While searching through steem for some good reads I stumbled upon a post written by 
First claim:
Iodine is an essential nutrient. The body does not make iodine, so you have to consume it.
Well, yes, iodine cannot be made by the body. If you take a look at a periodic table of elements – like this one – you will find an “I” in row 5, of the second column from the right. This means that iodine is one of the elements and if our body could make them, well, that would be a scientific wonder.
The modern food supply is no longer a reliable source of iodine, and 95% of Americans are deficient in it.
I was trying really hard to find information suggesting such a high level of iodine deficiency in Americans today. However, the only information I could find stated that there is no iodine deficiency in America (1). However, the same source states that roughly 40% of the world´s population is at risk for iodine deficiency. Another source states that due to salt iodization, deficiency in America and the developed world is rare (2). Yet another source states that Americans generally get enough iodine through iodized salt (3). I did find some scientific reviews that stated iodine deficiencies is still a concern in developed, European countries (4). In conclusion, yes, our body cannot make iodine. However, Americans get enough iodine through iodized salt and other nutritional sources. Iodine deficiency is still a concern in certain regions of the world.
There are iodine receptors in every cell of the body. Iodine stimulates the production of hormones, the body’s chemical messengers.
The first part is wrong. Not every cell in the body has iodine receptors. The receptors in the cell are for thyroid hormones (more specifically T3), which behave like steroid hormones and are nuclear transcription factors (5). The second part is a little bit more tricky to judge.
Word for word, this is probably more wrong than right. Iodine is needed to produce certain steroid hormones, the thyroid hormones T3 and T4, whose function I already mentioned (6). It is more an ingredient than stimulus. Yes, hormones are chemical messengers in our body. However, not the only ones. As a matter of fact, the all so demonized radicals are also chemical messengers (for example NO) (7). So that statement is somewhat misleading.
Because we live in an increasingly toxic world, iodine supplementation is crucial. Pharmaceuticals, food, water, and air contain high levels of heavy metals like mercury, lead, cadmium, and arsenic, and the halogens chlorine, fluorine, and bromine.
A scientific review confirms that concentration of endocrine disrupters and heavy metals increase in the developed world (8). I would also add soil to the list of things that contain heavy metals, as well as ourselves. Some metals are actually very important for us (like you would not be able to live without iron or calcium) (8). Well, if you are worried about halogens, you really should worry about iodine also, since it is a halogen, too! A definition of "high levels of heavy metals" would be nice.
All of these elements compete for the iodine receptor sites in the body.
As I already said, there are no iodine receptors. It is more accurate to say that heavy metals are interfering with the synthesis of thyroid hormone, which can cause disruptions in hormone homeostasis (9). Bromine and chlorine can actually compete with iodine for uptake into the thyroid (by competing to be taken up by a transporter) (10). A scientific article states that enocrine disrupters like bisphenol A (chemically similar to estrogen and steroid hormones in general) can bind the thyroid hormone receptors (11). The same article suggests that halogenated derivatives of bisphenol A have even higher binding affinities for thyroid receptors. Why are people taking iodine pills when exposed to radiation? Is that to prevent heavy metals to compete for iodine receptors? No. Taking potassium iodide pills as a prevention against radioactivity aims to saturate the thyroid gland with non-radioactive iodine, so that it does not absorb radioactive iodine when exposed to it (12)
Hormonal dysfunctions manifest as metabolic disorders and diseases such as:
- Diabetes
- Cancer
- Hyper- and hypothyroidism
- Goiter
- Cystic conditions
Yes, hormonal dysfunctions CAN manifest as these disorders. That is common knowledge I would say. However, this list is very vague and repetitive. For example, goiter is a symptom of hypothyroidism (3).
With enough iodine in the system, hormone production and enzyme activity runs more efficiently and metabolism is optimized.
Apart from very vague language this is mostly correct. The key here is enough iodine, not too little, but also not too much. The vague language actually implies some dangerous conclusions: iodine is responsible for all enzymes and the more iodine the better. First of all, iodine is not the main regulator for all enzymes. Second of all, iodine can be harmful. Too much iodine can actually cause hypothyroidism, as well as hyperthyroidism and other diseases among which are Hashimoto disease, Graves disease, certain thyroid cancers and thyrotoxicosis (2).
iodine supplementation immediately begins the excretion of halogens and heavy metals.
I could not find any scientific source dealing with iodine and its role on heavy metal excretion. In such a case it is better to not make any statements because it is probably more fiction than fact.
Conclusion
Iodine: An Essential Nutrient and Holistic Option for Detoxing Heavy Metals and Halogens is not scientific at all - luckily they do not claim to be. However, almost every statement made in this post seems to be half-truisms or just false information.I have to say that I like the fact that this group is trying to help people. However, this article is not valuable information. Additionally, they have re-posted this post from another account.
As always,
Cheers 