Iodine in salt
Notes from Internet by Henry Lahore Feb 2012

RDA is currently 77 micrograms of iodine or about 1 gram of iodized salt

http://en.wikipedia.org/wiki/Iodised_salt 

Edible salt can be iodised by spraying it with a potassium iodate solution. 60 ml of potassium iodate, costing about US$1.15 (in 2006), are required to iodise a ton of salt.[1] Salt is an effective vehicle for distributing iodine to the public because it does not spoil and is consumed by everyone in the population in fairly predictable amounts.[citation needed] For example, the concentration of iodine in salt has gradually increased in Switzerland: 3.75 mg/kg in 1975, 7.5 mg/kg in 1962, 15 mg/kg in 1980, and 20 mg/kg in 1998. These increases were found to improve iodine status in the general Swiss population.[3]

Salt that is iodised with iodide may slowly lose its iodine content by exposure to excess air over long periods. The halogen iodide, over time and exposure to excess oxygen and carbon dioxide, slowly oxidises to metal carbonate and elemental iodine, which then evaporates.[4]

Worldwide, iodine deficiency affects two billion people and is the leading preventable cause of mental retardation.[1] 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.[1]

(note 5 cents per person per year for Iodine, 13 cents per person per year for Vitamin D)

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.[1]

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.[1] Iodisation programmes are more likely to be successful in areas where most edible salt is produced by a small number of large companies, as opposed to hundreds of smaller companies.

The United States Food and Drug Administration recommends[5] 150 micrograms of iodine per day for both men and women.

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.[6] 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.[7] By the fall of 1924, Morton Salt Company began distributing iodised salt nationally.

Over 80 years since the first use of iodized salt. Still a fraction of the world does not iodize salt

Pauling
Acute toxicity

Acute iodine poisoning is rare and usually occurs only with doses of many grams. Symptoms of acute iodine poisoning include burning of the mouth, throat, and stomach; fever; nausea; vomiting; diarrhea; a weak pulse; and coma (6).

Iodine excess

It is rare for diets of natural foods to supply more than 2,000 mcg of iodine/day, and most diets supply less than 1,000 mcg of iodine/day. People living in the northern coastal regions of Japan, whose diets contain large amounts of seaweed, have been found to have iodine intakes ranging from 50,000 to 80,000 mcg (50-80 mg) of iodine/day (1).

30X 150 = 45,000 which is less than some diets in Japan

Govt viewpoint – is seems
The RDA for iodine is 150 mcg. Ingestion of up to 20 times the RDA has no known side effects. Side effects of 30 times the RDA may include mouth sores, metallic taste, swollen salivary glands, diarrhea, vomiting, headache, rash, and breathing difficulties. 

An iodine deficiency is characterized by an enlarged thyroid gland (goiter), low thyroid hormone level and hypothyroidism. Other symptoms of iodine deficiency and thyroid problems may include fatigue, dry skin, rise in blood fats, voice hoarseness, slow reflexes, and poor mental clarity.

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http://www.iccidd.org/pages/protecting-children/fortifying-salt/history-of-salt-iodization.php 

History of salt iodization

The ancient Greeks and others used iodine-rich seaweed to combat goiters, but it was not until 1821 that French nutritional chemist Jean Baptiste Boussingault discovered salt iodine-rich salts could be used to treat goiter, though he did not understand its preventive role.  At the same time, Swiss physican J.F. Coindet  successfully employed iodine therapy for goiter.  Thirty years later, another French scientist, A. Chatin hypothesized that iodine deficiency caused goiters, but an expert group of his country's Academy of Scientists rejected the claim and killed the idea for another half century. 

In the years 1907-1909, Dr. David Marine, a young doctor in Cleveland, OH, USA, began working explicitly on using iodine-fortified salt to prevent goiter.  An early Marine effort to conduct a large-scale trial of iodized salt in the Cleveland public schools was vetoed by another doctor who served as chairman of the school board.  That delayed the determined Dr. Marine until 1916 when he teamed with O.P. Kimball to convince the Akron, OH school board to conduct the experiment on elementary school girls (who had twice the incidence of goiter).  The experiment was completely successful.  The lead shifted to Michigan where, due to the strong leadership of Dr. David Murray Cowie of the University of Michigan and the Michigan State Medical Society, a symposium highlighted the work in Akron and similar work in Switzerland.  Dr. Cowie contacted Diamond Crystal Salt Company (now merged into Cargill Salt Company) and Morton Salt Company, leading to discussions with the salt producers association and by 1924 iodized salt was commonly available in the U.S.  In less than a decade, 90+% of the salt consumed in the U.S. "goiter belt" was iodized.  Goiter incidence plummeted, as an example, in Detroit from 9.7% to 1.4% in the first six years of using iodized salt.

David Marine later worked on salt iodization for the World Health Organization and many areas have replicated the benefits of iodized salt.

For further information:

Iodized Salt (Salt Institute)

"David Marine and the Problem of Goiter" by Kenneth J. Carpenter, Journal of Nutrition, 135;675-680 (2005)

"'When it Rains it Pours': Endemic Goiter, Iodized Salt, and David Murray Cowie, MD" by Howard Markel, MD, American Journal of Public Health 77;2:219-229 (1987)

"The History of Food Fortification in the United States: Its Relevance for Current Fortification Efforts in Developing Countries" by David Bishai and Ritu Nalubola, in Economic Development and Cultural Change (Chicago, University of Chicago Press, 2002)
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http://chemistry.about.com/b/2012/01/26/this-day-in-science-history-january-27-iodized-salt.htm 

Cowie was aware of a Swiss process of adding sodium iodide to table salt (sodium chloride) and managed to convince Michigan salt producers to include minute quantities of sodium iodide to their salt for consumption locally. This type of salt was identified by the label "contains .01 per cent sodium iodide". In less than a year, the Morton Salt Company was distributing iodized salt nationally.
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Salt fortification was called for after an experiment involving 5,000 Ohio schoolgirls using sodium iodide. The four year study showed an immediate decrease in goiter rate for those who previously had one, with no development of goiter in those who initially were goiter free. Half of the non-iodine controls developed goiter, proving the effectiveness of iodine supplementation in goiter prevention. In 1951, a follow-up study was completed in Michigan, showing that the introduction of iodized salt dropped the goiter rate from 38.6% to 1.4%.

The iodine content of U.S. and Canadian iodized salt is 100 ppm, or 77 µg iodine/g sodium chloride, while it is generally 20-40 ppm in other countries.

A majority of salt consumed in the U.S. comes from processed foods that do not typically use iodized salt.

New dietary guidelines for Americans now recommend a decrease in salt consumption from 2.3 to 1.5 g/day, potentially resulting in a decrease in iodine intake and an increase in people suffering from iodine deficiency.

http://www.endfatigue.com/health_articles_f-n_2/Iodine-deficiency_old_epidemic_is_back.html 

Until recently, about 25% of the iodine in the diet was from wheat, because iodine was used in the processing of flour. Now, however, a lot of flour in the U.S. is processed with a chemical cousin of iodine, bromide (potassium bromate), which helps makes flour doughier, rise higher, and gives the loaf a better appearance. But bromide is a double-edged sword: not only has it replaced iodine, it may block the activity of iodine. That's also true for two more of iodine's chemical cousins — chlorine and fluoride, both of which are common in drinking water.

From 1971 to 2001 iodine intakes in the U.S. dropped by 50% (estimated by urine output)
Wheat, milk, less salt, floride

He estimates that 50-60% of the population is low, and 20-30% are very low

If you eat a lot of soy products, cut back — especially unfermented soy (e.g., soy milk, soy cheese, and soy protein added to food). Large amounts of soy can block thyroid function, though this is less of a problem with fermented soy products, like tempeh and tofu.
If your local water contains fluoride, consider a filter that eliminates it. Avoid bromide, too, when you can. (One unusual source: chemicals added to hot tubs to stop the growth of unwanted bacteria. There are other options available.)

Less Iodine, More Likely To Gain Weight

Researchers from Spain analyzed six years of health data from nearly 800 people. They found that those with the lowest levels of iodine also had the highest BMI (body mass index), and were more likely to become overweight during the six years of the study.
References

"Thyroid hormone levels predict the change in body weight: a prospective study." Soriguer F, Valdes S, Morcillo S, Esteva I, Almaraz MC, de Adana MS, Tapia MJ, Dominguez M, Gutierrez-Repiso C, Rubio-Martin E, Garrido-Sanchez L, Perez V, Garriga MJ, Rojo-Martinez G, Garcia-Fuentes E. Eur J Clin Invest. 2011 Apr 7. doi: 10.1111/j.1365-2362.2011.02526.x. [Epub ahead of print]
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Iodine: added to flour, water and milk in areas of deficiency
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Wikipedia http://en.wikipedia.org/wiki/Iodine_deficiency
The breast strongly and actively concentrates iodine into breast-milk for the benefit of the developing infant. Iodine helps prevent breast cancer by various pathways
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http://altmedangel.com/iodine.htm 
How to Self-Test for an Iodine Deficiency

1. Dip a cotton ball into USP Tincture of Iodine. 

2. Paint a 2 inch circle of iodine on your soft skin, like the inner part of your thigh or upper arm.

3. Wait. -- If the yellowish stain disappears in less than an hour; it means your body is lacking crucial iodine and has soaked it up. If the stain remains for more than four hours, you iodine levels are fine.
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http://www.womentowomen.com/hypothyroidism/iodinedeficiency-thyroidhealth.aspx 

But many people don’t know that flour isn’t iodized anymore, and iodization of salt is still voluntary in the US — only one-fifth of our salt is actually iodized. In reading further, I’ve found that we’re trending back toward iodine deficiency. Iodine intake has declined 50% in North America in the past 30–40 years, and this is consistent with what I’m seeing in my patients.

As recently as 2004, the New England Journal of Medicine defined our iodine status here in the US as “marginal,” based on data acquired from the International Council for the Control of Iodine Deficiency Disorder and the World Health Organization (WHO). More specifically, the WHO data suggest the greater risk in the US is not iodine deficiency per se but iodine-induced hyperthyroidism (overproduction of thyroid hormones) or iodine-induced hypothyroidism. Interestingly, both these problems can occur when people who are already iodine-deficient are given too much iodine, too quickly. I believe practitioners need to proceed more cautiously when prescribing iodine supplements, slowly bringing levels up rather than overloading right up front. (More on our treatment protocol for iodine deficiency below.) But the WHO perspective seems to confirm that iodine deficiency does exist here in the US.

Iodophobia. Iodine is one of the essential nutrients that you can get too much of. So both excess iodine and iodine deficiency can impair thyroid function and lead to elevated thyroid-stimulating hormone (TSH) levels. But it’s likely that if you are iodine-replete, you’re less sensitive to excess iodine than people with chronically depleted levels.

Individual sensitivity to iodine varies widely, but in the past 10–15 years, experts have found that overall, we are “remarkably tolerant to high intakes of iodine.” It appears that low or high iodine intake is something we get used to over long periods of time — though we’ll always need a certain amount. People living in some coastal regions of Japan regularly consume as much as 50,000–80,000 mcg of iodine daily!

The problem with other halogens. Iodine deficiency may also be related to other halogens — non-metals such as fluoride, chloride, and bromide, which are replacing iodine in the body. Most public water drinking supplies include the first two. Perchlorate (which may derive from rocket propellant, Chilean nitrate fertilizers, or other sources) is known to inhibit iodine transport in the body and thyroid function. Some scientists believe the omnipresence of perchlorate is “putting future generations in peril.”

Bromide is also widely present — in soil and crop fumigants as well many foods and drugs. In the 1960’s, iodine was added as an anticaking agent to bakery products, but because of misplaced fears of iodine toxicity (“iodophobia” ), it was replaced with bromine in the 1980’s. So we’re ingesting a lot of these halides, which research suggests compete with iodide for absorption and uptake in the body. This means they function as goitrogens (substances that suppress thyroid function by interfering with iodine uptake/accumulation).

Skidmore, B. 2007. Iodine deficient? A simple self-test can show you now. URL: http://www.content4reprint.com/health/nutrition/iodine-deficient-a-simple-self-test-can-show-you-now.htm (accessed 05.19.2009).

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http://hypothyroid.mivox.com/supplements/iodine_deficiency_testing_yourself__and_treatment 
So, you’ll need a bottle of tincture of iodine (2%), the standard orange antiseptic liquid from grandma’s medicine cabinet (You may need to ask at the pharmacy. My local store doesn’t stock it in the first aid/band-aid aisle). Swab a silver-dollar sized circle on the inside of your arm, and watch it for the next 24 hours. If you are not iodine deficient, the circle should keep a strong orange color for the whole 24 hours. If it fades before then, you could use iodine supplementation.
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http://www.celluliteinvestigation.com/2010/10/the-skin-patch-test-for-iodine-deficiency.html 
How fast does the iodine fade if I am iodine deficient?

As I researched this question, I started to notice the first cracks in the patch test theory. I could not find a standardized timeframe to help gauge the level of iodine deficiency. One source said that if the iodine absorbed within 4 hours, it was an indicator of normal iodine levels. Another source said 4 hours was a sign of extreme deficiency. Hmmm… that’s strange.

Most reputable sources seemed to have the same ballpark figures.  Anything under 4 hours indicates iodine deficiency (Dr Lynn August suggests 6 hours is more accurate).  And most sources agree that a patch lasting more than 24 hours is an indicator of iodine sufficiency.  But the discrepancies made me wonder how accurate this test can be.
Is the iodine patch test a reliable indicator of iodine deficiency?

I was fortunate to find an article by Dr. Guy Abraham addressing this very question. Dr. Abraham is the physician who introduced Dr. Brownstein to the ground-breaking research on iodine (Dr. Brownstein is the author of this month’s Cellulite BOTM, Iodine: Why You Need It, Why You Can’t Live Without It). The two docs have been coordinating their research on iodine for several years.

Dr. Abraham explains that iodine is absorbed through the skin, but the absorption of topical iodine is not an accurate indicator of iodine deficiency because of other factors that can affect the absorption rate.

    For example, if iodine is reduced to iodide by the skin, the yellow color of iodine will disappear because iodide is white… The evaporation of iodine from the skin increases with increased ambient temperatures and decreased atmospheric pressure due to weather conditions and altitudes.  For example, the yellow color of iodine will disappear much faster in Denver, Colorado at 5,000 feet above sea level then Los Angeles, California at sea level, irrespective of the amount of bioavailable iodine.1

Dr. Abraham recommends the iodine loading test, which I also mentioned in last week’s post (see, 3 Tests for Iodine Deficiency).

While the iodine loading test is undoubtedly more accurate, I believe there is still a place for the iodine patch test –as long as you understand its limitations.  The patch test should not be used to make a diagnosis, but I can see how it could be a helpful way to monitor the progress of an effort to restore iodine levels in the body (especially for us laymen).
The results of my iodine patch test

I attempted the iodine patch test twice this week, and both times the patch lasted over 12 hours. This seems right to me.  In addition to my efforts to eat a nutrient-dense diet, I’ve been supplementing with kelp (off and on) for over a year.  And as you know, I started taking an iodine supplement from Standard Process two months ago in addition to eating iodine-rich foods such as shrimp, mussels, and the infamous shrimp stock (I’m still holding out for my shrimp stock theory!).

For my situation, I am more curious to know how the added iodine is affecting the level of fluoride in my body. The patch test won’t help me there, but the iodine loading test might provide some answers. More on this next week…
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http://www.optimox.com/pics/Iodine/updates/UNIOD-02/UNIOD_02.htm   great science

To summarize the results of their experiments:

    Free iodine penetrates through the unbroken skin.
    Approximately 88 per cent of the iodine evaporate from the surface within three days.
    Colloidal iodine evaporates somewhat more quickly than tincture of iodine; Lugol’s solution is more stable than either of them.
    The influence of ambient temperature on the evaporation of iodine is significant: within the first minute, the losses of iodine by evaporation are: 10-15% at 9° c; 18-25% at 24° c; and 35% at 37° c.
    The remaining iodine on the skin following evaporation of 88% of the total iodine, approximately 12 per cent, is at the disposal of the body, and penetrates through the skin. The bioavailability of the remaining 12% of the skin iodine is very gradual.
    The fate of iodine in all above experiments is the same whether iodine is applied to the skin in the form of an alcoholic solution or in colloidal suspension. (For the reader’s information, the alcoholic solution is tincture of iodine and the colloidal suspension is a saturated aqueous solution of diatomic iodine, I2 ).
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Swiss fortification now at 20 mg/kg = 20 micrograms per gram of salt
So 2 grams of their salt now had 40 micrograms of Iodine, vs US has 70 micrograms/gram