Health, Nutrition, Hygiene and First Aid
This section tests WHO health concepts, nutrient functions and energy values, deficiency diseases, personal and community hygiene, and safe first-aid actions.
Core ideas
- WHO (1948): health is a state of complete physical, mental and social well-being, not merely the absence of disease.
- Macronutrients: carbohydrate 4 kcal/g, protein 4 kcal/g, fat 9 kcal/g. Micronutrients: vitamins and minerals. Water and fibre are essential but not energy-yielding in the usual sense.
- A balanced diet supplies energy and nutrients in correct proportions; BMI = weight in kg ÷ (height in metres)².
- Deficiency examples: protein-energy malnutrition (kwashiorkor, marasmus), beriberi (thiamine B1), scurvy (vitamin C), rickets (vitamin D), iron-deficiency anaemia.
- First aid priorities: check danger, response, airway, breathing, circulation; call emergency help; keep the person safe and warm.
- Sprains and strains: RICE - rest, ice, compression, elevation - in the first 48 hours.
Worked example
A student is 1.75 m tall and weighs 70 kg. BMI = 70 ÷ (1.75 × 1.75) = 70 ÷ 3.0625 = 22.9 kg/m², which falls in the normal range. Reasoning: square the height first, keep units, and interpret against adult Asian/WHO cut-offs rather than guessing.
Traps
Do not give food or drink to an unconscious person. Do not apply heat in the first 48 hours of a sprain. Do not use 9 kcal/g for protein. BMI is a screening tool, not a diagnosis.