Question to an expert: Does everyone need iodized salt?
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Iodized salt can be bought in any store for a long time, and in 2020, a bill developed by the Ministry of Health on the mandatory iodization of salt should come into force – then it will be used for the preparation of industrial food products, in particular bread. The purpose of the law is to prevent iodine deficiency. But does everyone really need iodized salt? Are there people for whom iodine is contraindicated, and what should they do in conditions of total iodization? We asked these questions to an expert.
For humans, iodine is a vital microelement; without it, the normal functioning of the body is impossible. Depending on age and state of health, you need from 100 to 250 micrograms of this substance per day. Iodine is a constituent of thyroid hormones, which perform many functions in people of all ages, and especially during intrauterine development and infancy. The main thing that these hormones do is to regulate metabolic processes in all tissues.
Thyroid hormones are very important for the maturation of the brain and the formation of intelligence, and their deficiency can result in a deterioration in intellectual and motor functions. The most difficult consequence of iodine deficiency during the mother’s pregnancy is the so-called endemic cretinism, that is, an extreme degree of mental and physical development retardation; other risks are miscarriage and stillbirth. In adults, manifestations of iodine deficiency include goiter (an enlarged thyroid gland) and sometimes hypothyroidism (insufficient thyroid hormone).
The method of mass prevention of iodine deficiency was formulated more than a hundred years ago, and it consists in the iodization of salt. The fact is that salt is available, cheap, we use it in small quantities. The daily requirement for iodine is small, so there is a risk of overdose – but this is excluded when using iodized salt. If a person eats the recommended 5 grams of salt per day, then the body receives 100-200 micrograms of iodine – just a physiological norm.
A particularly vulnerable group includes pregnant and breastfeeding women, as well as children under two years of age; they are given additional prophylaxis. Preparations containing potassium iodide are prescribed 250 mcg per day during pregnancy planning, its entire course and breastfeeding. Children who do not receive breast milk are recommended mixtures fortified with iodine – at least 90 mcg per liter of prepared liquid.
To avoid iodine deficiency in children and adults, in many countries (now there are ninety), mandatory salt iodization has been introduced . Somewhere, for example, in Poland or the Czech Republic, it only applies to table salt, which people use at home. In other countries, for example, in the Netherlands, Belarus, Denmark, Slovakia, Austria, salt iodization is total. There iodized salt is not only sold in stores – it is prepared with it in restaurants and cafes, it is used in food production. There is a myth that iodized salt reacts with foods, but this is not the case. Nowadays, potassium iodite is used to iodize salt: it is stable during storage and heating, so that modern enriched salt can be used even in baking. In countries with total salt iodization, the problem of iodine deficiency has been eliminated, with partial – practically eliminated.
There is no need to donate blood, urine, or hair for an iodine test, although such an analysis can technically be done. For example, epidemiologists have studied urinary iodine excretion to identify regions of iodine deficiency. Russia definitely belongs to such regions. Almost throughout the country there is a mild and moderate iodine deficiency, and with food, people receive three times less iodine than they need. So it is worth buying iodized salt without waiting for the law – especially since it is not known whether it will come into effect; it has been discussed since at least 2013 .
It is impossible to get an excess of iodine from food – there is a risk only when using medications containing it. In particular, 1 ml of alcoholic tincture of iodine contains 50 mg (this is 50,000 mcg) of iodine. Such a dose can lead to disruption of the thyroid gland. You should not be afraid of iodized salt – preventive doses of iodine will not even affect the course of thyroid diseases with excessive production of hormones.
They are also sometimes afraid of an allergy to iodized salt, but in vain – iodine is a trace element, and there can be no allergy to it by definition. Possible intolerance to iodine in doses of more than 1000-2000 micrograms, which cannot be obtained from iodized salt. The only contraindication to iodine intake in salt is the period of preparation for radioiodine therapy – a special method used to treat thyroid cancer after surgery. At this time, a special iodine-free diet is prescribed for two to four weeks – and then you need to give up not only salt, but also many other foods, and eat mainly fruits, vegetables, nuts and cereals.