Many people are deeply convinced that of all the existing useful trace elements, iodine occupies the last place in importance and it is possible to do without it. At least, few of us think about how to control the level of iodine in the body. And the prevention of deficiency is carried out by units at all. In fact, we are talking about a fateful substance that is not synthesized in our body. In adults, even a slight lack of it can lead to asymptomatic disorders of the thyroid gland, and in children — inhibit intellectual development. To stay healthy, we must receive iodine from the outside, and every day.
The iodine content in food products — milk, eggs, meat, cereals, fruits and vegetables — depends on the level of this trace element in the soil on which plants and animals were grown.
The problem acquired a planetary scale hundreds of thousands of years ago. The absence of iodine in the upper fertile layers of the soil (and hence in plants grown in depleted fields, and in the meat of animals that feed on these plants) is a natural phenomenon that humanity has to put up with. As a result of the long and turbulent geological life of the Earth, almost all the iodine that was on the surface of the land was washed away by rains and meltwater into the depths of the sea. Today, it is pointless to look for iodine in vegetables, fruits and nuts: there is negligible amount of it there. The only available source of trace element is the world ocean, more precisely, its edible gifts, which is why of all nations, only the Japanese, who consume fish, seafood and algae in large portions every day, are reliably insured against iodine deficiency.
What causes iodine deficiency in the body
Without iodine, synthesis of the two main thyroid hormones — thyroxine and triiodothyronine – is impossible. Both substances are necessary for the proper functioning of all organs and systems of the body. Lack of iodine initially leads to malfunctions in the thyroid gland, which, in the absence of proper treatment, are usually followed by disorders of the cardiovascular, nervous and reproductive systems, as well as problems with bone tissue, basic metabolism, and so on. An overabundance of trace elements is extremely rare, but also leads to unpleasant consequences (increased blood pressure, osteoporosis). The relationship between the state of the thyroid gland and other organs and tissues is explained by the fact that they all have special receptors sensitive to thyroxine and triiodothyranin. For this very reason, the lack of iodine never goes away without a trace.
In toddlers, iodine deficiency most often leads to diffuse endemic goiter — an increase in the thyroid gland (in adults, goiter is usually nodular or multi-nodular). With this disease, the organ increases in size in order to still produce the right amount of hormones in conditions of deficiency. Visually, these changes are not always noticeable, and in young children, goiter most often becomes a random find: as a rule, it is detected by a doctor during a routine examination. If the iodine deficiency is mild or moderate, then the function of the thyroid gland is usually preserved, and it is quite easy to correct the situation. Usually doctors prescribe a six-month course of iodine monopreparations in physiological doses (about 200 mcg), after which it is necessary to undergo a second examination. In severe forms, thyroid hormone preparations may be required.
Before making a diagnosis of «diffuse endemic goiter», the doctor should rule out autoimmune diseases. To do this, the baby needs to take a blood test for specific antibodies and do an ultrasound of the thyroid gland. Only after these two studies can we come to the right conclusion.
In regions with severe iodine deficiency, hypothyroidism may develop — a disease in which the synthesis of thyroid hormones is disrupted. In regions with moderate or mild deficiency, hypothyroidism can begin only against the background of chronic autoimmune thyroiditis, another serious disease unrelated to iodine deficiency. It is necessary to start the fight against hypothyroidism immediately: its consequences cannot be reversed. There is no need to be afraid of hormone therapy: drugs help to make up for the lack of hormone, which is vital for the baby.
Risk group for iodine deficiency
The risk group for the development of iodine deficiency diseases includes pregnant and lactating women and babies younger than 3 years. During pregnancy, the expectant mother has to share iodine reserves with the child, so during this period, thyroid disorders are observed quite often (endemic goiter occurs in 25% of pregnant women).
The need for iodine arises in the baby long before birth. Thyroxine and tri-iodothyronine take a direct part in the processes of growth and formation of the central nervous system, including the brain (its laying begins at the 16th-17th week). The fetus’s own thyroid gland does not develop immediately, so he needs the support of his mother. In order for the baby to receive the necessary portion of hormones, the required amount of iodine must enter the woman’s body. If at these terms the mother is experiencing a shortage, troubles are provided for the crumbs. Brain structures continue to be actively formed until the age of 3, and all this time the need for iodine in children remains high.
With a slight shortage, «borderline» intellectual development disorders usually develop. They cannot be detected with the help of medical research and laboratory tests, but it is quite easy to calculate them by indirect signs. Such children study much worse at school than their peers (it is especially difficult for them to learn exact sciences, which assume developed abstract thinking), do not shine with talents, their memory does not work well, they are inattentive and inquisitive. The most unpleasant thing is that all these side effects are irreversible, and it is impossible to fix them with medicines. With a pronounced shortage, there is a real threat of cretinism.
Known misconceptions about iodine and salt
1) Iodine deficiency is easy to notice
Pronounced symptoms (for example, endemic goiter) do not appear immediately, but only at a critical moment, before which the body experiences a shortage of iodine for quite a long time.
2) Sea salt makes up for the lack of iodine better than iodized
This is a myth. 1 g of iodized salt contains 40 mcg of iodine, and 1 g of sea salt contains only 1 mcg. Sea salt cannot be considered iodized, because iodine is present in it in scanty quantities. The way out is to buy iodized sea salt.
3) Iodized salt can cause overdose
For this to happen, it is necessary to consume almost 50 g of salt per day, which is impossible in principle: such dishes will be inedible.
4) Iodized salt is stored for a short time
Until the late 1990s, manufacturers used potassium iodide, a really not very stable iodine compound. According to the GOST adopted in 2000, today a more stable analogue, potassium iodate, is used for the same purposes. Thanks to technological know-how, the useful element has ceased to break down in the light, and the salt enriched with it no longer requires dark packaging. The shelf life of the «improved» version is at least 12 months.
