NUTRITION

Objectives:

1. To understand why organisms require food
2. To list the constituents of an ideal diet
3. To know the functions of each component of an ideal diet
4. To state the role of water in living organism
5. To know that food has an energy value
6. To know that different people have different demands for energy

PROTEINS

• Complex organic substance containing
C, H, O, N, S and P

• Made up of amino acids of which there are 20 naturally occurring types.

• Amino acids combine in various ways to form millions of different proteins, just like how 26 letters of the alphabet form words. 

FUNCTIONS

• Essential for the synthesis of protoplasm, for growth and repair of worn out cells

• Synthesis of enzymes and hormones

• Formation of antibodies to combat diseases

• Source of energy (17KJ/g)

Deficiency in VITAMINS

VITAMIN A 1.0mg
Function: is necessary for normal eyesight, body tissues, growth and bone formation, and resistance to infection

Signs of Deficiency: Poor night vision or night blindness, loss of appetite, increased susceptibility to
infection, and changes in the skin and teeth

Sources : carrot, dark-green leafy vegetables, eggs

VITAMIN E 15.0mg
Functions:
- an antioxidant- protects fats and vitamin A in the body from destruction by destructive oxygen fragments.
- stabilizes cell membranes and protects tissues that are found throughout the body.

Sources: Vegetable oils such as soyabean oil, corn oil

Signs of Deficiency: Anemia in infants and nerve damage in adults.

VITAMIN K 120μg
Function -to regulate blood clotting

Sources: Sunlight, fortified milk and margarine, eggs and butter, produced by the micro-flauna found in the large intestine

Signs of Deficiency: Excessive bleeding and an inability for blood to clot

VITAMIN C
Functions:
-Needed for formation of intercellular substances
-Maintenance of healthy epithelial tissues
-promotes the healing of wounds, bone fractures, bruises, hemorrhages and bleeding gums

Sources : Fresh citrus foods, green vegetables

Signs of Deficiency: black-and-blue marks, bleeding gums, nose bleeds and wounds that heal slower than normal. Swollen, tender joints and aching bones, general weakness, loss of appetite and dry, scaly skin.

VITAMIN D
Functions:
-essential in the formation and maintenance of bones and teeth by regulating the absorption and use of calcium and phosphorus.
-It also aids in the maintenance of a healthy nerve and muscle system.

Sources: Sunlight, fortified milk and margarine, eggs and butter, Cod liver oil

Signs of Deficiency: A prolonged lack of this nutrient results in changes in the bones of children and adults

MINERALS
CALCIUM- 1 gram/day

• Needed for building of strong bones and teeth

• Sources : Cereals, green vegetables, eggs, fruit

  IRON- 0.02 gram/day

• Needed for haemoglobin formation

• Sources : Liver, meat, eggs, bread, green vegetables

• Deficiency in iron causes anaemia & eventually fatigue

DIETARY FIBER
• Indigestible, e.g. cellulose

• Aids in bowel movements

• Prevents constipation

• Sources : fresh fruits, vegetables, bran, cereals, wholemeal bread