iodine deficiency

Iodine deficiency is one of the biggest public health concerns in the world today. Iodine deficiency occurs when there is a low concentration of iodine in food products; this leads to a corresponding low intake of iodine.

Since the body cannot produce its iodine, the iodine requirement must come from external sources. When the iodine requirement is not met, the thyroid may not be able to synthesize iodine, resulting in low levels of iodine in the blood.

Some of the implications of this are low IQ levels in children, impaired synthesis of thyroid hormone in both mother and child, mental retardation, hyperthyroidism, and goiter.

Iodine is an essential trace element found in most seafood, iodized salt, or taken as a supplement. It is a water-soluble mineral necessary for the production of thyroid hormone.

The thyroid hormones consist of thyroxine (T4 with four iodine molecules) and triiodothyronine (T3 with three iodine molecules). Since iodine is not produced naturally in the body, it must be found in the diet.

Iodine is vital for the healthy functioning of the thyroid gland. It synthesizes iodine to make thyroid hormones that help with the development of the brain, healing, growth, and metabolism.

The recommended daily iodine intake is 220 micrograms daily for pregnant women, and 290 micrograms daily for lactating women, and 150 micrograms daily for adults.

However, one-third of the world’s population is still at risk of iodine deficiency. About 2 billion people suffer from iodine deficiency, with approximately 50 million presenting physical symptoms, with the most vulnerable population being pregnant mothers and little children.

Goitre, the most visible manifestation of iodine deficiency, affects 187 million people globally as of 2010.

The thyroid gland synthesizes iodine. The thyroid gland is a butterfly-shaped gland situated at the lower front of the neck. It is necessary for the production of thyroid hormone, which is secreted into the blood and transported into all the tissues in the body.

Thyroid hormone helps the body use energy, stay warm, and helps the heart, muscles, brain, and other organs work to work correctly.

Signs and Symptoms of Iodine Deficiency

Putting on Weight

Unexpected weight gain is one of the apparent symptoms of iodine deficiency. It occurs when the body does not have sufficient iodine to synthesize thyroid hormones.

Thyroid hormones control the speed of metabolism, which is the process by which the body converts food into energy. A person with a healthy metabolism can burn excess calories.

However, low thyroid hormones slow down metabolic rest, which results in the body burning fewer calories. Excess calories in the body are then stored as fat. Adding more iodine reverses the effects of a decreased metabolic rate.


Goiter is the most well-known symptom of iodine deficiency. It appears as a swelling in the neck due to the thyroid gland increases in size.

When the intake of iodine is low, the production of thyroid hormone decrease; this results in an increased secretion of thyrotropin by the pituitary gland.

An increase in thyrotropin secretion stimulates more intake of iodine by the thyroid gland and a resulting growth of thyroid cells. This causes the enlargement of the thyroid gland, which eventually leads to goiter.

It can, however, be treated by increasing your iodine intake. On the other hand, if the goiter is not treated for many years, it may cause permanent damage to the thyroid gland.

Hair Loss

Loss of hair is a possible indicator of iodine deficiency. Thyroid hormones control the growth of hair follicles. Low thyroid levels may inhibit the regrowth of hair follicles, and this can lead to hair loss.

Hair loss caused by iodine deficiency can be remediated by increasing iodine intake. Sufficient consumption of this mineral would correct your hormone levels and stop hair loss.

Dry Skin

People with low thyroid hormone levels may be afflicted with dry, flaky skin. Several studies have shown that about 77 percent of low levels of thyroid hormone may experience dry and flaky skin.

Thyroid hormones, which consists of iodine, help regenerate your skin cells. When the thyroid hormone level is low, the regeneration does not occur fast enough. This leads to dry skin.

Furthermore, thyroid hormones aid the body in regulating sweat. People with low thyroid hormones due to lack of iodine tend to sweat less than people with normal thyroid hormone levels.


Fatigue is another common symptom of iodine deficiency. Studies have shown that about 80 percent of people with low levels of thyroid hormone, especially in cases of iodine deficiency, feel tired and exhausted.

These symptoms occur as a result of a slow metabolic rate caused by low thyroid hormone levels. The body cannot produce as much energy as it should. Thus, energy levels drop, leaving you feeling weak.

Low Body Temperature

Low thyroid hormone levels can leave you feeling colder than usual. This occurs as a result of iodine deficiency. Studies have shown that people with low levels of thyroid hormone are more likely to be sensitive to cold temperature compared to others.

Since thyroid hormones control the speed of metabolism, low thyroid hormone levels may cause it to slow down. Slow metabolism generates less heat required by the body, causing you to feel colder than usual.

Furthermore, thyroid hormones help in boosting the activity of your brown fat. Brown fat is a type of fat explicitly used by the body to generate heat. Low thyroid hormone levels caused by iodine deficiency inhibits brown fat from generating heat.

Antenatal Issues

Pregnant women are vulnerable to iodine deficiency. This is because they need to consume sufficient iodine to meet their daily requirements as well as that of the unborn child.

The increased demand for iodine continues even after the baby is born, as babies receive iodine through breast milk.

Insufficient intake of iodine during pregnancy and lactation may have side effects for both the mother and child.

The mother may experience symptoms such as fatigue, goiter, and feeling cold. Additionally, the baby’s physical and mental growth may be stunted.

Severe iodine deficiency may also increase the risk of stillbirth.

Heavy and Irregular Menstrual Flow

Iodine deficiency may cause heavy and irregular periods in women. This, like most symptoms of lack of iodine, is caused by low thyroid hormone levels.

Research shows that women with low levels of thyroid hormones experience menstrual cycles with heavy bleeding frequently. This is due to low thyroid hormones disrupting signals of hormones that regulate the menstrual cycle.

Mental Retardation

Low intake of iodine may affect your ability to learn and recall information. Studies comprising of over 1000 adults show that those with higher levels of thyroid hormones performed better in memory tests and learning than those with low thyroid hormone level.

Thyroid hormones influence the growth and development of the brain. Insufficient intake of iodine necessary to produce thyroid hormones may cause mental retardation.


A medical doctor performs diagnosis of iodine deficiency via a urine test.


Treatment of iodine deficiency occurs by increasing the intake of food with sources of iodine and the consumption of iodine supplements. According to the National Institutes of Health, the following are good sources of iodine:

  • Yogurt
  • Seaweed
  • Iodized salt
  • Seafood
  • Eggs
  • Dried prunes