• Download App

Iodine: Function, Deficiency and Sources

Iodine is a trace mineral required to produce thyroid hormones and maintain normal functioning of the thyroid gland. Thyroid hormones are essential for various physiological processes, including metabolism, growth, development and other functions.


Following individuals are at the risk of developing iodine deficiency:

  • Who is not using iodized salt
  • Pregnant women.
  • Who are living in regions with iodine-deficient soils such as mountainous areas like Himalayas and river valleys of Southeast Asia
  • Who consume goitrogen – a substance that interferes with iodine absorption. These are present in soy, cabbage, broccoli, cauliflower, etc. However, if one is taking adequate amounts of iodine, eating a moderate amount of goitrogen need not be a concern.



idoized salt, salt

The natural sources of iodine include:

  • Iodized salt.
  • Seafood is rich in iodine like fish (cod and tuna), seaweed, shrimp, etc.
  • Dairy products: Milk, yoghurt, and cheese.
  • Bread, cereals, fruits and vegetables depending on the amount of iodine present in the soil and fertilisers used.

Recommended Daily Intake (RDA)

The Indian RDA (based on WHO-UNICEF-ICCIDD recommendations) for iodine are:

  • Infants: 90 mcg
  • Children(1+ to 5+ years): 90 mcg
  • School going children(6+ to 11+ years): 120 mcg
  • Adolescents and adults: 150 mcg
  • Pregnant women and lactating women: 200 mcg


Iodine deficiency can cause:

  • Goitre (enlargement of thyroid gland) or hypothyroidism.
  • Anovulation and infertility
  • High blood pressure in pregnant women
  • Mental retardation in babies whose mothers did not get adequate iodine during pregnancy
  • Cretinism (underdeveloped physical and mental growth in children)

Iodine Supplement

Supplements are recommended for those who have deficiencies:

  • Iodine is available in the form of potassium iodide or sodium iodide as dietary supplements. Several multivitamin-mineral supplements also contain iodine.

Can Iodine be harmful

Yes, consuming supplements more than the recommended quantity can lead to harmful effects like goitre, thyroid cancer, thyroid gland inflammation, burning sensation in the throat and stomach, fever, stomach pain, nausea, vomiting, diarrhoea, weak pulse and coma.

Drug interactions

It is suggested to watchful while using iodine supplements as it can interact with other medications:

Avoid taking iodine supplements if you are taking anti-thyroid medications for an overactive thyroid (hyperthyroidism) as it can decrease thyroid levels.

Taking iodine supplements for high blood pressure like ACE inhibitors and water pills (diuretics) can increase potassium levels in the blood.

Hence, consult your doctor if you are on any medications before using any of the iodine supplements.

Consult a top Dietitian/Nutritionist

Copyright © 2018 Modasta. All rights reserved


Email this to someoneShare on LinkedInTweet about this on TwitterShare on Google+Share on Facebook
  •  Iodine. National Institutes of Health. https://ods.od.nih.gov/factsheets/Iodine-Consumer/. Accessed on November 18,2016.
  • Iodine in diet. U.S. National Library of Medicine. https://medlineplus.gov/ency/article/002421.htm. Accessed on November 18,2016.

Add a Comment

You must be logged in to post a comment

Recommended For You

More On This Category

Our Partners