Autoimmune disease: Pathogenesis, Genetics, Immunotherapy, Microbial triggers, Prophylaxis

In mountainous parts of the world, such as Switzerland, the Himalayas, the Andes and New Zealand, Goiter (an enlargement of the thyroid gland) is common. This was discovered to be due to shortage in the soil of the trace element iodine [1]. Surprisingly, Kelly et al. [2], London scientists recruited by the Chilean government discovered that iodine in soil does not come from the weathering of rock. Iodine is dissolved in the sea from which it vaporizes by oxidation to be deposited in soils by rain. From the soil, iodine is taken up by plants from where it comes to man, directly in vegetables and fruit or indirectly through meat animals. Iodine takes a long time to build up in soils to the levels we need for manufacture of sufficient thyroid hormone. Geologically old soils, like those of England and France and the Eastern United States, contain adequate iodine for human need but the new soils of Switzerland, the Himalayas, Chile and New Zealand, where there has been geologically recent up-thrust of mountains have not had time to accumulate adequate amounts of iodine to meet the needs for humans and other animals. This causes goitre, an enlargement of the thyroid gland, caused by increased secretion of thyroid stimulating hormone from the pituitary gland aimed at enabling an enlarged thyroid to obtain more iodine from the blood. In New Zealand, HD Purves [3], with brilliant studies, found that the amount of iodine needed to be added to the domestic salt was 1 part of potassium iodide per 20,000 parts of sodium chloride, 10 times more than the ineffectual level previously used. This abolished New Zealand’s endemic goitre [4].