PAKISTAN is considered one of the most iodine-deficient countries in the region. Iodine is an essential trace mineral needed by the body. Seafood is one of the best sources of iodine. Saltwater fish contain higher concentration of iodine than freshwater fish. The dairy industry adds iodide to cattle feed and uses sanitising solutions that contain iodide. These measures add substantial amounts of iodine to milk and dairy products.

Iodised salt, used in cooking, is the primary source of iodine for many people. It adds 35-70 micrograms of iodide to an average adult’s daily diet. After salt, dairy products supply most of our dietary iodine, followed by 10-15 per cent from meat, fish and poultry, and 5-15pc from grain and cereals. The total amount of iodine in the body of an average adult is about 75 micrograms per day which should be sufficient.

However, the World Health Organisation’s (WHO) recommended dietary allowance (RDA) of iodine is as follows: adults and adolescents 150mcg per day; pregnant and lactating women 250mcg per day, and children aged 6-12 years 120mcg per day.

Dietary iodine is absorbed in the small intestine in the form of iodides. Deficiency of iodine inhibits synthesis of thyroid hormone, as the body senses lack of thyroid hormones and produces more and more thyroid stimulating hormone (TSH) causing the thyroid gland to grow, resulting in goitre which has been linked to depressed IQ, in addition to usual symptoms of hypothyroidism, cold intolerance, weight-gain, sluggishness and decreased body temperature.

Severe iodine deficiency during early pregnancy leads to miscarriage, stillbirth, stunted growth and cognitive impairment. Contrarily, high consumption of iodine results in overactive thyroid. The gland produces too much of thyroid hormone, causing unintentional weight-loss and rapid irregular heartbeat. Therefore, it is imperative to consume a balanced iodine diet.

Dr Kousar Karimi
Karachi

Published in Dawn, April 24th, 2022