Editing Congenital iodine deficiency syndrome (section)

==History==
[[File:Cretinnen aus Steiermark, 1819 gez. Loder, gest. Leopold Müller.jpg|thumb|upright=1.4|Cretinism ([[Styria]]), copper engraving, 1815]]

A [[Goitre|goiter]] is the most specific clinical marker of either the direct or indirect insufficient intake of iodine in the human body. There is evidence of goiter, and its medical treatment with iodine-rich algae and burnt sponges, in Chinese, Egyptian, and Roman ancient medical texts. In 1848, King [[Charles Albert of Sardinia|Carlo Alberto]] of [[Sardinia]] commissioned the first epidemiological study of congenital iodine deficiency syndrome, in northern [[Savoy]] where it was frequent. In past centuries, the well reported social diseases prevalent among the poorer social classes and farmers, caused by dietary and agricultural monocultures, were: [[pellagra]], [[rickets]], [[beriberi]], [[scurvy]] in long-term sailors, and the [[endemic goiter]] caused by iodine deficiency. However, this disease was less mentioned in medical books because it was erroneously considered to be an aesthetic rather than a clinical disorder.<ref>{{cite journal |author=Venturi, Sebastiano |title=Iodine Deficiency in the Population of Montefeltro, A Territory in Central Italy Inside the Regions of Emilia-Romagna, Tuscany and Marche |journal=International Journal of Anthropology |volume=29 |issue=1–2 |pages=1–12 |year=2014 |url=http://www.pontecorboli.com/digital1/inte-journal-of-anthropology-archive/ |access-date=2015-11-02 |archive-url=https://web.archive.org/web/20160304063248/http://www.pontecorboli.com/digital1/inte-journal-of-anthropology-archive/ |archive-date=2016-03-04 |url-status=dead }}</ref>

Congenital iodine-deficiency syndrome was especially common in areas of southern Europe around the Alps and was often described by ancient Roman writers and depicted by artists. The earliest Alpine mountain climbers sometimes came upon whole villages affected by it.<ref>Fergus Fleming, ''Killing Dragons: The Conquest of the Alps'', 2000, Grove Press, p. 179</ref> The prevalence of the condition was described from a medical perspective by several travellers and physicians in the late 18th and early 19th centuries.<ref>See, for example, [[William Coxe (historian)|William Coxe]], "Account of the [[Valais|Vallais]], and of the Goiters and Idiots of that Country," ''Universal Magazine of Knowledge & Pleasure'', vol. 67, Dec. 2, 1780.</ref>  At that time the cause was not known and it was often attributed to "stagnant air" in mountain valleys or "bad water". The proportion of people affected varied markedly throughout southern Europe and even within very small areas; it might be common in one valley and not another. The number of severely affected persons was always a minority, and most persons were only affected to the extent of having a goitre and some degree of reduced cognition and growth. The majority of such cases were still socially functional in their pastoral villages.<ref>{{Cite journal |last1=Weichenberger |first1=Christian X. |last2=Rivera |first2=Maria Teresa |last3=Vanderpas |first3=Jean |date=2020-10-02 |title=Familial Aggregation of Endemic Congenital Hypothyroidism Syndrome in Congo (DR): Historical Data |journal=Nutrients |volume=12 |issue=10 |pages=3021 |doi=10.3390/nu12103021 |issn=2072-6643 |pmc=7601371 |pmid=33023116|doi-access=free }}</ref>

More mildly affected areas of Europe and North America in the 19th century were referred to as "goitre belts". The degree of iodine deficiency was milder and manifested primarily as thyroid enlargement rather than severe mental and physical impairment. In Switzerland, for example, where soil does not contain a large amount of iodine, cases of congenital iodine deficiency syndrome were very abundant and even considered genetically caused. As the variety of food sources dramatically increased in Europe and North America and the populations became less completely dependent on locally grown food, the prevalence of endemic goitre diminished. This is supported by a 1979 WHO publication which concluded that "changes in the origin of food supplies may account for the otherwise unexplained disappearance of endemic goitre from a number of localities during the past 50 years".<ref>{{Cite book|last=De Maeyer, Lowenstein, Thilly|title=The Control of Endemic Goitre|publisher=WORLD HEALTH ORGANIZATION|year=1979|isbn=92-4-156060-6|location=Geneva, Switzerland|pages=9–10}}</ref>

The early 20th century saw the discovery of the relationships of neurological impairment with hypothyroidism due to iodine deficiency. Both have been largely eliminated in the developed world.<ref>{{cite web |url=https://www.lecturio.com/concepts/hypothyroidism/| title=Hypothyroidism|website=The Lecturio Medical Concept Library |access-date= 27 July 2021}}</ref>