Science Form 2 Chapter 2

2. BALANCED DIET
• What is diet?
• Diet refers to all the food we eat each day.
• Balanced diet
• The food that contains the right amounts of the seven classes to
meet the daily requirements of the body.
• It is depends on some factors such as age, body size, sex,
occupation, physical activity, climate and state of health.

3. IMBALANCED DIET
• Result in :
I. Malnutrition
II. Deficiency disease

4. ENERGY VALUE OF FOOD
• The amount of energy released from one gram
of a particular type of food. a.k.a. calorific value
• Unit : calories (cal) or joules (J)
• 1 cal = 4.2 J
• Example :
Class of Food Energy values (kJ g-1)
Carbohydrates 17
Proteins 18
Fats 39