Signs and Symptoms of Iodine Deficiency

Iodine is one of the essential minerals commonly found in seafood. The thyroid gland uses iodine to produce thyroid hormones, which help control growth, repair damaged cells, and promote a healthy metabolism. Unfortunately, research shows that about one-third of people worldwide are at risk of iodine deficiency.

Individuals at highest risk include:

• Pregnant individuals
• Individuals living in countries where the amount of iodine in the soil is very low, including South Asian countries, Southeast Asia, New Zealand, and European countries
• Individuals who do not use enough iodized salt
• Individuals who follow a vegan or vegetarian diet

Iodine deficiency can cause uncomfortable and even severe symptoms, such as swelling in the neck, weight gain, pregnancy problems, and learning difficulties. These symptoms are very similar to those of hypothyroidism or low levels of thyroid hormones. Since iodine is necessary for producing thyroid hormones, a deficiency in iodine means that the body cannot make enough thyroid hormone, resulting in hypothyroidism.

Signs and symptoms of iodine deficiency in the body

• Swelling in the neck

The most common symptom of iodine deficiency is swelling in the front of the neck, a condition known as goiter. Goiter occurs when the thyroid gland becomes too large. The thyroid gland is a small butterfly-shaped gland that produces thyroid hormones in response to signals from thyroid-stimulating hormone (TSH). When TSH levels in the blood rise, the thyroid gland uses iodine to make thyroid hormones.

If the body has low levels of iodine, the thyroid gland cannot produce enough hormones. In order to compensate for this deficiency, the thyroid gland works harder, causing the growth and proliferation of cells that eventually lead to goiter. Fortunately, most cases of goiter can be treated by increasing iodine intake. However, if left untreated for a long period of time, goiter may cause permanent damage to the thyroid gland.

• Unexpected weight gain

Unexpected weight gain is a common symptom of goiter and iodine deficiency. When the body lacks sufficient iodine to produce thyroid hormones, weight gain can occur. Thyroid hormones play a crucial role in controlling the body’s metabolic rate. Low levels of thyroid hormones lead to the body burning fewer calories at rest, causing more calories to be stored as fat. Increasing iodine intake in the diet may help reverse these metabolic effects, by aiding the body in producing more thyroid hormones.

• Fatigue and weakness

Fatigue and weakness are common symptoms of goiter and iodine deficiency. Some studies have shown that approximately 80% of people with low thyroid hormone levels, feel tired, sluggish, and weak. Thyroid hormones play a crucial role in energy production in the body. When thyroid hormone levels are low, the body cannot produce as much energy as usual, leading to a sharp drop in energy levels and feelings of weakness.

• Hair loss

Thyroid hormones regulate the growth of hair follicles. If levels of thyroid hormones are low, hair follicles may stop regenerating, leading to hair loss over time. Consequently, individuals with iodine deficiency may also experience hair loss. In cases where hair loss is due to iodine deficiency, ensuring an adequate intake of this mineral may help prevent further hair loss by correcting thyroid hormone levels.

• Dry and flaky skin

Dry and flaky skin is a common issue for individuals with iodine deficiency. This is because thyroid hormones, which require iodine, play a crucial role in the regeneration of skin cells. When levels of thyroid hormones are low, skin regeneration is less frequent, resulting in dryness and flaking. Furthermore, thyroid hormones also help regulate sweat production in the body. Individuals with lower levels of thyroid hormones, such as those with iodine deficiency, tend to sweat less than those with normal levels. Since sweat helps keep the skin moisturized and hydrated, this decrease in sweat production can contribute to dry skin, making it a common symptom of iodine deficiency.

• Feeling colder than usual

Feeling cold could be a sign of iodine deficiency. Research suggests that over 80 percent of individuals with low thyroid hormone levels may experience increased sensitivity to cold temperatures. Thyroid hormones play a crucial role in regulating the body’s metabolic rate, so low levels can slow metabolism and decrease heat production, leading to feelings of coldness. Additionally, thyroid hormones stimulate brown fat activity, which is responsible for generating heat. Therefore, iodine deficiency, including low thyroid hormone levels may hinder brown fat function, further contributing to feeling colder than normal.

• Changes in heart rate

Heart rate is the number of times the heart beats per minute and may be affected by iodine levels. A small amount of this mineral can slow down the heartbeat, while an excessive amount can increase the heart rate. A severe iodine deficiency may cause an abnormally slow heart rate, resulting in feelings of weakness, fatigue, dizziness, and possibly fainting.

Alt: Signs and Symptoms of Iodine Deficiency

• Difficulty in learning and remembering

Iodine deficiency can impact one’s ability to learn, remember and recall information. A study involving more than 1000 adults found that individuals with higher levels of thyroid hormones performed better on learning and memory tests than those with lower levels of thyroid hormones. Thyroid hormones play a significant role in brain growth and development, which is why iodine deficiency can hinder brain development. Research has indicated that individuals with low thyroid hormone levels may have a smaller hippocampus, the part of the brain responsible for long-term memory.

• Problems during pregnancy

Pregnant women are at a high risk of iodine deficiency because they need to consume enough iodine to meet their daily needs as well as the needs of their growing baby. The increased demand for iodine continues during lactation, as infants receive iodine through breast milk. Not consuming enough iodine during pregnancy and breastfeeding may cause side effects for the mother and fetus. Mothers may experience symptoms of hypothyroidism such as goiter, weakness, fatigue and feeling cold. Iodine deficiency in infants may hinder physical and brain development. Additionally, severe iodine deficiency may increase the risk of stillbirth.

• Heavy or irregular periods

Heavy and irregular periods may occur as a result of iodine deficiency. Like many symptoms of this issue, it is linked to low levels of thyroid hormones. According to studies, 68% of women with low thyroid hormone levels experienced irregular menstrual cycles and more frequent periods with heavy bleeding. Low levels of thyroid hormone disrupt the signals of hormones involved in the menstrual cycle.