October 21st is observed as World Iodine Deficiency Day. The aim is to create awareness about the adequate use of iodine and highlight the consequences of iodine deficiency.
Iodine is an essential micronutrient which is required for normal thyroid function and proper growth and development. However, iodine deficiency disorders are one of the biggest worldwide public health concern as of today. According to a recent report on the global status of iodine, around 1.88 billion people are at risk of iodine deficiency and 241 million school children have an inadequate iodine intake. So on this World Iodine deficiency day, let us help you understand a bit about iodine deficiency and its symptoms. Here are 9 things you should know about Iodine deficiency.
What is iodine deficiency?
Iodine is a trace mineral which is vital for the synthesis of thyroid hormones namely – triiodothyronine (T3) and thyroxine (T4).
According to the National Institute of Nutrition (NIN), the recommended daily dietary allowance of iodine for kids, adults and pregnant women are:
Infants and children (0 months – 6 years): 90 microgram
Children (6 years – 12 years): 120 microgram
Adolescents and adults: 150 microgram
Pregnant and lactating women: 250 microgram
Unlike other common nutrients such as iron and calcium, iodine does not occur naturally in large quantities in foods. It is present in the soil and hence, foods grown in iodine-rich soil contain good amounts of iodine. It is available in trace amounts in water, food, and salt. The common sources of iodine include sea fish, green vegetables, milk, meat, cereals, and salt. Due to the increasing incidences of iodine deficiency, common salt fortified with iodine is available in the market.
An inadequate intake of iodine through diet can lead to insufficient production of thyroid hormones. These hormones help regulate the functioning of various organs such as the heart, liver, and kidneys. It is also needed for the growth and development of the brain, especially during the fetal stage. So lack of the mineral iodine can result in numerous health conditions which are collectively termed as iodine deficiency disorders. The common health complications caused due to severe iodine deficiency include hypothyroidism, goiter and pregnancy-related problems such as stillbirth, miscarriage, preterm delivery, and congenital abnormalities in babies.
What are the signs and symptoms of iodine deficiency?
According to the American Thyroid Association, all the symptoms of iodine deficiency are related to its effect on the thyroid gland. This is because the thyroid gland traps and concentrates iodide (iodine enters the body in the form of iodide) which is used to synthesize and store thyroid hormones. When iodine requirements are not met, the thyroid gland finds it difficult to synthesize a sufficient amount of thyroid hormones. This, in turn, causes the gland to grow in size (goiter) and cause hypothyroidism. Read 7 Complications Of Hypothyroidism.
Here are some of the common signs and symptoms of iodine deficiency:
1. Swelling of the neck: Also known as goiter, it is one of the most common symptoms of iodine deficiency. When the body is low on iodine, the thyroid gland (which is situated in the neck region) fails to make enough thyroid hormones to meet the demand. So to meet the demand, the gland works harder, which causes the thyroid cells to grow and multiply, causing the gland to grow in size, which in turn leads to swelling of the neck.
2. Feeling weak and tired: This is the most common symptoms of hypothyroidism caused due to iodine deficiency. According to a 2017 Indian study on hypothyroidism, it was reported that around 95% of people suffering from low thyroid and iodine levels experience weakness and lethargy. It could be attributed to the fact that thyroid hormones play a key role to maintain energy levels in the body. So lack of the hormone can cause a drop in your energy levels and leave you feeling lethargic and weak.
3. Unexplained weight gain: The thyroid hormones also help control metabolism. So lack of iodine causes low levels of thyroid hormones, which affects the speed at which the body burns calories. As a result, the body burns fewer calories and stores the excess calories in the form of fat, causing you to gain weight.
4. Hair loss: Most of us are aware of the fact that low levels of thyroid can lead to hair loss. This is because thyroid hormones aid in the growth of hair follicles. Hence, lack of iodine and thus low thyroid levels can stop the hair follicles from growing, which over time can lead to significant hair fall.
5. Dry and coarse skin: More than 85% of the population with low thyroid and iodine levels can experience dry and harsh skin reported a 2017 study done by Indian researchers. Thyroid hormones not only help the skin cells to regenerate but also help to keep the skin hydrated by regulating the sweat mechanism. Thus, people with low thyroid levels tend to sweat less, which makes them more prone to dry skin.
6. Impaired memory: It is reported that iodine deficiency can cause brain damage in children which can lead to learning disability and psychomotor impairment which includes difficulty in remembering (memory), speaking, talking, and thinking. This is because thyroid hormones help the brain to grow and develop and lack of this hormone due to insufficient iodine can lead to cognitive impairment.
Moreover, an insufficient supply of thyroid hormones to the developing brain can lead to mental retardation. In pregnant women, brain damage and irreversible mental retardation of the growing fetus are some of the common complications induced by iodine deficiency.
7. Intolerance to cold: Low levels of thyroid hormones can affect the metabolism and lead to less heat production, making you feel sensitive to cold. Moreover, the low metabolic rate and low body temperature can make you more prone to feeling cold. It is seen that almost 84% of people with low thyroid levels experience cold intolerance.
Hence, ensure your daily recommended dose of iodine is fulfilled through your diet either from natural sources or fortified foods (or salts). And if you experience any of these symptoms of iodine deficiency it is wise to consult a doctor to know the exact cause of the disease and get it treated at the earliest.
(The article is reviewed by Dr. Lalit Kanodia, General Physician)
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