NutriVals is a free database of Nutrition Facts.

Iodine (I)

What is Iodine?

Iodine is a natural mineral found in the earth's soil and ocean water and it is an essential component of the thyroid hormones.

Why Does The Body Require Iodine?

It performs a number of important functions in the body, such as:

  • It regulates thyroid hormones namely triiodothyronine (T3), thyroxine (T4) and thyroid stimulating hormone (TSH), which are essential in controlling metabolism and heart health.
  • It develops the fetal brain and bone structure during pregnancy.
  • It develops the infant's cognitive abilities during the nursing period.
  • It regulates body temperature with the help of thyroid hormones, by dilating the blood vessels and allowing warm blood to move freely.
  • It maintains a healthy body weight by increasing metabolism.
  • It maintains blood cholesterol levels as T3 aids in the breakdown of cholesterol.
  • It keeps skin, hair and nails healthy by rejuvenating the lower layer of the skin.
  • Iodine regulates skin's moisture levels to help skin repair, hence it aids in the healing of cuts and bruises.

What Is The Daily Requirement of Iodine In Your Diet?

The Recommended Daily Intake of Iodine (RDI) for a human body is age-specific. The daily requirement for different age groups is as follows:

  • Infants (0-6 months): 110 mcg/day
  • Infants (6-12 months): 130 mcg/day
  • Children (1-8 years): 90 mcg/day
  • Children (9-13 years): 120 mcg/day
  • Adults : 150 mcg/day
  • Pregnant Women: 220 mcg/day
  • Nursing Women: 270 mcg/day

Note: mcg = microgram = 0.000001 grams

Which foods are rich in Iodine?

Iodine is found in a variety of routine food sources such as:

  • Iodized Table Salt
  • Animal-protein Foods
    • Saltwater Fish: Tuna, Codfish, Oysters, Shrimps
    • Chicken
    • Beef liver
    • Eggs
  • Plant-based Foods
    • Seaweeds: Nori, Wakame, Kombu Kelp
    • Prunes
    • Lima Beans
  • Dairy Milk Yoghurt Cottage Cheese Cheddar Cheese
  • Fortified Foods (Bread Cereals Infant Formula Milk Fruit Juice)

What Happens When There's A Lack Of Iodine In Your Body?

The levels of Iodine lower than RDI (Recommended Daily Intake) by roughly around Half i.e. 75 mcg/day or even lower than this is considered dangerous.

When your system is deficient in Iodine, the thyroid gland would not produce enough thyroid hormones leading to a condition called Hypothyroidism.

Hypothyroidism causes the thyroid gland to enlarge, sometimes thrice its original size. This can result in a condition called Goitre (A lump or swelling in the neck).

The other signs of the deficiency of Iodine in the system include,

  • Constipation
  • Fatigue / Lethargy
  • Dry Skin and Nails
  • Thinning of Hair
  • Sensitivity to Cold

What Happens When There's An Excess Of Iodine In Your Body?

The levels of Iodine higher than RDI (Recommended Daily Intake) by roughly around Double i.e. 300 mcg/day or higher than this (other than pregnant or nursing women) is considered dangerous.

When your system has a surplus amount of Iodine, it leads to a condition called Iodine-induced Hyperthyroidism.

The most common outcome of Hyperthyroidism is Thyroiditis (Thyroid Papillary Cancer).

The other signs of an excess of Iodine in the system include:

  • Burning of mouth, throat and stomach
  • Vomiting and Diarrhea
  • Nausea
  • Delirium
  • Coma

Lesser Known Facts About Iodine

Most people in the world get their dietary Iodine from milk.

Iodine is used as a contrast agent to get clearer images of the tissues during X-rays, MRI and CT Scan because it absorbs radiation.

Iodine is an amazing antiseptic.

Liquid Iodine was used to make the first-ever photograph.

Iodine is used as a preservative in water-based paints as it has antifungal properties.

Liquid iodine is used in science labs to test for starch.

Precaution: Never take Iodine Supplements without consulting with a doctor.

Iodine supplements may interact with blood pressure medication and diuretics leading to Hyperkalemia (Potentially fatal accumulation of Potassium in the blood cells).

Food high in Iodine (I)

This list shows food that are top sources of Iodine (I) and the quantity of Iodine (I) in 100g of food

Iodine (I)
0.005 mg
Fruit Vegetables Meat Dairy Eggs Bread Superfood Legumes Cereals Nuts and Seeds Seafood Other Spices and Herbs
Macronutrients Carbohydrate Fat Protein Water Fiber
Vitamins Thiamin (B1) Riboflavin (B2) Niacin (B3) Pantothenic Acid (B5) Pyridoxine (B6) Folate (B9) Cobalamine (B12) Ascorbic Acid (C) Vitamin A Vitamin K Vitamin E Vitamin D
Minerals Calcium (Ca) Iron (Fe) Magnesium (Mg) Phosphorus (P) Potassium (K) Sodium (Na) Zinc (Zn) Copper (Cu) Manganese (Mn) Iodine (I) Selenium (Se) Fluoride (F)
Amino acids Arginine Histidine Lysine Aspartic Acid Glutamic Acid Serine Threonine Asparagine Glutamine Cysteine Selenocysteine Glycine Proline Alanine Isoleucine Leucine Methionine Phenylalanine Tryptophan Tyrosine Valine