Why do you need it?
You need iodine for your thyroid gland to make the thyroid hormones T4 (thyroxine) and T3 (triiodothyronine) needed for normal growth and development. Low iodine intake is one of the most common nutritional deficiencies, despite it being one of the most preventable causes of impaired development in children. Too much iodine can disrupt your thyroid function leading to weight gain, an underactive thyroid (hypothyroidism) or an overactive thyroid (hyperthyroidism). Intakes of up to 500 micrograms a day of iodine are unlikely to cause harm.
Deficiency
In infants, iodine deficiency during early pregnancy can lead to severe physical and mental impairment, a condition known as congenital iodine deficiency syndrome (previously known as cretinism). In older people, symptoms of deficiency include an enlarged thyroid gland (goitre – a lump or swelling at the front of the neck), tiredness, weight gain, increased susceptibility to infections, depression, feeling cold at all times and dry and cracked skin.
How much do you need?
The World Health Organisation (WHO) recommends 150 micrograms (μg) of iodine a day for adolescents and adults, from 13 years of age through adulthood. The recommended intakes for infants, children, pregnant and lactating women are given below.
Recommended nutrient intakes for iodine. Click to read more…
| Age group | Recommended nutrient intake μg/day |
|---|---|
| Infants and children | |
| 0-59 months | 90 |
| 6-12 years | 120 |
| Adolescents and adults, from 13 years of age through adulthood | 150 |
| Pregnant women | 200 |
| Lactating women | 200 |
Where to find iodine
Iodine is found in seawater, rocks and some types of soil. The amount of iodine in plants depends on how much there is in the soil in which they grow just as the levels in meat and dairy products reflects the amount of iodine used in animal feed. The best plant sources of iodine include sea vegetables and iodised salt.
- Seaweed: Although not as commonly consumed in Uganda as in coastal regions, seaweeds provide a rich source of iodine. Packets of dried arame, wakame or nori can be bought and a small amount sprinkled into soups, stews, curries etc regularly.
- Iodised salt: In 1993, the Ugandan Government introduced a policy of universal salt iodisation requiring all household salt to be iodised. Commonly used in Uganda, iodised salt can be a significant source of iodine in the diet. Use sparingly though as salt can increase blood pressure and the risk of heart disease.
- Vegetables: Some vegetables grown in iodine-rich soil may contain iodine but the amount varies depending on the soil. Examples include wholegrains, green beans, kale and potatoes with skin. Amounts tend to be low and variable.
- Pulses: Peas, beans and lentils may contain iodine, although the amounts may be low compared to seaweed and iodised salt.
- Fruits: Some fruits, such as strawberries and bananas, may contain trace amounts of iodine.