Nutrition & Obesity Revision Sheet

1. 📌 Essentials

• IMC (Body Mass Index): weight (kg) / height² (m² normal: 18.5–24.9.
• BMR: energy needed for vital functions at rest. -TEE:** total energy expenditure = BMR + physical activity.
• Energy conversion: 1 kcal = 4.187 kJ.
• Macronutrient distribution: carbs (~50%), lipids (~30%), proteins (~15%).
• Obesity: excess fat, diagnosed via IMC >30 or >25 + waist circumference.
• Kwashiorkor: protein deficiency causing edema and growth retardation.
• Diet imbalance: excess lipids, insufficient carbs/proteins.
• Main causes of obesity: sedentary lifestyle, poor diet, genetics, psychological factors.
• Surgical treatments: sleeve gastrectomy, gastric bypass, gastric banding.
• Research focus: genetics, inflammation, microbiota, brain-gut axis.

2. 🧩 Key Structures & Components

• Adipose tissue: stores excess lipids, involved in energy balance.
• Hypothalamus: regulates hunger, satiety, and energy expenditure.
• Gastrointestinal tract: signals satiety/hunger via hormones.
• Lipid droplets: intracellular storage form of fats.
• Microbiota: gut bacteria influence energy absorption and metabolism.
• Hormones: leptin, ghrelin, insulin regulate appetite and storage.
• Liver: central in lipid and carbohydrate metabolism.
• Muscle tissue: major site of energy utilization.

---