Iodised salt - wikipedia Iodised salt Global logo for iodised salt. Logos, such as this one, are placed on salt packages to help consumers identify salt that contains added iodine. Iodised salt ( also spelled iodized salt ) is table salt mixed with a minute amount of various salts of the element iodine. The ingestion of iodine prevents iodine deficiency. Worldwide, iodine deficiency affects about two billion people and is the leading preventable cause of intellectual and developmental disabilities. Deficiency also causes thyroid gland problems, including `` endemic goitre ''. In many countries, iodine deficiency is a major public health problem that can be cheaply addressed by purposely adding small amounts of iodine to the sodium chloride salt. Iodine is a micronutrient and dietary mineral that is naturally present in the food supply in some regions, especially near sea coasts, but is generally quite rare in the Earth 's crust, since iodine is a so - called `` heavy '' element and abundance of chemical elements generally declines with greater atomic mass. Where natural levels of iodine in the soil are low and the iodine is not taken up by vegetables, iodine added to salt provides the small but essential amount of iodine needed by humans. An opened package of table salt with iodide may rapidly lose its iodine content through the process of oxidation and iodine sublimation. Contents 1 Chemistry, biochemistry and nutritional aspects 2 Production 3 In public health initiatives 3.1 Argentina 3.2 Australia 3.3 Brazil 3.4 Canada 3.5 China 3.6 Kazakhstan 3.7 Philippines 3.8 Romania 3.9 South Africa 3.10 United States 4 No - additive salts for canning and pickling 5 Fortification of salt with other elements 5.1 Double - fortified salt 5.2 Fluoridated salt 5.3 Diethylcarbamazine 6 See also 7 Notes 8 References 9 External links Chemistry, biochemistry and nutritional aspects A pile of iodised salt. Four inorganic compounds are used as iodide sources, depending on the producer : potassium iodate, potassium iodide, sodium iodate, and sodium iodide. Any of these compounds supplies the body with its iodine required for the biosynthesis of thyroxine ( T ) and triiodothyronine ( T ) hormones by the thyroid gland. Animals also benefit from iodine supplements, and the hydrogen iodide derivative of ethylenediamine is the main supplement to livestock feed. Salt is an effective vehicle for distributing iodine to the public because it does not spoil and is consumed in more predictable amounts than most other commodities. For example, the concentration of iodine in salt has gradually increased in Switzerland : 3.75 mg / kg in 1952, 7.5 mg / kg in 1962, 15 mg / kg in 1980, 20 mg / kg in 1998, and 25 mg / kg in 2014. These increases were found to improve iodine status in the general Swiss population. Salt that is iodised with iodide may slowly lose its iodine content by exposure to excess air over long periods. Production Edible salt can be iodised by spraying it with a potassium iodate or potassium iodide solution. 57 grams of potassium iodate, costing about US $1.15 ( in 2006 ), is required to iodise a ton of salt. Dextrose is added as a stabilizer to prevent potassium iodide from oxidizing and evaporating. Anti-caking agents such as calcium silicate are commonly added to table salt to prevent clumping. In public health initiatives Iodised salt with folic acid and fluorine. The folic acid gives a light yellow colour to the salt. Worldwide, iodine deficiency affects two billion people and is the leading preventable cause of intellectual and developmental disabilities. According to public health experts, iodisation of salt may be the world 's simplest and most cost - effective measure available to improve health, only costing US $0.05 per person per year. At the World Summit for Children in 1990, a goal was set to eliminate iodine deficiency by 2000. At that time, 25 % of households consumed iodised salt, a proportion that increased to 66 % by 2006. Salt producers are often, although not always, supportive of government initiatives to iodise edible salt supplies. Opposition to iodisation comes from small salt producers who are concerned about the added expense, private makers of iodine pills, concerns about promoting salt intake, and unfounded rumours that iodisation causes AIDS or other illnesses. The United States Food and Drug Administration recommends 150 micrograms ( 0.15 mg ) of iodine per day for both men and women. Argentina Since 8 May 1967 salt for human or animal use must be iodised, according to the Law 17,259. Australia Australian children were identified as being iodine deficient in a survey conducted between 2003 and 2004 As a result of this study the Australian Government mandated that all bread with the exception of `` organic '' bread must use iodized salt. There remains concern that this initiative is not sufficient for pregnant and lactating women. Brazil Iodine Deficiency Disorders were detected as a major public health issue by Brazilian authorities in the 1950s, when about 20 % of the population had goiter. The National Agency for Sanitary Vigilance ( ANVISA ) is responsible for setting the mandatory iodine content of table salt. The Brazilian diet averages 12 g of table salt per day, more than twice the recommended value of 5 ga day. To avoid excess consumption of iodine, the iodizing of Brazilian table salt was reduced to 15 -- 45 mg / kg in July 2013. Specialists criticized the move, saying that it would be better for the government to promote reduced salt intake, which would solve the iodine problem as well as reduce the incidence of high blood pressure. Canada Salt sold to consumers in Canada for table and household use must be iodized with 0.01 % potassium iodide. Sea salt and salt sold for other purposes, such as pickling, may be sold uniodized. China Much of the Chinese population lives inland, far from sources of dietary iodine. In 1996, the Ministry of Public Health estimated that iodine deficiency was responsible for 10 million cases of mental retardation in China. The Chinese government had held a legal monopoly on salt production since 119 BCE and began iodizing salt in the 1960s, but market reforms in the 1980s led to widespread smuggling of non-iodized salt from private producers. In the inland province of Ningxia, only 20 % of salt consumed was sold by the China National Salt Industry Corporation. The Chinese government responded by cracking down on smuggled salt, establishing a salt police with 25,000 officers to enforce the salt monopoly. Consumption of iodized salt reached 90 % of the Chinese population by 2000. Kazakhstan Kazakhstan, a country in Central Eurasia in which local food supplies seldom contain sufficient iodine, has drastically reduced iodine deficiency through salt iodisation programmes. Campaigns by the government and non-profit organisations to educate the public about the benefits of iodised salt began in the mid 1990s, with iodisation of edible salt becoming legally mandatory in 2002. Philippines On December 20, 1995, Philippine President Fidel V. Ramos signed Republic Act 8172 : An Act for Salt Iodization Nationwide ( ASIN ). Romania According to the 568 / 2002 law signed by the Romanian parliament and republished in 2009, since 2002 iodised salt is distributed mandatory in the whole country. It is used mandatory on the market for household consumption, in bakeries and for pregnant women. Iodised salt is optional though for animal consumption and the food industry, although widely used. The salt iodisation process has to assure a minimum of 30mg iodine / kg of salt. South africa The South African government instructed that all salt for sale was to be iodised after December 12, 1995. United States In the U.S. in the early 20th century, goitre was especially prevalent in the region around the Great Lakes and the Pacific Northwest. David Murray Cowie, a professor of paediatrics at the University of Michigan, led the U.S. to adopt the Swiss practice of adding sodium iodide or potassium iodide to table and cooking salt. On May 1, 1924, iodised salt was sold commercially in Michigan. By the fall of 1924, Morton Salt Company began distributing iodised salt nationally. There was a gradual increase in average intelligence of 1 standard deviation, 15 points, in iodine - deficient areas and 3.5 points nationally. A 2017 study found that the introduction of iodized salt in 1924 raised the IQ for the one - quarter of the population most deficient in iodine. These findings `` can explain roughly one decade 's worth of the upward trend in IQ in the United States ( the Flynn effect ). '' The study also found `` a large increase in thyroid - related deaths following the countrywide adoption of iodized salt, which affected mostly older individuals in localities with high prevalence of iodine deficiency. '' No - additive salts for canning and pickling In contrast to table salt, which often has iodide as well as anticaking ingredients, special canning and pickling salt is made for producing the brine to be used in pickling vegetables and other foodstuffs. This salt has no iodine added because the iodide can be oxidised by the foods and darken them -- a harmless but aesthetically undesirable effect. Fortification of salt with other elements Double - fortified salt Salt can also be double - fortified with iron and iodine. The iron is microencapsulated with stearin to prevent it from reacting with the iodine in the salt. By providing iron in addition to iodine in the convenient delivery vehicle of salt, it could serve as a sustainable approach to combating both iodine and iron deficiency disorders in areas where both deficiencies are prevalent. Adding iron to iodised salt is complicated by a number of chemical, technical, and organoleptic issues. Since a viable DFS premix became available for scale - up in 2001, a body of scientific literature has been emerging to support the DFS initiative including studies conducted in Ghana, India, Côte d'Ivoire, Kenya and Morocco. Fluoridated salt In some countries, table salt is treated with potassium fluoride to enhance dental health. Diethylcarbamazine In India and China, diethylcarbamazine has been added to salt to combat lymphatic filariasis. See also Basil Hetzel Enriched flour serves an analogous function to `` enriched salt ''. History of salt Lugol 's iodine Sea salt Water fluoridation, a similar public health intervention Notes ^ Jump up to : McNeil, Donald G. Jr ( 2006 - 12 - 16 ). `` In Raising the World 's I.Q., the Secret 's in the Salt ''. New York Times. Retrieved 2008 - 12 - 04. ^ Jump up to : `` Iodine deficiency -- way to go yet ''. The Lancet. 372 : 88. 12 July 2008. PMID 18620930. doi : 10.1016 / S0140 - 6736 ( 08 ) 61009 - 0. Retrieved 2014 - 12 - 10. Jump up ^ Diosady, L.L., and M.G. Venkatesh Mannar. `` Stability of iodine in iodized salt. '' 8th World Salt Symposium. Amsterdam : Elsevier. 2000. Jump up ^ Phyllis A. Lyday `` Iodine and Iodine Compounds '' in Ullmann 's Encyclopedia of Industrial Chemistry, Wiley - VCH, Weinheim, 2005. doi : 10.1002 / 14356007. a14_381 Jump up ^ `` Sel de cuisine : hausse du taux d'enrichissement en iode '' ( in French ). Swiss Federal Administration. Retrieved 8 January 2014. Jump up ^ Michael B Zimmermann ; Isabelle Aeberli ; Toni Torresani ; Hans Bürgi ( August 2005 ). `` Increasing the iodine concentration in the Swiss iodized salt program markedly improved iodine status in pregnant women and children : a 5 - y prospective national study ''. American Journal of Nutrition. 82 ( 2 ) : 388 -- 392. PMID 16087983. Jump up ^ Katarzyna Waszkowiak & Krystyna Szymandera - Buszka. Effect of storage conditions on potassium iodide stability in iodized table salt and collagen preparations. International Journal of Food Science & Technology. Volume 43 Issue 5, Pages 895 - 899. ( Published Online : 27 Nov 2007 ) Jump up ^ `` Iodized Salt ''. The Salt Institute. Retrieved 7 October 2013. Jump up ^ 2005 CFR Title 21, Volume 2 Jump up ^ Ley 17.259 Jump up ^ Li, Mu ; Eastman, Creswell J. ; Waite, Kay V. ; Ma, Gary ; Byth, Karen ; Zacharin, Margaret R. ; Topliss, Duncan J. ; Harding, Philip E. ; Walsh, John P. ( 2006 - 01 - 01 ). `` Are Australian children iodine deficient ? Results of the Australian National Iodine Nutrition Study ''. Medical Journal of Australia. 184 ( 4 ). ISSN 0025 - 729X. Jump up ^ Corporation, Australian Broadcasting. `` Your daily bread, now with iodine - Health & Wellbeing ''. www.abc.net.au. Retrieved 2016 - 12 - 31. Jump up ^ Gallego, Gisselle ; Goodall, Stephen ; Eastman, Creswell J. ( 2010 - 01 - 01 ). `` Iodine deficiency in Australia : is iodine supplementation for pregnant and lactating women warranted ? ''. Medical Journal of Australia. 192 ( 8 ). ISSN 0025 - 729X. Jump up ^ ( in Portuguese ) Research assesses impact of iodised salt in Brazil Jump up ^ Salt with less iodize should be mandatory in Brazil in up to 90 days -- Bem Estar -- Globo ( in Portuguese ) Jump up ^ `` Labelling Requirements for Salt ''. Jump up ^ Tyler, Patrick E. ( 4 June 1996 ). `` China Confronts Retardation Of Millions Deficient in Iodine ''. The New York Times. Retrieved 28 October 2015. Jump up ^ Fackler, Martin ( October 13, 2002 ). `` Special police protect an ancient monopoly -- and China 's public health ''. Associated Press. Jump up ^ http://www.gov.ph/1995/12/20/republic-act-no-8172/ Jump up ^ SUSTAINABLE PREVENTION OF IODINE DEFICIENCY AND ACHIEVEMENT OF OPTIMAL IODINE NUTRITION - ROMANIA http://www.ign.org/cm_data/Poster_Romania.pdf Jump up ^ DECISION no. 568 of 5 June 2002 ( republished ) http://legislatie.just.ro/Public/DetaliiDocument/36611 Jump up ^ Health Hints, Cerebos Archived March 25, 2008, at the Wayback Machine. Jump up ^ Impact after 1 year of compulsory iodisation on the iodine content of table salt at retailer level in South Africa, 1999, vol. 50, no. 1, pp. 7 -- 12 ( 12 ref. ), International journal of food sciences and nutrition ISSN 0963 - 7486 Jump up ^ Markel, When in Rains it Pours, p. 220 Jump up ^ McClure RD ( October 1935 ). `` GOITER PROPHYLAXIS WITH IODIZED SALT ''. Science. 82 ( 2129 ) : 370 -- 371. PMID 17796701. doi : 10.1126 / science. 82.2129. 370. Retrieved 2010 - 02 - 06. Jump up ^ Max Nisen ( July 22, 2013 ). `` How Adding Iodine To Salt Resulted In A Decade 's Worth Of IQ Gains For The United States ''. Business Insider. Retrieved July 23, 2013. ^ Jump up to : Feyrer, James ; Politi, Dimitra ; Weil, David N. ( 2017 ). `` The Cognitive Effects of Micronutrient Deficiency : Evidence from Salt Iodization in the United States ''. Journal of the European Economic Association. 15 ( 2 ) : 355 -- 387. Jump up ^ Smith, S.E. `` What Is Pickling Salt ? ''. wisegeek.com. Retrieved 5 October 2011. Jump up ^ Diosady LL and Mannar MGV. Double fortification of salt with iron and iodine., 2000, University of Toronto, Department of Chemical Engineering, The Pages of Professor L.L. Diosady Jump up ^ Andersson M, Thankachan P, Muthayya S, Goud RB, Kurpad AV, Hurrell RF, Zimmermann MB ( Nov 2008 ). `` Dual fortification of salt with iodine and iron : a randomized, double - blind, controlled trial of micronized ferric pyrophosphate and encapsulated ferrous fumarate in southern India ''. Am J Clin Nutr. 88 ( 5 ) : 1378 -- 87. Jump up ^ Double Fortification of Salt : a Technical Breakthrough to Alleviate Iron and Iodine Deficiency Disorders Around the World. The Micronutrient Initiative., Micronutrient Initiative. Jump up ^ Aigueperse, Jean ; Paul Mollard ; Didier Devilliers ; Marius Chemla ; Robert Faron ; Renée Romano ; Jean Pierre Cuer ( 2005 ). `` Fluorine Compounds, Inorganic ''. In Ullmann. Encyclopedia of Industrial Chemistry. Weinheim : Wiley - VCH. doi : 10.1002 / 14356007. a11_307. Jump up ^ ( 1 ) WHO : Unfulfilled potential : using diethylcarbamazine - fortified salt to eliminate lymphatic filariasis References Markel Howard ( 1987 ). `` When It Rains It Pours : Endemic Goiter, Iodized Salt, and David Murray Cowie MD ''. American Journal of Public Health. 77 ( 2 ) : 219 -- 229. PMC 1646845. PMID 3541654. doi : 10.2105 / AJPH. 77.2. 219. 21 CFR 101.9 ( c ) ( 8 ) ( iv ) Newton County -- Encyclopedia of Arkansas External links Network for Sustained Elimination of Iodine Deficiency Iodine intake as a risk factor for thyroid cancer : a comprehensive review of animal and human studies Salt History History of salt In the American Civil War International Salt Co. v. United States In Middlewich Old Salt Route In Chinese history Salt March Salt road Types Abraum Alaea Alberger Bittern Black lava Butter Celery Curing Cyclic Dairy Flake Fleur de sel Garlic Himalayan Iodised Kala namak Kosher ( Korean sea ) LoSalt Calcium chloride Pickling Potassium chloride Potassium nitrate Sodium nitrate Onion Rock Sea salt Seasoned Sel gris Smoked Truffle Food usage Brining Salting Brined cheese Salt - cured meat Salted fish Health effects Salt and cardiovascular disease Commerce and industry Salt Industry Commission Evaporation pond Production Salt mining Open - pan salt making List of countries by salt production By region In Cheshire In Ghana In Syracuse, New York Culture Salt in the Bible Salting the earth Miscellaneous Mineral lick Smelling salts Ximenes Redoubt Food portal Retrieved from `` https://en.wikipedia.org/w/index.php?title=Iodised_salt&oldid=806246718 '' Categories : Edible salt Iodine History of salt Endocrinology Hidden categories : CS1 French - language sources ( fr ) Articles with Portuguese - language external links Webarchive template wayback links All articles with unsourced statements Articles with unsourced statements from March 2012 Talk Contents About Wikipedia Čeština Deutsch Español فارسی Français 한국어 Bahasa Indonesia Nederlands Português Русский Simple English ไทย Українська Tiếng Việt 中文 Edit links This page was last edited on 20 October 2017, at 18 : 31. 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Question: when did they start putting iodine in salt
Answer: 1924