Diet & Deficiencies (Cambridge (CIE) IGCSE Biology)

Balanced Diet

• A balanced diet consists of all of the food groups in the correct proportions

• The necessary food groups are:

  • Carbohydrates

  • Proteins

  • Lipids

  • Vitamins

  • Minerals

  • Dietary Fibre

  • Water

Food Groups Table

Vitamin and Mineral Requirements Table

Varying Dietary Needs of Individuals Table

Scurvy & Rickets

Scurvy

• Scurvy is the name for a severe vitamin C deficiency

  • It is caused by a lack of vitamin C in the diet for over 3 months

• Its symptoms include:

  • Anemia

  • Exhaustion

  • Spontaneous bleeding

  • Pain in the limbs

  • Swelling

  • Gum ulcerations

  • Tooth loss

• It is a condition that was commonly seen in sailors between the 15th to 18th centuries

  • Long sea voyages made it very hard to access a ready supply of fresh produce

• Scurvy can be treated with oral or intravenous vitamin C supplements

Rickets

• Rickets is a condition in children characterised by poor bone development

• Symptoms include: 

  • Bone pain

  • Lack of bone growth

  • Soft, weak bones (sometimes causing deformities)

• Rickets is caused by a severe lack of vitamin D

  • Vitamin D is required for the absorption of calcium into the body

    • Calcium is a key component of bones and teeth

• Vitamin D mostly comes from exposure to sunlight but it can also be found in some foods (fish, eggs and butter)

• The treatment for rickets is to increase consumption of foods containing calcium and vitamin D

  • Alternatively vitamin D supplements can be prescribed