10 signs and symptoms of iodine deficiency
[Article updated: May 2020]
Iodine is an essential mineral that is not synthesized by the body. It is used by the thyroid gland to produce thyroid hormones which control the growth and repair of damaged cells and which promote healthy metabolism.
According to statistics, about a third of the world's population suffers from iodine deficiency. The people most affected by this deficiency are largely:
- Pregnant women.
- Inhabitants of some countries where there is very little iodine in the soil such as South Asia, New Zealand and some European countries.
- People who use non-iodized salt.
- Vegetarians or vegans.
On the other hand, in the United States where the food supply is rich in minerals, we notice that the cases of iodine deficiency recorded are very rare.
Iodine deficiency can lead to unpleasant and even serious health complications. They include swelling in the neck, pregnancy-related problems, weight gain, and learning difficulties. Its symptoms are very similar to those of hypothyroidism.
Here are 10 signs and symptoms of iodine deficiency that you should not ignore.
1. Neck swelling
When the body lacks iodine, this gland does not make enough thyroid hormones. And to compensate for this lack, she doubles her effort to increase her production, which causes a goiter.
Fortunately, these cases can be easily treated by increasing the daily iodine intake.
However, if a goiter is not treated in time (for many years, for example), it could cause permanent damage to the thyroid gland.
2. Rapid and unexplained weight gain
Rapid weight gain is another sign of iodine deficiency. It usually happens when the body does not have enough iodine to make thyroid hormones.
This is because they are responsible for the rate of basal metabolism, the process by which the body converts food into energy and heat. If the level of these hormones is low, the body burns fewer calories and therefore they will be stored as fat.
Adding iodine to your diet can help reverse the effects of a slow metabolism.
3. State of fatigue and weakness
Feeling tired and weak is also a common symptom of iodine deficiency.
A study [ 1 ] showed that almost 80% of people who suffer from low thyroid hormone levels due to iodine deficiency , feel tired, lethargic and weak. thyroid hormones help the body produce energy.
The decrease in their level following an iodine deficiency has a negative impact on the energy reserves produced by the body and therefore leads to a state of fatigue and weakness.
4. Hair loss
Thyroid hormones help control the growth of hair follicles. The latter stop regenerating if the level of these hormones is low. Which can therefore lead to hair loss.
According to a study [ 2 ] conducted on 700 volunteers, 30% of people with low thyroid hormone levels suffered from loss of hair.
However, another study [ 3 ] found that low levels of thyroid hormones only appear to cause hair loss in people with a family history of hair loss.
If you suffer from hair loss from iodine deficiency, getting enough of this mineral can help correct thyroid hormone levels and stop hair loss.
5. Dry, scaly skin
Iodine deficiency can lead to dry, scaly skin.
In fact, some studies have found that up to 77% of people with low thyroid hormone levels may experience dry, scaly skin [ 1 ]. Thyroid hormones help skin cells regenerate.
Therefore, if their rate is low, this regeneration in turn weakens, which can lead to dry, scaly skin [ 4 ].
Plus, thyroid hormones help the body regulate sweating which helps keep the skin hydrated.
People with low thyroid hormone levels tend to sweat less than people with normal thyroid hormone levels [ 5 , 6 ].
6. Abnormal feeling of cold
In fact, some studies have found that over 80% of people with low thyroid hormone levels may feel more sensitive than normal to cold temperatures [1].
The reduced level of thyroid hormones causes a slowing down of the metabolism which results in a drop in thermogenesis and therefore in body heat [ 7 , 8 ].
In addition, thyroid hormones help stimulate the activity of your brown fat, a type of fat that is responsible for producing heat.
This means that low levels of thyroid hormones, which can be caused by iodine deficiency, could prevent brown fat from doing its job [ 9, 10 ].
7. Heart rate changes
Heart rate is the number of times the heart beats per minute. This frequency can be affected by the iodine levels in the body.
A deficiency in iodine could make the heart beat slower than usual, while a strong presence of this one could make it beat faster than usual [ 11 , 12 ].
Severe iodine deficiency can cause an unusually slow heart rate. This could make you feel weak, tired and dizzy.
In the extreme, it could lead to unconsciousness [ 13 ].
8. Learning and memory problems
Iodine deficiency can affect the ability to learn and remember.
Study of over 1,000 adults found those with higher thyroid hormone levels performed better on learning and memory tests than those with lower thyroid hormone levels [ 14 ].
Thyroid hormones help the brain to grow and develop. This is why a deficiency of iodine, which is necessary for the production of thyroid hormones, can reduce brain development.
In fact, studies have shown that the hippocampus, the part of the brain that controls long-term memory, appears to be smaller in people with low levels of thyroid hormones [ 15 ].
9. Problems during pregnancy
Pregnant women are at high risk of iodine deficiency.During pregnancy, a mother should consume enough iodine to meet her own needs and those of her baby. These needs must also be covered during the breastfeeding period.
Not getting enough iodine during pregnancy and breastfeeding can cause side effects in mother and baby.
Mothers may experience symptoms of an underactive thyroid, such as goiter, weakness, fatigue, and feeling cold.
Iodine deficiency in infants can stunt physical growth and brain development. In addition, severe iodine deficiency can increase the risk of stillbirth.
10. Iodine deficiency can also disrupt your period
Heavy and irregular menstrual bleeding can occur as a result of iodine deficiency.
Like most symptoms of iodine deficiency, this is also linked to low levels of thyroid hormones, since iodine is needed to make thyroid hormones.
In one study, 68% of women with low thyroid hormone levels had irregular menstrual cycles, compared to only 12% of healthy women [ 16 ].
Research has also shown that women with low levels of thyroid hormones experience more frequent menstrual cycles with heavy bleeding. This is because thyroid hormones disrupt the signals of hormones that are involved in the menstrual cycle.
Natural solutions to remedy iodine deficiency
There are very few good sources of iodine in the diet. This is one of the reasons iodine deficiency is common around the world.
The Recommended Daily Allowance (RDI) is 150 mcg per day. This daily allowance should meet the needs of 97-98% of all healthy adults.
However, women who are pregnant or breastfeeding need more. Pregnant women need 220 mcg per day, while nursing mothers need 290 mcg per day.
The foods below are excellent sources of iodine:
- Seaweed, whole leaf dried - 11-1.989% of the DJR
- Cod (85 g) - 66% of the DJR
- 1 Plain yogurt - 50% of the RDI
- Iodized salt, 1/4 teaspoon (1.5 g) - 47% of the RDI
- Shrimps (85 g) - 23% of the RDI
- 1 large egg - 16% of the DJR
- Canned tuna (85 g) - 11% of the RDI
- 5 Dried prunes - 9% of the DJR
Seaweed is generally a great source of iodine, but that depends on where it comes from. Seaweed from some countries, such as Japan, is rich in iodine.
Smaller amounts of this mineral are also found in a variety of foods such as fish, shellfish, beef, chicken, lima and pinto beans, milk and other dairy products.
The best way to get enough iodine is to add iodized salt to your meals. Half a teaspoon (3 g) during the day is sufficient to avoid a deficiency.
If you think you are iodine deficient, it is best to see your doctor who will check for signs of swelling (a goiter) or take a urine sample to check your iodine levels.