Iodised salt can prevent iodine deficiency

Iodised salt can prevent iodine deficiency

ZIMSEC O Level Combined Science Notes: Deficiency Diseases

  • A person might suffer from a deficiency disease if their diet lacks certain essential minerals and vitamins
  • Two essential minerals and vitamins are:
  • Iodine and
  • Vitamins


Goitre is a sign of iodine deficiency. Image credit

Goitre is a sign of iodine deficiency. Image credit

  • Is a naturally occurring mineral element
  • However some people do not get it in enough quantities naturally
  • Iodine is required by the thyroid gland found in the neck
  • As part of the body’s metabolism in order to make a substance known as thyroxine which regulates growth and development

Symptoms of iodine deficiency

  • In children there might be stunted physical and mental growth
  • Adults might develop a goitre
  • A goitre is a swelling of the thyroid gland.
  • In children mental development might slow down their physical and mental development
  • Resulting in children referred to as cretins

Overcoming iodine deficiency

  • This can be overcome by using iodised salt

Vitamin A

  • Is found in foods like fresh vegetables and liver

Symptoms of Vitamin A deficiency

  • Poor development of the trachea lining
  • This results in opportunistic infections of the trachea and bronchi
  • Poor night vision/Night blindness

Overcoming the deficiency

  • Eating food rich in vitamin A
  • Such foods include  dairy produce (cheese, milk, ice cream etc), carrots, cabbage and tomatoes

NB All these deficiency symptoms and others can be avoided by eating a balanced diet.

To access more topics go to the Combined Science Notes page.