What is the Importance of Iodine and What Can Happen If There Is Insufficient Iodine in the Diet?
One of the most crucial nutrients for the body is iodine. Our body can’t make it by itself so one needs to take it through diet. However, it is needed in quite a small quantity. It is a vital constituent of thyroid hormones. Insufficient iodine intake results in insufficient production of thyroid hormones. These hormones are helpful in maintaining the metabolic rate of the body. Most importantly, they help in the development of babies and support normal growth. Since iodine is crucial for the development of the brain, it becomes especially important that fetus and young kids consume a sufficient amount of it.
A large number of people get all the required iodine from food as it is present in food items like seaweed, dairy, and fish. It is mainly found in iodized salt. Moreover, it can be found in the soil of the earth, although the contents differ from one area to the other area. Therefore, the iodine content also differs in different produces.(1,2)
Iodine Deficiency and Its Effect on the Health
‘Iodine deficiency disorders’ is the term used for explaining the diverse range of effects of iodine deficiency. Human health can be affected badly if iodine consumption is low. Goitre (thyroid gland’s enlargement which results in neck swelling) has been found as one of the major health issues caused by iodine deficiency. Moreover, if the deficiency is severe, it may lead to intellectual disability and slow growth in kids. Many researchers have revealed that severe deficiency has negative effects on cognitive function and hearing capacity in kids.(1,3)
Let Us Have A Look At The Health Effects Of Iodine Deficiency:
Iodine Deficiency and Goitre
Neck swelling is one of the common complications associated with iodine deficiency. This swelling of the front of the neck is a result of the abnormally large size of the thyroid gland and is also known as goitre. The thyroid gland is responsible for the stimulation of the thyroid-stimulating hormone or the TSH. It is a butterfly-shaped small gland in front of the neck.
Higher blood levels of TSH is indicative that the body is making use of iodine for the production of thyroid hormone. This function is difficult to execute when the body is lacking in its iodine content. To make up for the low iodine availability, the thyroid gland works harder to produce and absorb more iodine from the bloodstream. This leads to an increase in the size and number of the cells, which eventually results in goitre.
Mostly iodine deficiency is treated by dietary changes and the inclusion of foods rich in iodine content. Although in patients with prolonged and untreated goitre, the damage caused to the thyroid gland can be permanent.(2,4)
Effects of Iodine Deficiency on the Growth of the Children
Iodine deficiency may lead to severe issues in the development of fetus, young babies and children. Babies are at risk if the pregnant woman is iodine deficient.
The deficiency of Iodine can have a negative impact on a child’s physical development. Behavioural and hormonal development is also affected. This can also result in intellectual disability.
In most developing nations, the lack of iodine has been identified as a possible cause of intellectual disability in kids. It can be prevented if the proper amount of iodine is provided.(5)
Iodine Deficiency Causes Weight Gain
If you have iodine deficiency, then you can gain weight unexpectedly. Weight gain can be a result of the unregulated metabolism of the body. Lack of proper amount of iodine in the body can lead to slowing down of metabolism and result in incredible weight. Since the calorie-burning speed of the body is slowed down, it leads to fat deposits in the body. This issue can be treated by incorporating higher amounts of iodine into the diet.
However, weight gain is not always the consequence of iodine deficiency. Increased calorie consumption can be one of the main factors. Lack of exercise can also be a reason.(6)
Iodine Deficiency Effect on Energy
Fatigue is another sign of iodine deficiency. It is usually accompanied by weakness. Studies suggest that patients having lower levels of thyroid hormones suffer from symptoms like weakness, sluggishness, and feel exhausted.
Thyroid hormones are also responsible for energy production by the body. These symptoms are the result of a lack of proper amount of thyroid hormones in the body resulting in lower energy levels and weakness. A study conducted on around 2500 people concluded that people with low thyroid hormone levels are prone to low energy levels.
Weakness resulting from low iodine levels also means that the patient may experience difficulty in moving, lifting, or performing any activity that includes weight. This is linked to a low metabolic rate in iodine-deficient patients. The decreased metabolism is associated with decreased energy as well as less efficient muscles.
However, weakness can be a symptom of various health issues and not just a result of iodine deficiency.(7,8)
Iodine Deficiency Impact on Heart Rate
Heart rate is the number of times the heart beats each minute. Iodine levels in the body can potentially impact the heart rate of an individual. A lower rate of iodine can lead to slowing down of the heart rate while too much iodine results in increased heart rate.
Very low levels of iodine in the body can lead to a slow heart rate. This slower rate of heartbeat can be accompanied by symptoms like dizziness, fatigue, weakness, and in some cases even lead to fainting.(9,10)
Iodine Deficiency and Hair Health
Thyroid hormones also impact hair follicles growth. Low levels of thyroid hormones negatively affect the regeneration rate of hair follicles.
Lower levels of thyroid hormones also impact the regeneration speed and capacity of hair follicles. Prolonged deficiency of this nutrient can eventually lead to hair loss. A study on about 700 people concluded that 30% of them experience hair fall as a result of iodine deficiency. Although some other researches also concluded that hair fall, as a result of iodine deficiency, is seen only in people having a family history of hair problems.
Get enough iodine if you suffer from hair loss due to deficiency of iodine and your hair will stop falling out as the level of thyroid hormone will be corrected in the body.(11)
Iodine Deficiency and Skin Health
Another common concern people with iodine deficiency experience is the flakiness of the skin. According to research, up to 77% of patients diagnosed with iodine deficiency also experienced skin concerns like dryness and flakiness.
Iodine in the thyroid hormone is an essential nutrient for the regeneration of skin and scalp. With low levels of iodine, the regeneration rate of these cells falls dramatically leading to various skin concerns.
In addition to its above-mentioned function, thyroid hormones are also responsible for the regulation of body temperature by making it sweat. Patients with lower levels of thyroid hormone or iodine tend to generate comparatively lesser sweat as compared to people with normal levels of this nutrient.
The decreased amount of sweat generation can also act as a contributing factor to drying skin. Since sweat is one of the sources of hydration for the skin, the decrease in its quantity acts as a trigger to dry skin.(12,13)
Feeling Colder Due To Iodine Deficiency
Another common sign of iodine deficiency is feeling colder than usual. Research suggests that about 80% of people who have been diagnosed with low levels of this essential nutrient tend to be more sensitive to lower temperatures than people with normal levels of iodine.
A reason for this sensitivity could be the slower metabolic rate that may be caused by the deficiency. A faster metabolism helps in the generation of heat in the body. However, slower metabolism is a reason for low body heat resulting in temperature sensitivity.(14,15,16)
Iodine Deficiency and Pregnancy Complications
Pregnancy often brings with it the risk of developing iodine deficiency. The increased risk is because the mother has to increase her iodine intake in order to meet hers as well as the baby’s needs. This period of need for increased iodine lasts throughout the pregnancy as well as the lactation period as the child get this nutrient via breast milk. If consumed in lower quantities than required, iodine deficiency can negatively impact the health of both the mother as well as the child.
If the iodine deficiency is moderate in a pregnant woman, it may Impact the hearing and physical development of the baby and may lead to learning issues. If the deficiency is severe, then it may lead to neurological and physical abnormalities, stillbirth, or miscarriage.
Iodine deficiency in mothers can be accompanied by signs of underactive thyroid. These include issues like fatigue, weakness, goitre, and lower body temperature. On the other hand, deficiency of iodine in new born babies can result in slower or poor brain development and slow physical growth. So, if a woman is pregnant, thinking of conceiving, or breastfeeding, she needs to consult with a doctor for her daily iodine requirement. The doctor may advise daily supplements for her.(2,17,18)
Iodine Deficiency and Its Impact on Learning Ability
Iodine is an important mineral and its deficiency can negatively impact learning and memorization ability. Research conducted on 1000 people concluded that people with higher levels of thyroid hormones had better learning and memorising ability. In comparison, people with low levels of thyroid hormone performed poorly. The conclusion was drawn with the help of tests conducted to monitor their performance.
The hormones that regulate the thyroid are also responsible for the growth and development of the brain. It is also the reason why iodine deficiency can impact brain development, as iodine is essential for the production of thyroid hormones.
Some studies indicate the difference in the size of the hippocampus in people with lower levels of thyroid hormones. It is found to be comparatively smaller in these people. Hippocampus is our brain’s part that is responsible for controlling long term memory.(19,20,21,22)
The Recommended Intake of Iodine in Your Diet
The required iodine intake varies according to age and other factors. We don’t need a huge amount of iodine like other nutrients as we need a comparatively low intake of this nutrient.
Below is given the Recommended Dietary Intake (in micrograms) one should have every day:
- 0 to 6 months old babies: 90 mg
- 7 to 12 months old babies: 110 mg
- 1 to 3 years: 90 mg
- 4 to 8 years: 90 mg
- 9 to 13 years: 120 mg
- 14 to 18 years: 150 mg
- 19 years and above: 150 mg
- Pregnant women: 220 mg
- Lactating women: 270 mg
Adequate Intake (AI) is considered for infants and babies, as the Recommended Dietary Intake (RDI) has not been established for them. This is an estimated iodine amount that is usually found in breast milk.(23)
Food Sources of Iodine
Seafood, eggs, dairy products, seaweed (kelp) and a few vegetables are some food items that contain iodine: The iodine content in these food items varies as per the place where it is grown and the way of preparing. Iodine is also used in cooking or already prepared meals. But, it is not suggested to add salt to meals since it might raise the risk of various health issues, including heart disease and high BP. In case you are adding salt to the already prepared meal, make sure you use iodized salt. So check the label before adding.
Since the year 2009, all commercialized bread products (excluding organic loaf and dough mixtures for preparing bread at home), in Australia, already have iodized salt added to them to enhance the iodine amount they have. This is referred to as iodine fortification of the bread. This implies that the majority of Australians (except pregnant women) are getting the required amount of iodine through their meals.(24,25,26)
Diagnosis of Iodine Deficiency:
The testing process for iodine deficiency starts with routine physical and urine tests. Alternatively, the doctor can prescribe a blood test to diagnose the Thyroid Stimulating Hormone levels in the body. Abnormal results for the same are indicative of iodine deficiency and may be followed up with an ultrasound to check the condition of the thyroid gland.
Babies in Australia undergo a heel prick test on a regular basis that is performed in order to detect low levels of thyroid hormone. This is said to be a way of picking up on low TSH which can be indicative of iodine deficiency or a result of some other health issues.(27,28,29)
Treatment of Iodine Deficiency:
Patients with iodine deficiency are referred to endocrinologists for proper treatment. Endocrinologists are doctors that specialize in dealing with hormonal imbalance and the health concerns that arise because of it.
The common way of treating iodine deficiency is the consumption of iodine-rich food. This can be done either using iodine-rich or iodised salt in food preparation or by using iodine supplements to combat its low levels. Alternatively, using iodised oil is also a way of dealing with low iodine levels. This is administered either orally or intramuscularly. From all these, using iodised salt is the best and the most affordable means of treatment.
In case of patients with hypothyroidism, the treatment includes consumption of synthetically produced thyroid hormone in the form of a pill. This needs to be taken on a regular basis and the treatment lasts for the patient’s lifetime.
Consuming an excess amount of iodine in the form of iodine supplements can cause similar problems as one has to face while having iodine deficiency, for example, goitre. When the level of iodine is quite high, the symptoms one experience differs for each individual and mainly it depends on the health condition of the person.
Before taking supplements to increase iodine content in the diet, one should consult the doctor or an accredited dietician.(24,25,30)
Iodine is a really important nutrient we all need. Especially A pregnant woman requires more iodine than usual for the healthy development of the baby. Additionally, a severe iodine deficiency can also result in stillbirth in some cases. If any woman is already suffering from thyroid issues, she should avoid taking iodine supplements without consulting with her doctor. Consuming too much iodine can have negative effects on the body. So you should include it in the recommended amount in the diet so you don’t suffer from iodine deficiency.