The fact that the lack of a certain substance, as it turned out later, iodine, causes a disease, later called a base disease, was written back in the Indian Vedas, in the Old Testament, in ancient Chinese books … They even knew how to treat it, since they gave the sick ash of burnt sea sponges, which contains iodine. But the element itself was accidentally discovered only in 1811 by Courtois, when, at the direction of Napoleon, he was looking for new sources of raw materials among marine plants. It was only in 1896 that Bauman discovered iodine in the thyroid gland and confirmed the fact that there is too little iodine in the case of a basic disease. In 1914, Kendal isolated thyrotoxin from the thyroid gland, the chemical formula of which was derived twelve years later, and then it was first synthesized1. And in 1917, the case of the death of thousands of pigs in the state of Montana in the United States alone due to a lack of iodine became widely known. After all, not only people, but also animals get sick with a “thyroid gland”: dogs, sheep, horses, pigs, cattle, rabbits, fish.

Soon they began to iodize table salt in those areas where this element was not enough. It was also proposed to include marine fish in the diet, in which there is a lot of iodine, and to exclude plants containing substances that contribute to the development of a base disease.  

Why is too little iodine in some areas? The fact is that its compounds are easily soluble in water, and in the mountains or in rocky areas they are simply washed away by rains and streams of water.

Japan has relatively little iodine in water, in the air, and in the soil, but the locals eat a lot of fish and “seafood,” rich in this element. In Taiwan, on the contrary, “seafood” is not traditionally eaten, and a common disease there is common, even iodization of drinking water does not help.   

In Poland, a lack of iodine was once very much felt in the south, in Subcarpathia. In 1932, for example, it was discovered that 15.5% of the recruits from the former Krakow Voivodeship had a Bazedov disease, and in western voivodships, only 0.1% of the recruits were unhealthy due to lack of iodine.

In 1930, salt was iodized in Subcarpathia, and by 1938 only 2.9% of recruits had been diagnosed with bazedova disease. During the war, salt was no longer iodized, and almost endemic disease broke out again (in 1946, 37% of the population was ill in two districts). Three years later, there were already half the number of patients, although salt was not always correctly iodized. We must not forget that children of women with bazedovy disease often have developmental delays, cretinism, dwarfs, etc. “. The lack of this element, in addition to the basic disease or mental retardation, can also cause changes in the chromosomes and contribute to the appearance of cancer.    

As it turned out, the spread of bazedovy disease depends not only on the lack of iodine in the soil and vegetation, but also on the lack of cobalt. In 1961, scientists Kolomintsev and Gabovich examined the population of the Gorno-Altai Territory. They concluded that excess cobalt also acts on the thyroid gland. If there is too much cobalt, the iodine content in the blood decreases.

The amount of iodine in plants depends not only on the content of this element in the soil, but also on the ability of the species to concentrate it. Some plants contain certain substances that cause bazedovy disease. This was discovered by Chesney back in 1928. Experimental rabbits were fed with cabbage leaves, and they showed signs of this disease. When they began to give iodine, the metabolism was adjusted, and other symptoms of malfunctioning of the thyroid gland disappeared. Further studies revealed nitrites and nitrates, which can turn into nitrosamines, in some vegetables (cruciferous family). Acetate derivatives of nitrosamines and cause an enlargement of the thyroid gland. It also turned out that excessive consumption of soybeans causes an increase in the thyroid gland (sometimes fivefold), increases the need for iodine by 100%. Later it turned out that there are many different compounds that have a similar effect, for example, some sulfa drugs, including the popular sulfoguanidine in Poland (a remedy for indigestion, already discontinued). All these factors causing bazedovy disease the stronger the effect, the less iodine in the environment and food.