Iodine public health nutrition (was: More Cities….)
Question:
– Hide quoted text — Show quoted text – True, iodine excess toxicity can happen, but at most to only 1-in-10 people (or much fewer) eating perhaps a 3 milligram (3000 microgram) daily seaweed/kelp diet. (I think RDA is 150 micrograms.) In short, this is Sean, You brought up some issues that I had never considered. For iron, the toxicity is only going to be seen in people with a specific genetic makeup, with the correct set of genes, excess iron is never going to be hepatotoxic, it will only be GI toxic. It’s quite possible that iodine is in a similar situation, the thyroid gland can protect itself from iodine toxicity unless a specific set of genes is present. This is the main reason why the U.S. stopped mandating that all salt sold had to have iodine in it. Do you know about what year this happened? I don’t know when the act mandating that iodine be added to all salt in the U.S. was repealed. Thyroid versus the several adrenals family being about equally important for protein metabolic enzyme replication from DNA, I’ve concluded that adrenal problems are far more difficult to deal with as a practical matter. I’ve never really covered the adrenals other than their very high levels of vitamin C. Dietary factors that affect adrenal function is an area that I have not gotten into. Just for the thyroid, it was really too much for me to handle. You think that glandular extracts help with both thyroid and adrenal problems. Both the thyroid and the adrenals would have been eaten in the past when an animal was killed. For carnivores today, there does not seem to be a sharing system, status in the pride determines who gets first shot at the kill. I’ve read that during the caveman period, evidence has been found that older people who could not hunt where kept alive. They obviously were feed by those that could hunt. Modern man has apparently lost his instinct for seeking out specific foods that are needed for human health. I wonder if the thyroids and adrenals were reserved for certain people in the clan whenever a kill came in?
I stopped buying iodized salt when I started eating fish. When we were kids, we learned in school that people who ate fish got enough iodine. Also, now days we eat food grown all over the place and do not have to rely on food grown locally which may be grown from iodine depleted soils. My concern was that I might be getting too much iodine. Dolores
Response:
– Hide quoted text — Show quoted text – As someone who had a goiter, I can’t believe what you just said. You mean that both the lack of iodine AND iodine toxicity are capable of causing a goiter? I never knew that and always assumed it was due to a lack of iodine. [...] Whitney [snip] With too much iodine stored in the thyroid gland, the gland is damaged and this damage causes gland enlargement. [...] Iodine deficiency and iodine toxicity can both knock out the thyroid gland. True, iodine excess toxicity can happen, but at most to only 1-in-10 people (or much fewer) eating perhaps a 3 milligram (3000 microgram) daily seaweed/kelp diet. (I think RDA is 150 micrograms.) In short, this is U.S./Europe unlikely unless one has taken radiographic contrast drugs, or taken more frequently, other synthetic drugs containing high iodine content (for one drug I think 9 mg iodine content per dose was mentioned). And even then, problems only if one’s genes complain, which is often no more than a few hours of probably harmless fever. Whether or not one gets a goiter or hypothyroidism from -excess- iodine is muchly dependent on one’s genes and personal history of iodine intake. (Search Pubmed for: iodine excess goiter) To quote Woeber KA, 1991, review: "An autoregulatory mechanism within the thyroid serves as the first line of defense against fluctuations in the supply of iodine… The pathologic consequences of iodine excess will ensue only when thyroid autoregulation is defective, in that escape from the Wolff-Chaikoff effect [very large quantity of iodine inhibits thyroid hormone synthesis] cannot occur, or when autoregulation is absent. Defective autoregulation characterizes the fetal and neonatal thyroid, Hashimoto’s thyroiditis, radioiodine or surgically treated Graves’ hyperthyroidism, the thyroid of patients with cystic fibrosis, and the thyroid that has been exposed to weak inhibitors of the organic binding of iodine. In these circumstances, the provision of excess iodine may lead to iodide goiter with or without hypothyroidism." In my previous post to this thread, I quoted Adelle Davis’ report of Saxena K M, et al, (Science 138, 430, 1962), suggesting that adults need 3 to 4 mg iodine daily, with Davis’ rationale that Japanese were doing thyroid-well on about 3 mg daily. More recently Konno N, et al, 1994, studied Japanese coastal seaweed-eating villages and concluded in part that "hypothyroidism is more prevalent and marked in subjects consuming further excessive amounts of iodine". However, in the abstract he reported on urine iodine levels, not diet, and the prevalence of hypothyroidism varied surprisingly from zero to a low 9.7%. Therefore Saxena, 1962, is not proved incorrect for 90%+ of population. Pennington JA, 1990, review stated: "It is concluded that some individuals can tolerate very high levels of iodine with no apparent side effects and that iodine intakes less than or equal to 1.000 mg/day are probably safe for the majority of the population, but may cause adverse effects in some individuals." Laurberg P, 2001, review said that elderly subjects had more frequent hypothyroidism from moderate and mild iodine excess (again this was a study of urine, not diet). This is the main reason why the U.S. stopped mandating that all salt sold had to have iodine in it. Do you know about what year this happened? Thyroid problems can be one of the most difficult areas of human metabolism to deal with. Thyroid versus the several adrenals family being about equally important for protein metabolic enzyme replication from DNA, I’ve concluded that adrenal problems are far more difficult to deal with as a practical matter. As for the incidence of adrenal trouble, consider that every disease which responds to steroid drugs may well have a low adrenal cause or contribution. This may include all of the autoimmune diseases. Because, of three major types of functional thyroid trouble –hypothyroidism, Hashimoto’s thyroiditis, and hyperthyroidism– IIRC, the first two respond well to natural thyroid extract, with no expectation of long term side effects. OTOH, the adrenal family is larger and more difficult to replace because of steroid side effects, as well as complicated interactions with other hormones and their pre-hormones. I have tried to better understand this particular problem area to help many who have come to sci.med.nutrition because of overactive or underactive thyroids. There may be some dietary, supplement and/or herbal approaches that might help but I have never felt that I knew enough to really comment on this area. Marty B. After a fair amount of non-pro study, I too am frustrated by the available supplement and/or herbal approaches to hypothyroidism as a specific reductionist symptom (there are holistic tonics like ginseng to try). Reductionist herbal hypothyroidism treatments exist, but seem either iffy (supplements) or use rare and potent herbs which require dosing more like drugs. If however, one views thyroid extract as a glandular food, rather than its legal status as pharma, then it is a natural medicine with exceptional efficacy and nearly zero side effects. Old docs are more likely to know this, but new docs probably don’t. Thyroid hormones can be and have been overused by some of those docs and patients involved in weight control issues. Don’t do that, it causes prescribing trouble for those of us who do well on thyroid extract clinical trials, but can’t pass the official thyroid serum tests. Sean
It’s not a matter of "passing" the TSH test. The interplay between pituitary/hypothalamic release of pulsatile TRH and TSH, thyroid release of triiodothyronine (T3) and thyroxine (T4), feedback suppression of TRH and TSH, and peripheral conversion from T3 to T4 is quite complex. By giving you only the lower potency T4 in the synthetic product, your body can regulate conversion to the higher potency T3 as needed. That way you get a much more (I hate to use this word) natural balance of thyroid hormone since the body has at least partial control. Additionally, the half life of the lower potency hormone is measured in days while the half life of the high potency hormone is measured in hours. People taking dried thyroid extracts frequently have transient hyperthyroid symptoms. On the other hand, it is usually fairly simple to regulate the dose of synthetic T4 so that TSH, free T4, and free T3 are all within the range normally maintained by people without thyroid disease. The excessive suppression of TSH due to the higher level of T3 with the use of dried extracts may be a significant risk factor for osteoporosis.
Response:
True, iodine excess toxicity can happen, but at most to only 1-in-10 people (or much fewer) eating perhaps a 3 milligram (3000 microgram) daily seaweed/kelp diet. (I think RDA is 150 micrograms.) In short, this is
Sean, You brought up some issues that I had never considered. For iron, the toxicity is only going to be seen in people with a specific genetic makeup, with the correct set of genes, excess iron is never going to be hepatotoxic, it will only be GI toxic. It’s quite possible that iodine is in a similar situation, the thyroid gland can protect itself from iodine toxicity unless a specific set of genes is present. This is the main reason why the U.S. stopped mandating that all salt sold had to have iodine in it. Do you know about what year this happened?
I don’t know when the act mandating that iodine be added to all salt in the U.S. was repealed. Thyroid versus the several adrenals family being about equally important for protein metabolic enzyme replication from DNA, I’ve concluded that adrenal problems are far more difficult to deal with as a practical matter.
I’ve never really covered the adrenals other than their very high levels of vitamin C. Dietary factors that affect adrenal function is an area that I have not gotten into. Just for the thyroid, it was really too much for me to handle. You think that glandular extracts help with both thyroid and adrenal problems. Both the thyroid and the adrenals would have been eaten in the past when an animal was killed. For carnivores today, there does not seem to be a sharing system, status in the pride determines who gets first shot at the kill. I’ve read that during the caveman period, evidence has been found that older people who could not hunt where kept alive. They obviously were feed by those that could hunt. Modern man has apparently lost his instinct for seeking out specific foods that are needed for human health. I wonder if the thyroids and adrenals were reserved for certain people in the clan whenever a kill came in? — Marty B. "You are what you eat." http://centernet.okstate.edu/nutrition/index.html
Response:
– Hide quoted text — Show quoted text – [snip] Reductionist herbal hypothyroidism treatments exist, but seem either iffy (supplements) or use rare and potent herbs which require dosing more like drugs. If however, one views thyroid extract as a glandular food, rather than its legal status as pharma, then it is a natural medicine with exceptional efficacy and nearly zero side effects. Old docs are more likely to know this, but new docs probably don’t. Thyroid hormones can be and have been overused by some of those docs and patients involved in weight control issues. Don’t do that, it causes prescribing trouble for those of us who do well on thyroid extract clinical trials, but can’t pass the official thyroid serum tests. Sean It’s not a matter of "passing" the TSH test. I was using double entendre to describe docs’ resistance to prescribing thyroid extract as an empirical treatment, when it can’t be AMA-justified with thyroid hormones blood tests. The interplay between pituitary/hypothalamic release of pulsatile TRH and TSH, thyroid release of triiodothyronine (T3) and thyroxine (T4), feedback suppression of TRH and TSH, and peripheral conversion from T3 to T4 is quite complex. (I assume that’s a typo, and you meant ‘conversion from T4 to T3′.)
Yep, sorry. T4 is deiodinated to T3. By giving you only the lower potency T4 in the synthetic product, your body can regulate conversion to the higher potency T3 as needed. That way you get a much more (I hate to use this word) natural balance of thyroid hormone since the body has at least partial control. This theory only works for low thyroid supply, not thyroid uptake disorders which are a suspect factor in non-blood-testable hypothyroidism with Low Body Temperature. This theory also does not work for Wilson’s Syndrome, described as a significant reduction of T4 to T3 conversion.
While there are people who do not perform peripheral conversion well, they probably aren’t that common. Wilson’s syndrome is the creation of Dr. Wilson and it is not supported by any scientific data. The symptoms could just as easily be labeled "candidiasis". There is a lot of variation in normal body temperature. To label everybody who runs on the cool end of the spectrum as having a "syndrome" creates an awful lot of sick people. Particularly since most people with "low" body temperature are young and healthy. There is a natural circadian rhythym to body temperature which is completely normal and very very common. If you measured a.m. body temperature in most healthy people, they would be diagnosed with "Wilson’s syndrome". [...] On the other hand, it is usually fairly simple to regulate the dose of synthetic T4 so that TSH, free T4, and free T3 are all within the range normally maintained by people without thyroid disease. But it turned out, not so simple as hoped. The practical problem as I understand it, is that exactly TSH suppressive doses of T4 are hard to maintain with temperature, activity, and diet changes by the patient. This has historically led to somewhat over-suppressive doses which then led to osteoporosis from sub-clinical -hyper-thyroidism. (And as I mentioned, it does not work for thyroid uptake disorders.)
Of course, you don’t get as good results from medication as you do from a healthy thyroid, but maintaining T4, T3, and TSH within normal limits isn’t that tough. It is certainly easier to do it with synthetic T4 than with thyroid extracts. There is no reason to assume that sub-clinical hyperthyroidism (iatrogenic would be a better description) from thyroid extracts is somehow better than closer control with synthetic T4. Additionally, the half life of the lower potency hormone is measured in days while the half life of the high potency hormone is measured in hours. People taking dried thyroid extracts frequently have transient hyperthyroid symptoms. How frequently? I’ll want to review any studies you wish to cite, but I expect that the transient symptoms are signs of changes in dose requirements. Due to the recent decades of desperation and litigation by weight control patients, docs and their group practice lawyers resist allowing patients to set their own thyroid extract dose. But I suggest that is an option which should be considered first, with occasional medical observation, to prevent long term osteoporosis especially in older women. If that doesn’t work well, thyroxine therapy is always a fallback treatment.
Switching to thyroxine after a woman (or for that matter a man) develops osteoporosis as a consequence of iatrogenic hyperthyroidism is too late. Yearly observation to maintain thyroid hormones within the normal range to _prevent_ osteoporosis is a much better strategy. Unfortunately, allowing people free access to abusable drugs, does not always mean that they will make the best long term choices. Many young women will smoke or stop using insulin for weight control. It is unlikely that they would carefully regulate thyroid hormone use to prevent osteoporosis. A young endocrinologist I saw in a large city had this notion that thyroid requirements aren’t at all seasonal. I can understand an GP/FP not knowing this, but how was that omitted from his med school endocrinology specialty? The endocrinologist stated that his evidence was his experience with his patient group. I suggested that his very comfortable upper middle class patients were rarely exposed to more than brief changes in temperature, summer or winter. And, of course, he was probably treating them with overly TSH-suppressive doses of thyroxine.
Thyroxine is no more suppressive than dried animal thyroid extracts. At least some autoregulation is possible with synthetic thyroxine. I don’t know that there are very many Americans of whatever income class who don’t have central heating, adequate (usually overadequate) caloric intake, and protective clothing so that they too are protected from more than brief changes in temperature. The endocrinologist that you mention is probably striving to maintain his patients so that they are not overly suppressed. Aggressive TSH suppression seems to be the goal of alternative practitioners and seems to be what you are advocating. The excessive suppression of TSH due to the higher level of T3 with the use of dried extracts may be a significant risk factor for osteoporosis. It also may not be a significant risk for the exact reason that you previously mentioned. Thyroid extract T3 content tends to warn the patient when taking too much.
Some people are more sensitive to excessive thyroid medication that others. There is no evidence that excessive dessicated thyroid extract is any better or any worse than excessive synthetic thyroid. However, it is easier for the clinician to avoid excessive thyroid dosing with the synthetic forms by taking advantage of the body’s autoregulation of peripheral thyroid conversion.
Response:
It’s not a matter of "passing" the TSH test. The interplay between pituitary/hypothalamic release of pulsatile TRH and TSH, thyroid release of triiodothyronine (T3) and thyroxine (T4), feedback suppression of TRH and TSH, and peripheral conversion from T3 to T4 is quite complex. By giving you only the lower potency T4 in the synthetic product, your body can
Please also remember that the interconversion of T3/T4 is selenium dependent.
Response:
As someone who had a goiter, I can’t believe what you just said. You mean that both the lack of iodine AND iodine toxicity are capable of causing a goiter? I never knew that and always assumed it was due to a lack of iodine. Also, what is "goitrogen"? I feel so lost! Thanks, Whitney Whitney, A lack of iodine will make the thyroid gland enlarge to try to improve the uptake of iodine. With too much iodine stored in the thyroid gland, the gland is damaged and this damage causes gland enlargement.
Which leads to the next question – what is the therapeutic range (index)? Is it easier to have too little or too much iodine? Considering the RDA is 150 mcg and the therapeutic dose is 6 mg, I’m thinking it’s a bit easier to come up short. But maybe a bit of math is in order. http://www.nutritionnewsfocus.com/archive/a2/NewIodRec.html So, how many mcg of iodine is ther in a teaspoon of salt? Well, at .006 to 0.01% KI and the molecular weight of KI, and assuming a teaspoon is 5 gm, about 37.5 mcg. With the RDA at 150 and the recommended maximum dose of 1100 and the toxic dose at 6 times that, one would have to eat less than an ounce to meat the RDA, about 5 ounces to get to the upper limit of safe and almost two pounds to get to a point where it has been shown to have a therapeutic affect on the thyroid. http://www.nutritionnewsfocus.com/archive/a2/NewIodRec.html However, on the other side, in normo-iodic children, median urinary clearance is about 100 mcg/l – so one would assume a replacement need of about that daily. This is consistent with the RDA. Under this set of parameters, it appears that the risk of iodine deficiency without supplementation exceeds the risk of iodine related hyperthyroidism associated with over dosing. Just math, Roger, just math. amp – Hide quoted text — Show quoted text – Goitrogens are a class of plant chemicals called glucosinolates that are probably produced to prevent fungal disease. Plant enzymes are needed to generate large amounts of the glucosinolates and cooking the food destroys these enzymes. Even in areas where human intake of these goitrogens is high, poor iodine intake is probably also needed to produce goiter. http://ace.orst.edu/info/extoxnet/faqs/natural/goi.htm With a good intake of iodine, goitrogens are not thought to pose much of a problem to human health. Iodine deficiency and iodine toxicity can both knock out the thyroid gland. This is the main reason why the U.S. stopped mandating that all salt sold had to have iodine in it. Thyroid problems can be one of the most difficult areas of human metabolism to deal with. I have tried to better understand this particular problem area to help many who have come to sci.med.nutrition because of overactive or underactive thyroids. There may be some dietary, supplement and/or herbal approaches that might help but I have never felt that I knew enough to really comment on this area.
Response:
As someone who had a goiter, I can’t believe what you just said. You mean that both the lack of iodine AND iodine toxicity are capable of causing a goiter? I never knew that and always assumed it was due to a lack of iodine. Also, what is "goitrogen"? I feel so lost! Thanks, Whitney
Whitney, A lack of iodine will make the thyroid gland enlarge to try to improve the uptake of iodine. With too much iodine stored in the thyroid gland, the gland is damaged and this damage causes gland enlargement. Goitrogens are a class of plant chemicals called glucosinolates that are probably produced to prevent fungal disease. Plant enzymes are needed to generate large amounts of the glucosinolates and cooking the food destroys these enzymes. Even in areas where human intake of these goitrogens is high, poor iodine intake is probably also needed to produce goiter. http://ace.orst.edu/info/extoxnet/faqs/natural/goi.htm With a good intake of iodine, goitrogens are not thought to pose much of a problem to human health. Iodine deficiency and iodine toxicity can both knock out the thyroid gland. This is the main reason why the U.S. stopped mandating that all salt sold had to have iodine in it. Thyroid problems can be one of the most difficult areas of human metabolism to deal with. I have tried to better understand this particular problem area to help many who have come to sci.med.nutrition because of overactive or underactive thyroids. There may be some dietary, supplement and/or herbal approaches that might help but I have never felt that I knew enough to really comment on this area. — Marty B. "You are what you eat." http://centernet.okstate.edu/nutrition/index.html
Response:
– Hide quoted text — Show quoted text – What has iodide in salt got to do with fluoride in water supplies? They are both government regulated public health plans to control disease, but iodine nutrition is market implemented. Both are government mandates. Fluoride has been left to the individual states to mandate. Iodine was a Federal Government mandate first written into Federal Law in 1924. With this Federal Law, no salt sold in the U.S. could be sold without iodine added to it. That law has since been repealed. Why? Iodine toxicity. Sweden has now banned the addition of iron to flour. Why? Iron toxicity. In today’s U.S. market, selling salt with iodine is primarily market driven (some people will not buy the salt that does not have iodine added to it). Thyroid enlargement in the U.S., which was at one time primarily driven by iodine deficiency, is now primarily driven by iodine toxicity and/or goitrogen intake. Giving everybody in a country iodine or iron if they really do not need these minerals can end up causing more disease than what the Government mandate foresaw. I guess you could say that Big Brother does not always know what is best for us but if you try to tell Big Brother this, you are in for the fight of your life.
As someone who had a goiter, I can’t believe what you just said. You mean that both the lack of iodine AND iodine toxicity are capable of causing a goiter? I never knew that and always assumed it was due to a lack of iodine. Also, what is "goitrogen"? I feel so lost! Thanks, Whitney
Response:
Iodine was a Federal Government mandate first written into Federal Law in 1924. With this Federal Law, no salt sold in the U.S. could be sold without iodine added to it. That law has since been repealed. Why? Iodine toxicity. Sweden has now banned the addition of iron to flour. Why? Iron toxicity.
Thanks for that info. I didn’t know that. Giving everybody in a country iodine or iron if they really do not need these minerals can end up causing more disease than what the Government mandate foresaw. I guess you could say that Big Brother does not always know what is best for us but if you try to tell Big Brother this, you are in for the fight of your life.
Yes. Some people describe this by saying that do-gooder actions often have unforeseen consequences. But in your examples, the adverse effects are quite foreseeable.
Response:
What has iodide in salt got to do with fluoride in water supplies? They are both government regulated public health plans to control disease, but iodine nutrition is market implemented.
Both are government mandates. Fluoride has been left to the individual states to mandate. Iodine was a Federal Government mandate first written into Federal Law in 1924. With this Federal Law, no salt sold in the U.S. could be sold without iodine added to it. That law has since been repealed. Why? Iodine toxicity. Sweden has now banned the addition of iron to flour. Why? Iron toxicity. In today’s U.S. market, selling salt with iodine is primarily market driven (some people will not buy the salt that does not have iodine added to it). Thyroid enlargement in the U.S., which was at one time primarily driven by iodine deficiency, is now primarily driven by iodine toxicity and/or goitrogen intake. Giving everybody in a country iodine or iron if they really do not need these minerals can end up causing more disease than what the Government mandate foresaw. I guess you could say that Big Brother does not always know what is best for us but if you try to tell Big Brother this, you are in for the fight of your life. — Marty B. "You are what you eat." http://centernet.okstate.edu/nutrition/index.html
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