Balanced Diet and Calorific Value

2.1  Balanced Diet and Calorific Value

1. Health problems caused by malnutrition

  • Goitre
  • Marasmus
  • Scurvy
  • Kwashiorkor
  • Rickets

2. Calorific value of food: the amount of energy that is released from the complete oxidation or combustion of 1 g of that food

3. Unit of calorific value 

  Calorific value   

 \(\text {1 calorie (cal)} \)         \(\text {= 4.2 joules (J)}\)

\(\text {1 kilocalorie (kcal) = 4 200 joules (J)}\)

                               \(\text {= 4.2 kilojoules (kJ)}\)

4. Calorific values of carbohydrate, fat and protein
Class of food Carbohydrate Fat Protein
Calorific value (\(\text {kJ } \text{g}^{-1}\)) 16.7 37.6 16.7
5. Effects of consuming total calories that do not meet individual requirement
Health problem Cause Effect
Obesity Consuming food with high calorific value excessively over long periods of time
  • Diabetes mellitus
  • Arteriosclerosis
  • High blood pressure
Anorexia nervosa Individual's refusal to eat due to worries of gaining weight
  • Malnutrition
Atherosclerosis Cholesterol deposition on the artery walls
  • High blood pressure
  • Heart diseases
  • Stroke
Diabetes mellitus Consuming food and drinks high in sugar over long periods of time
  • Affects vision, kidney and the various system
  • Slow recovery of wounds
High blood pressure Consuming food with high salt content over long periods of time
  • Risk of heart diseases
  • Stroke
6. Eating patterns and effects on their health
Eating patterns Effects of health
Excessive sugar
  • Obesity
  • Tooth decay
  • Diabetes mellitus
Absence of beneficial nutrients
  • Malnutrition
Artificial colouring and sweeteners
  • Cancer
  • Infertility
  • Diabetes mellitus
  • Damage to liver and kidneys
Excessive salt
  • High blood pressure
  • Heart diseases
  • Damage to kidneys
Caffeine in carbonated drinks
  • Insomnia 
  • Anxiety
  • Addiction