Iodine Deficiency: Everything You Need to Know

Iodine deficiency is related to problems in the thyroid gland. Let us know the recommended values of its intake and what is the treatment option.
Iodine Deficiency: Everything You Need to Know

Written by Josberth Johan Benitez Colmenares, 28 June, 2021

Last update: 28 June, 2021

Iodine deficiency is one of the most common causes of thyroid disorders. Its prevalence in the world is very high, due in part to this element’s uneven distribution on the planet. In general, it doesn’t cause obvious symptoms, at least until there are no complications in the body.

When its levels in the body are lower than daily requirements, people can develop iodine deficiency disorders. This can condition the quality of life, especially during childhood and pregnancy. Let’s see everything that we know about it and its treatment.

What is iodine?

Iodine deficiency causes thyroid problems
A balanced diet usually covers all iodine needs, at least under normal conditions.

Iodine is a natural chemical element in the same way as oxygen or iron. In general, we can find it in the ground and in the sea, but its distribution isn’t the same throughout the planet. The human body doesn’t produce it, but it does need it to perform some of its functions.

The amount of iodine you receive on a daily basis depends, among other things, on where you live. In theory, your body takes advantage of the water, vegetables, fruit, and meat that you eat. It’s an essential component of the hormones triiodothyronine and thyroxine, those secreted by the thyroid gland.

If your diet doesn’t provide the amount that the gland needs for the production of both hormones, then an imbalance is generated that can result in several types of disorder. Despite this, and its prevalence in the world (as we’ll see), few people are aware of its importance for the proper functioning of the body.

What are the daily iodine requirements?

According to the American Thyroid Association, 30% of the world’s population is deficient in iodine. According to the researchers, in a healthy person, levels should be between 15 to 20 milligrams. Of these, approximately 80% are located in the thyroid.

The World Health Organization (WHO) has established the following daily values for these three population groups:

  • School-aged children: Levels in their bodies should range from 100 to 199 μg / L. Levels below 99 μg / L are associated with several health complications.
  • Pregnant women: The appropriate values should be between 15o and 249 μg / L. Values less than 150 μg / L can compromise the development of the fetus.
  • Lactating women and children under 2 years of age: An average of 100 μg / L is suggested.

The recommendations for adults are 150 μg / L, with small oscillations as appropriate. It’s important to note that excessive consumption of this compound can also cause the same complications as its deficiency. Generally, concentrations above 300 μg / L are not considered good for health.

Symptoms of iodine deficiency

Under normal conditions, there’s no way to detect that iodine levels are low in the body. This is because it doesn’t produce visible symptoms, which prevents people from noticing its deficiency.

The Australian Thyroid Foundation (ATF) notes that the most common sign it generates is an enlarged thyroid gland, also known as a goiter.

You can usually notice this in the mirror, or by feeling the area of the lower mid-neck. Depending on how big it is, it can cause coughing, shortness of breath, or even problems swallowing food. In turn, symptoms may appear that alert the gland’s malfunction. These are the following:

  • Weight gain
  • Muscular weakness
  • Fatigue
  • Depression
  • Hair loss
  • Slow heartbeat
  • Constipation
  • Dry skin
  • Difficult to focus

Unfortunately, all of the above develop when iodine deficiency has reached critical levels. In pregnancy, for example, it can pose a serious risk to the health of the fetus. Let’s now find out all about this and other drawbacks related to low iodine levels in the body.

Complications of iodine deficiency

Iodine deficiency requires medical attention
Most of the problems related to iodine intake are related to the thyroid gland.

As we pointed out at the beginning, all the complications created by a deficiency of this chemical element are classified as iodine deficiency disorders. According to the evidence, the most serious ones are the following:

  • Adult: Impaired mental function, hypothyroidism, hyperthyroidism, goiter.
  • Children and adolescents: A delay in physical development, impaired cognitive ability, hypothyroidism, goiter.
  • Newborns: Neonatal hypothyroidism, endemic neurocognitive impairment, goiter.
  • Fetuses: Miscarriage, congenital anomalies, stillbirth, increased risk of perinatal death, cretinism (irreversible brain damage).

Studies and research are constantly alerting us to the danger that iodine deficiency represents in pregnancy and childhood. These are by far the most affected groups, with complications in many cases irreversible. Controlling their levels, therefore, should be a priority in order to avoid the manifestation of collateral effects.

Diagnosis and treatment of iodine deficiency

Iodine deficiency is diagnosed through a urine test. Based on the reference values that we have given previously, the specialist can determine whether or not the patient has a deficiency in this element. This is generally the standard procedure. It’s safe, fast, and isn’t invasive.

To complement this, however, experts can perform other types of tests. In short, these are aimed at determining the possible complications that the deficiency has caused. For example, imaging tests to assess the state of the gland if it has developed a goiter.

Blood tests can also alert doctors that the patient may be suffering from a thyroid disorder.

Generally, its treatment consists of correcting the deficiency through a diet with a high prevalence of iodine. Seafood (fish, seaweed, shellfish, shrimp), bread, fruit and vegetables, and dairy are good sources of iodine. However, it all depends on the presence of the element in your region.

If applicable, the specialist may suggest the intake of supplements. Certain problems caused, such as goiter, will be treated in a personalized way,  in this case with levothyroxine. Surgery may also be an option when the enlargement of the gland prevents the person from being able to breathe or swallow freely.

Researchers agree that iodine deficiency is the world’s leading preventable cause of mental retardation and brain damage. Children and pregnant or nursing women should be particularly careful. Monitoring is recommended to ensure that the values are close to those recommended by the WHO.

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