Iodine is an essential part of everyone’s diet.
It is not naturally made by the body, so it should be obtained through food or supplements. Also, iodine is just a natural content of some foods and an added formula for supplements and certain salt seasonings.
Moreover, iodine is required by the body to produce thyroid hormones, namely thyroxine and triiodothyronine. This essential nutrient can assist with the creation of proteins and enzyme activity, including regulating normal metabolism.
When your body lacks iodine, your thyroid hormones may not work properly, which can further lead to an underactive or overactive thyroid gland. Not having enough iodine can cause the development of medical conditions of hypothyroidism and hyperthyroidism with different negative side effects in the body .
Effects of iodine on health
Health experts are studying and investigating iodine to know its effects on health. Here are a few examples of some research about the effects of iodine:
Fetal and infant development
Pregnant women or breastfeeding should have enough iodine for their infant to grow and develop properly. Breastfed babies acquire iodine from their mother’s breast milk. However, the iodine content of breast milk is based on how much iodine the mother consumes.
In order to produce adequate amounts of iodine for proper fetal and infant development, it is recommended by several national and international groups that pregnant and breastfeeding women and babies must take iodine supplements.
The American Thyroid Association suggests that pregnant women, women who are planning to become pregnant or breastfeeding, must take a supplement containing 150 mcg of iodine as potassium iodide every day.
On the other hand, the American Academy of Pediatrics has backed up the recommendation and advised women with the same guidelines. Nonetheless, there are only a few that has iodine content in the prenatal multivitamins sold in the United States.
Consequently, pregnant women definitely need more iodine in their diet than normal people do. Iodine is particularly essential for the proper brain development of infants.
Research suggests that infants born to women who lack enough iodine during pregnancy are at a high risk of experiencing intellectual delays and having lower IQs compared with children born to mothers who have enough iodine during pregnancy .
Moreover, breastfeeding mothers require higher iodine content as they supply their babies with minerals through breast milk. As the mother gets enough iodine, she ensures that the infant also acquires enough iodine for their development, especially for proper brain development.
Consuming sufficient iodine during pregnancy can contribute to healthy birth weight. A research study about pregnant women with goiters showed that more iodine intake could correct goiters and result in an improvement in birth weight .
Fibrocystic breast disease
This noncancerous disease can cause lumpy, painful breasts and is normally not harmful. Fibrocystic breast disease primarily affects women of reproductive age but can be experienced by those in the menopausal stage.
High doses of iodine supplements can lower the pain and other signs and symptoms of fibrocystic breast disease; however, a more extensive study is needed to confirm the claim.
You should check with a health professional before taking iodine for fibrocystic breast disease because iodine can be harmful at high doses for some people.
Cognitive function during childhood
As mentioned, babies’ brains can be properly developed through iodine intake, and this health benefit can be further extended to early childhood. Kids who don’t acquire enough iodine are at a high risk of intellectual disabilities.
Severe iodine deficiency that occurs in childhood may have harmful effects on the development of the brain and nervous system in children. Meanwhile, mild iodine deficiency during childhood is more difficult to measure but might only cause subtle problems with neurological development.
Having children with mild iodine deficiency take iodine supplements may improve their reasoning abilities and overall cognitive function. Also, iodine supplements are known to improve both physical and mental development. More research study is required to deeply understand the effect-relationship between mild iodine deficiency and iodine supplements on cognitive function.
Thyroid cancer induced by radiation
Nuclear accidents may release radioactive iodine into the environment, which may increase one’s risk of thyroid cancer, especially for those who are exposed to radioactive iodine.
Iodine-deficient individuals who are also exposed to radioactive iodine are particularly at a high risk of developing thyroid cancer. The United States Food and Drug Administration has approved the use of potassium iodide as a thyroid-blocking agent in lowering the risk of thyroid cancer in radiation emergencies.
People with thyroid cancer may be treated through radioactive iodine. The thyroid absorbs nearly all of the iodine a person takes in. Having radioactive iodine may damage thyroid cells, like the cancerous ones, and those not removed by surgery.
Iodine intake may also help increase the lifespan of individuals who have differentiated thyroid cancer that has spread to some parts of the body.
A goiter refers to an enlarged thyroid that often occurs as a result of hypothyroidism, which is an underactive thyroid, or hyperthyroidism meaning overactive thyroid.
The most common cause of goiter is a lack of iodine in the diet. Goiter may also occur as a result of certain medical conditions, like Hashimoto’s or Grave’s diseases.
In certain instances, a goiter may also develop as a result of a genetic defect, injury or tumor. Having enough iodine may help prevent the development of dietary-related goiters.
How much iodine do you need?
Generally, people of varying ages require different amounts of iodine. The National Institutes of Health  suggests the following daily averages:
|Life stage||Recommended amount|
|Birth to 6 months||110 mcg|
|Infants 7 to 12 months||130 mcg|
|Children 1 to 8 years||90 mcg|
|Children 9 to 13 years||120 mcg|
|Teens 14 to 18 years||150 mcg|
|Pregnant teens and women||220 mcg|
|Breastfeeding teens and women||290 mcg|
What happens if you lack iodine?
People who are low in iodine may develop iodine deficiency, which is a condition that impairs the normal functioning of the thyroid.
It also usually further results in hypothyroidism, which is a health condition in which our bodies cannot produce enough thyroid hormones.
The consequences in health of hypothyroidism may vary widely between individuals; however, it commonly involves weight gain, over-tiredness, intolerance to colds and swelling of the face and some body parts.
People who have deficient levels of iodine may experience the opposite effect, which may force their thyroid to work even harder and produce more thyroid hormones.
The overstimulation of the thyroid gland hyperthyroidism can promote growth and swell in the neck, which is an apparent physical appearance of having goiter.
The effects of hyperthyroidism are widely different between individuals but may also include anxiety, weight loss, increased appetite, intolerance to heat, insomnia and heart palpitations.
Iodine deficiency may occur when the thyroid gland has an insufficient amount of iodine it needs to function properly. The thyroid gland refers to the butterfly-shaped gland that can be found in the front of the neck.
The thyroid makes thyroid hormones that are released into the bloodstream. Then, the blood carries the hormones to the body’s tissues. One of the first indications of iodine deficiency is the enlargement of the thyroid. The medical condition is called goiter.
The thyroid slowly grows larger as it tries to provide the body’s demand for more thyroid hormones. A person with goiter may experience the following symptoms:
- Difficulty swallowing
- Trouble breathing
The primary symptom of iodine deficiency is hypothyroidism. Hypothyroidism happens when the body’s iodine level is low, and the thyroid gland can’t make enough thyroid hormone.
The medical condition is also called underactive thyroid, which causes slow metabolism, resulting in fatigue, weight gain and the inability to tolerate colds.
Some other signs and symptoms of iodine deficiency include the following:
- Coarse, thinning hair
- Scaly, dry skin
- Puffy skin
Iodine deficiency may affect people’s health at any age, but it is more harmful to pregnant women and children. This is because a lack of iodine can impair a child’s growth and development, specifically the brain and cognitive development .
Best sources of iodine
Most countries rely on iodine fortification in order to encourage adequate dietary intake. In fact, there are over 70 countries that use iodized salt as their major source of iodine intake.
Moreover, just one-fourth teaspoon of iodized salt contains about 100 micrograms of iodine. However, processed foods that are known to contain a lot of salt typically do not contain iodine.
For you to spot whether the processed food has iodine, the manufacturers usually add them to the nutritional value table in the packaging. Therefore, you should focus on lowering the amount of salt you consume from processed foods and get your sodium from iodized salt.
Some natural sources of dietary iodine are seaweed, saltwater fish and seafood. Dairy products can also supply iodine in your diet, but they vary in content levels.
During lactation in women, the breast concentrates iodine in milk. Therefore, it makes breastmilk a great source of iodine as long as the mother’s iodine intake is enough .