoring (food diary, step counting) significantly improve outcomes.

4. Medical Treatment:

  • GLP-1 receptor agonists (semaglutide, liraglutide) — significant weight loss
  • Orlistat — reduces fat absorption

5. Bariatric Surgery (BMI ≥40, or ≥35 with comorbidities):

Sleeve gastrectomy or gastric bypass produce the greatest and most sustained weight loss and often resolve diabetes and hypertension.

A Compassionate Approach Matters

Obesity is a medical condition, not a character flaw. Even a 5–10% reduction in body weight produces significant health benefits. Speak to your family doctor for a non-judgmental, personalised weight management plan.

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