HER2 Support Group Forums - View Single Post - Iodine deficiency ! - falling intakes - goitregens

R.B. · 09-15-2018, 05:00 AM

I was recently in Valais, a very beautiful alpine area of Switzerland, (sadly just for a couple of days), and in a random conversation it was suggested that women in the area were worried by what appeared to them to be a greater number of breast cancer cases in the area than might be expected. They were puzzling as to possible factors that impacted them that could potentially be implicated including localized water supplies. I recalled from general reading the Alpine Switzerland was an area at risk of low iodine intake and goiter. Historically Valais was a region known for being at high risk of goiter, and so like other iodine deficiency risk areas historically exhibited the impacts of severe iodine deficiency including cretinism. Supplementation of salt and wider food intake and distribution has alleviated the risk of severe iodine insufficiency, but arguably the risks of mild insufficiency remain relevant.

Iodine insufficiency, as identified in this thread, is arguably a risk factor for occurrence and progression of breast cancer.

“The regular monitoring of urinary iodine excretion of Swiss population groups revealed a decrease in the iodine supply in children and pregnant women between 2004 and 2009 [9].” (See below for reference *)

Iodine intake has been a long-term concern in some European countries including Switzerland, and steps have been taken by Governments to reduce iodine insufficiency, but despite this there are indications (e.g. above) that levels in children and women are again falling in recent years. Large numbers of people are insufficient in many other countries as well, including the UK where there is no national iodisation program.

A report Iodine supply in Switzerland: Current Status and Recommendations, was prepared in 2012 for the Federal Commission for Nutrition https://www.google.com/url?sa=t&rct=...5flcQ0Sxir53sk

Those who eat no dairy, marine fish, or bread (where made with iodised salt), and avoid salt (so reduce iodised salt intake) and or use other salts e.g. sea salt, are at particular risk of insufficiency. Those who use organic dairy products (as against non-organic) are at greater risk or low iodine/iodide.

To add to the complications it appears iodine and iodide are not metabolized in exactly the same way. As discussed previously, only iodine was shown to potentially ameliorate mastagla, and interestingly the breast has specific iodine import mechanisms. I do not think it is known exactly in what forms and proportions iodide/iodine is found in dairy products. Clearly iodised salt and products made with iodised salt, only contains iodide. Clearly much research is still needed so these issues and their implications, including for national supplementation strategies, are better understood.

Reasons for falling intakes:

• The main dietary sources of iodine are

Dairy (organic milk has lower amounts)
Fish (marine - fresh water fish contain little iodine)
Iodised salt
Flour if fortified or iodised salt added
Eggs (depending on diet of hens)

• Areas of Switzerland are know to be at higher risk of goitre due to lower soil so food levels due to greater water flows through soils. Risks are likely higher in mountain areas.
• Local dairies are still common, and iodine status in the cattle will depend pasture content, on feed used, and if the milk is organic (so different feed type).
• Alpine pastures / soils are logically at greater risk of containing low iodine.
• Globally greater numbers avoid dairy foods
• Fish intake is likely lower in inland areas.
• Salt intake is falling due to health concerns
• Specialty salts such sea salt are generally not iodised
• Iodine can sublime out of iodised salt in storage
• It is not clear if flour is fortified and if so how widespread the usage of it is, and or to what extent iodized salt is always used in the small local bakeries which still exist and are widely supported.

In addition effects of insufficiency would be compounded where milk was included in the diet but itself contained goitrogenic products derived form plants in feeds or pastures (see below in upcoming following post)

Relevance of dairy products inducing the difference in iodine content between organic and non-organic milk

Dairy products as essential sources of iodine in the Swiss population
https://www.ethz.ch/content/dam/ethz...eet%20MIOD.pdf

"Iodine deficiency is estimated by the WHO to be the leading cause of preventable mental retardation worldwide. National surveys have shown sufficient iodine intake in school aged children and pregnant women in Switzerland but other groups, such as weaning infants and women of reproductive age, have low intakes. Along with iodized salt, milk and dairy products are supplying more than half of the iodine intakes in Switzerland."

Iodine in Swiss milk depending on production (conventional versus organic) and on processing (raw versus UHT) and the contribution of milk to the human iodine supply*

Journal of Trace Elements in Medicine and Biology Volume 46, March 2018, Pages 138-143
https://www.sciencedirect.com/scienc...46672X17305308

“A total of 110 samples of conventional and organic ultra-heat treated (UHT) whole milk were collected in the period between 1 May 2013 and 30 April 2014 from two large-scale companies, processing milk from two regions in Switzerland. The iodine concentration in organic milk (average 71 ± 25 μg/l) was significantly lower than in conventional milk (average 111 ± 26 μg/l) and varied between suppliers. Milk iodine concentration varied according to the month of collection in organic and conventionally produced milk, with lowest values between August and October (organic milk 42 μg/l; conventional milk 75 μg/l) and highest values in January (organic milk 99 μg/l; conventional milk 145 μg/l). Heat treatment did not influence iodine concentration. Since milk and dairy products are significant source of food-related iodine intake in Switzerland, consumers who prefer organic milk and dairy products are likely to have an inferior iodine status.”

“Iodine is an essential element for thyroid hormone production. A too low dietary iodine offer may create a thyroid hormone deficit with deficiency symptoms including cretinism, brain damage, irreversible mental retardation, deaf-mutism, and goitre. Iodine deficiency, with its various mental and physical consequences is part of the history of most European countries, especially in alpine regions of Austria, France, Italy, and Switzerland [1]. These regions are characterized by iodine deficient soils, where iodine has been washed away by glaciation [2].”

“The regular monitoring of urinary iodine excretion of Swiss population groups revealed a decrease in the iodine supply in children and pregnant women between 2004 and 2009 [9].”

https://www.ncbi.nlm.nih.gov/pubmed/29508687
The main determinants of iodine in cows' milk in Switzerland are farm type, season and teat dipping.
Br J Nutr. 2018 Mar;119(5):559-569. doi: 10.1017/S0007114517003798.

Levels of iodine in dairy products are as a generality higher in the UK than Switzerland and other European countries but the issues are the same. (despite this iodine insufficiency in the UK is widespread)(The UK has no national salt fortification strategy - see earlier posts)

Iodine concentration of organic and conventional milk: Implications for iodine intake.
July 2011The British journal of nutrition 107(7):935-40 https://www.researchgate.net/publica..._iodine_intake

“Organic milk was 42·1 % lower in iodine content than conventional milk (median iodine concentration 144·5 v. 249·5 ng/g; P < 0·001). There was no difference in the iodine concentration of either conventional or organic milk by area of purchase. However, a difference was seen in iodine concentration of organic milk by region of origin (P < 0·001). The lower iodine concentration of organic milk has public-health implications, particularly in view of emerging evidence of iodine deficiency in UK population sub-groups, including pregnant women. Individuals who choose organic milk should be aware that their iodine intake may be compromised and should ensure adequate iodine intake from alternative sources.”

(For 'nerds' - interesting data from the 1920s on cancer and goiter rates with a focus on Switzerland in a paper called Cancer and Goiter possibly suggesting some associations - cancer prevalence trends have clearly changed - https://www.jstor.org/stable/2331713...o_tab_contents - just posted as of general interest and old data can be hard to find)

09-15-2018, 05:00 AM	#121
R.B. Senior Member Join Date: Mar 2006 Posts: 1,843	Re: Iodine deficiency ! - falling intakes - goitregens - competition bromine and fluo I was recently in Valais, a very beautiful alpine area of Switzerland, (sadly just for a couple of days), and in a random conversation it was suggested that women in the area were worried by what appeared to them to be a greater number of breast cancer cases in the area than might be expected. They were puzzling as to possible factors that impacted them that could potentially be implicated including localized water supplies. I recalled from general reading the Alpine Switzerland was an area at risk of low iodine intake and goiter. Historically Valais was a region known for being at high risk of goiter, and so like other iodine deficiency risk areas historically exhibited the impacts of severe iodine deficiency including cretinism. Supplementation of salt and wider food intake and distribution has alleviated the risk of severe iodine insufficiency, but arguably the risks of mild insufficiency remain relevant. Iodine insufficiency, as identified in this thread, is arguably a risk factor for occurrence and progression of breast cancer. “The regular monitoring of urinary iodine excretion of Swiss population groups revealed a decrease in the iodine supply in children and pregnant women between 2004 and 2009 [9].” (See below for reference ) Iodine intake has been a long-term concern in some European countries including Switzerland, and steps have been taken by Governments to reduce iodine insufficiency, but despite this there are indications (e.g. above) that levels in children and women are again falling in recent years. Large numbers of people are insufficient in many other countries as well, including the UK where there is no national iodisation program. A report Iodine supply in Switzerland: Current Status and Recommendations, was prepared in 2012 for the Federal Commission for Nutrition https://www.google.com/url?sa=t&rct=...5flcQ0Sxir53sk Those who eat no dairy, marine fish, or bread (where made with iodised salt), and avoid salt (so reduce iodised salt intake) and or use other salts e.g. sea salt, are at particular risk of insufficiency. Those who use organic dairy products (as against non-organic) are at greater risk or low iodine/iodide. To add to the complications it appears iodine and iodide are not metabolized in exactly the same way. As discussed previously, only iodine was shown to potentially ameliorate mastagla, and interestingly the breast has specific iodine import mechanisms. I do not think it is known exactly in what forms and proportions iodide/iodine is found in dairy products. Clearly iodised salt and products made with iodised salt, only contains iodide. Clearly much research is still needed so these issues and their implications, including for national supplementation strategies, are better understood. Reasons for falling intakes: • The main dietary sources of iodine are Dairy (organic milk has lower amounts) Fish (marine - fresh water fish contain little iodine) Iodised salt Flour if fortified or iodised salt added Eggs (depending on diet of hens) • Areas of Switzerland are know to be at higher risk of goitre due to lower soil so food levels due to greater water flows through soils. Risks are likely higher in mountain areas. • Local dairies are still common, and iodine status in the cattle will depend pasture content, on feed used, and if the milk is organic (so different feed type). • Alpine pastures / soils are logically at greater risk of containing low iodine. • Globally greater numbers avoid dairy foods • Fish intake is likely lower in inland areas. • Salt intake is falling due to health concerns • Specialty salts such sea salt are generally not iodised • Iodine can sublime out of iodised salt in storage • It is not clear if flour is fortified and if so how widespread the usage of it is, and or to what extent iodized salt is always used in the small local bakeries which still exist and are widely supported. In addition effects of insufficiency would be compounded where milk was included in the diet but itself contained goitrogenic products derived form plants in feeds or pastures (see below in upcoming following post) Relevance of dairy products inducing the difference in iodine content between organic and non-organic milk* Dairy products as essential sources of iodine in the Swiss population https://www.ethz.ch/content/dam/ethz...eet%20MIOD.pdf "Iodine deficiency is estimated by the WHO to be the leading cause of preventable mental retardation worldwide. National surveys have shown sufficient iodine intake in school aged children and pregnant women in Switzerland but other groups, such as weaning infants and women of reproductive age, have low intakes. Along with iodized salt, milk and dairy products are supplying more than half of the iodine intakes in Switzerland." Iodine in Swiss milk depending on production (conventional versus organic) and on processing (raw versus UHT) and the contribution of milk to the human iodine supply* Journal of Trace Elements in Medicine and Biology Volume 46, March 2018, Pages 138-143 https://www.sciencedirect.com/scienc...46672X17305308 “A total of 110 samples of conventional and organic ultra-heat treated (UHT) whole milk were collected in the period between 1 May 2013 and 30 April 2014 from two large-scale companies, processing milk from two regions in Switzerland. The iodine concentration in organic milk (average 71 ± 25 μg/l) was significantly lower than in conventional milk (average 111 ± 26 μg/l) and varied between suppliers. Milk iodine concentration varied according to the month of collection in organic and conventionally produced milk, with lowest values between August and October (organic milk 42 μg/l; conventional milk 75 μg/l) and highest values in January (organic milk 99 μg/l; conventional milk 145 μg/l). Heat treatment did not influence iodine concentration. Since milk and dairy products are significant source of food-related iodine intake in Switzerland, consumers who prefer organic milk and dairy products are likely to have an inferior iodine status.” “Iodine is an essential element for thyroid hormone production. A too low dietary iodine offer may create a thyroid hormone deficit with deficiency symptoms including cretinism, brain damage, irreversible mental retardation, deaf-mutism, and goitre. Iodine deficiency, with its various mental and physical consequences is part of the history of most European countries, especially in alpine regions of Austria, France, Italy, and Switzerland [1]. These regions are characterized by iodine deficient soils, where iodine has been washed away by glaciation [2].” “The regular monitoring of urinary iodine excretion of Swiss population groups revealed a decrease in the iodine supply in children and pregnant women between 2004 and 2009 [9].” https://www.ncbi.nlm.nih.gov/pubmed/29508687 The main determinants of iodine in cows' milk in Switzerland are farm type, season and teat dipping. Br J Nutr. 2018 Mar;119(5):559-569. doi: 10.1017/S0007114517003798. Levels of iodine in dairy products are as a generality higher in the UK than Switzerland and other European countries but the issues are the same. (despite this iodine insufficiency in the UK is widespread)(The UK has no national salt fortification strategy - see earlier posts) Iodine concentration of organic and conventional milk: Implications for iodine intake. July 2011The British journal of nutrition 107(7):935-40 https://www.researchgate.net/publica..._iodine_intake “Organic milk was 42·1 % lower in iodine content than conventional milk (median iodine concentration 144·5 v. 249·5 ng/g; P < 0·001). There was no difference in the iodine concentration of either conventional or organic milk by area of purchase. However, a difference was seen in iodine concentration of organic milk by region of origin (P < 0·001). The lower iodine concentration of organic milk has public-health implications, particularly in view of emerging evidence of iodine deficiency in UK population sub-groups, including pregnant women. Individuals who choose organic milk should be aware that their iodine intake may be compromised and should ensure adequate iodine intake from alternative sources.” (For 'nerds' - interesting data from the 1920s on cancer and goiter rates with a focus on Switzerland in a paper called Cancer and Goiter possibly suggesting some associations - cancer prevalence trends have clearly changed - https://www.jstor.org/stable/2331713...o_tab_contents - just posted as of general interest and old data can be hard to find) Last edited by R.B.; 10-04-2018 at 04:28 PM..