When was iodine added to salt

When back in Bernard Courtois noticed the violet fumes produced when his seaweed extraction tank was being cleaned, he could have never dreamed that he had set the stage for one of the most important nutritional interventions in history. Courtois owned a factory that produced potassium nitrate, better known as saltpetre.

This substance was a major component of gunpowder and was in great demand by the military. One source of potassium nitrate was vegetable matter and Courtois had found that decaying seaweed fit the bill nicely.

But the large tanks used to extract the seaweed had to be periodically cleaned, a difficult procedure that required the use of acids. When one day a particularly large amount of acid was used, violet fumes appeared and condensed on the cold surfaces of the tank into dark metallic-looking crystals.

This review highlights the history of the discovery of iodine and its uses, discusses the sources of iodine nutrition, and summarizes the current recommendations for iodine intake with a focus on women of childbearing age.

Adequate levels of iodine, a trace element variably distributed on the earth and found mostly in the soil and water of coastal areas, are required for the synthesis of the thyroid hormones, thyroxine T4 and triiodothyronine T3 , which play key roles in the metabolic processes of vertebrate life.

The major concerns regarding the global burden of iodine deficiency are related to goiter, neurocognitive impairments, and in severe deficiency, hypothyroidism resulting in cretinism. Early Chinese medical writings in approximately B. Although iodine was yet to be discovered, these remedies remained effective and their use continued globally, as was documented in writings by Hippocrates, Galen, Roger, and Arnold of Villanova in later centuries [ 1 ].

The discovery of iodine was made incidentally during the early part of the 19th century. In , while extracting sodium salts necessary for the manufacture of gunpowder, Bernard Courtois, a French chemist, observed an unusual purple vapor arising from seaweed ash treated with sulphuric acid [ 1 ].

In , the first paper presenting the new element, iodine termed after the Greek word, ioeides , translated as violet-colored , by Gay-Lussac was read [ 1 ]. Shortly following this, J. In , Adolphe Chatin, a French chemist, was the first to publish the hypothesis of population iodine deficiency associated with endemic goiter [ 3 ]. This was confirmed by Eugen Baumann, who, in , reported the discovery of iodine within the thyroid gland [ 4 ].

Iodine atomic weight The effects of glaciation, flooding, and leaching into soil during the Ice Age have led to the variable geographic distribution of iodine. As a result of these natural forces, iodine accumulation is found mostly in coastal areas, and the most common sources of dietary iodine are seaweed and other seafood. The fortification of salt with iodine is an effective, inexpensive, and stable route of ensuring adequate iodine intake. The stability of iodine in salt may depend on various environmental and storage conditions [ 5 ].

In some regions of the world where salt iodization is impractical, iodization of other common foods bread and others is targeted, or individuals receive administered oral or intramuscular iodized oil supplements. Other sources of intermittent iodine exposure may include the use of iodine-rich medications such as amiodarone and iodine-enriched cough medications , topical antiseptics, iodine-containing multivitamins and supplements, radiographic contrast agents, and water purification tablets.

In the U. Seafood is another excellent source of dietary iodine. The Total Diet Study by the U. Food and Drug Administration FDA in — reported that the important sources of dietary iodine were dairy and grain products [ 7 ], as was confirmed by a recent survey of these foods in the Boston area [ 8 ].

The iodine content of plant foods depends on the iodine levels in soil and in groundwater used in irrigation, in crop fertilizers, and in livestock feed. The results of early studies were the basis for advocating iodine supplementation to decrease goiter.

In the s, the French nutritional chemist, Jean Baptiste Boussingault, observed that the prevalence of goiter was increased in areas where naturally-occurring iodized salt was infrequently consumed and recommended the distribution of naturally iodized salt for public consumption [ 2 ].

However, although there were attempts to implement iodine prophylaxis in the U. Iodine supplementation, primarily through the fortification of table salt, did not begin until the early s and occurred initially in Switzerland and the U. Prior to the s, endemic iodine deficiency was prevalent in the Great Lakes, Appalachians, and Northwestern regions of the U. Selective Service regulations [ 12 ]. Subsequent surveillance studies in the following year by Levin and R.

Olin, Commissioner of the Michigan State Department of Public Health, demonstrated that the prevalence of goiter reached as high as David Marine, a U.

Over the next few years, he and colleagues published a series of papers reporting a significantly decreased frequency of goiter in children treated with iodine 0. His work with the Society over the next few years, through the development of the Iodized Salt Committee, was instrumental in the history of the U.

The region had largely been severely iodine deficient, and Hartsock in described an outbreak of thyrotoxicosis in adults who took iodized salt living in the Great Lakes region of the goiter belt [ 15 ]. Dasgupta, Yining Liu, Jason V. Iodine nutrition: iodine content of iodized salt in the United States. Like this: Like Loading Published by dreddymd. Eddy Bettermann MD. Pingback: What Is Iodine?

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Post was not sent - check your email addresses! Over a billion people are at risk of iodine deficiency today in the developing world, especially in formerly glaciated or mountainous areas, leading to cretinism stunted mental and physical growth with hypothyroidism.

Although iodized salt has prevented this problem in the developed world, it is still not provided in many areas where it would be cost-effective. After the US resumed conscription in World War I, many recruits were deemed ineligible because of goiter and associated problems.

This is what led to the Progressive mandate for iodized salt. Some tests on fish with goiter were conducted but no large randomized controlled studies done before iodine was added. It seems that there was an excess of deaths in the next some years because the added iodine promoted hyperthyroidism in some, leading to thyrotoxicosis and heart attacks.

Today thyroid problems are more easily diagnosed to avoid such complications, and randomized controlled studies required first. Recommendations to attempt to lower blood pressure by reducing sodium intake have probably led to lower iodine intake in some, maybe resulting in excess subclinical hypothyroidism. Morton salt adds manmade Iodide, as opposed to Iodine.

I am torn on whether I should discontinue buying salt with Iodide now. Adult men and women should have approximately micrograms of iodine each day, and most people in the United States easily obtain this much through their diet, says the National Institutes of Health.

By contrast, potassium iodide is a man-made salt compound of iodine. The Centers for Disease Control and Prevention cautions that you should not take potassium iodide unless you have been instructed to do so by your doctor. Elemental iodine cannot be found in nature. So I owe a bit of apology here. Well as coincidence has it, I came across this after one last look.