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Iodine And Hashimoto’s Disease

Iodine and Hashimoto's Disease

What You Need To Know About Hashimoto’s Disease And Iodine

Thyroid disorders have become quite a popular topic in the healthcare industry over the last few years.

As more awareness is being placed on this topic, scientists are also taking an interest to the topic and conducting clinical studies to assist the healthcare industry with providing better treatment options for patients suffering from these conditions.

Hashimoto’s disease is one of the most common disorders that are associated with Thyroid function.

This autoimmune disease is known to cause damage to Thyroid gland tissue, and leads to an underactive Thyroid gland. Iodine is a nutrient that shares quite a complex relationship with Thyroid function, Thyroid disorders and Hashimoto’s disease.

While iodine intake is needed for optimal Thyroid function, it does seem like excessive intake of this nutrient can be detrimental to a patient suffering from Hashimoto’s disease and an underactive Thyroid.

In this post, we’ll dig deeper into the complex relationship that exists between iodine intake, Thyroid function and Hashimoto’s disease.

We’ll discuss how iodine can be both beneficial and dangerous to your Thyroid health, what symptoms may signal the presence of Hashimoto’s disease and an underactive Thyroid, and we’ll also take a look at what exactly it means when the Thyroid’s function becomes impaired due to the development of Hashimoto’s disease.

An Overview Of Hypothyroidism And Hashimoto’s Disease

The Thyroid gland has a shape that most people associate with the shape of a butterfly. This gland is responsible for the production of hormones that assists with regulating metabolism, as well as some other functions in the body.

The hormone production of the Thyroid gland is regulated by Thyroid Stimulating Hormones, which is secreted by the pituitary gland in the brain. Hashimoto’s disease is a condition that has a direct effect on the Thyroid gland and causes an impairment with the function of this gland to develop1.

This disease is an autoimmune condition, which means the immune system sends antibodies mistakenly toward the Thyroid gland. When this occurs, the Thyroid gland’s tissue is attacked as if the tissue is pathogenic of nature.

Inflammation is the result of this reaction, as well as damage to the Thyroid gland.

Symptoms Associated With Hashimoto’s Disease

During the early stages of Hashimoto’s disease, a patient may not experience any obvious symptoms that may signal the fact that their Thyroid gland is being targeted by their immune system.

As inflammation develops and damage is dealt with the Thyroid gland, however, symptoms associated with Hypothyroidism tend to develop. Hypothyroidism is a relatively common condition, with Hashimoto’s disease being one of the primary causes behind the condition.

Patients diagnosed with Hypothyroidism have a Thyroid gland that is unable to produce enough hormones to support overall cellular metabolism in the patient’s body.

There is a number of different symptoms that a patient may start to experience as the level of Thyroid hormones being produced start to become reduced. In the majority of patients, some of the first signs that they are developing Hypothyroidism include an increase in their body weight.

This is because Thyroid hormones play a crucial role in metabolism, including fat distribution and the uptake of food. Most patients who develop Hypothyroidism also tend to experience fatigue on a regular basis, as well as an overall feeling of being exhausted and weak2.

In addition to the above-mentioned symptoms, a patient may also experience a reduction in their sweating, become more sensitive to cold temperatures, experience a shortness of breath following physical activity, and they may notice that their pulse is slower than normal.

High blood pressure levels are also relatively common amongst patients who suffer from Hypothyroidism.

It should also be noted that mental impairment, which may include poor memory function, a slower thinking process, changes in speech, and improper concentration, can also develop in patients with this particular Thyroid disorder.

What You Should Know About Iodine Intake And The Thyroid Gland

Iodine is considered a nutrient that the body needs to perform certain functions, with the primary purpose of iodine being the role it plays in the production of Thyroid hormones. The human body is unable to produce iodine by itself; thus individuals should always ensure they obtain an adequate supply of this chemical element from their daily diet3.

Since iodine plays a crucial role in the functionality of the Thyroid gland, it becomes obvious that we need to consume foods that contain iodine daily in order to support this gland. Unfortunately, things get quite complicated when we look at iodine intake and the Thyroid gland.

An adult person should ideally consume enough food that can provide them with roughly 150 mcg of iodine on a daily basis. Pregnant women are recommended to increase their daily intake of iodine to 220 mcg per day, and breastfeeding women are advised to consume 290 mcg of iodine daily4.

The complex relation between iodine intake and Thyroid function occurs when we look at iodine deficiencies and, of course, excessive iodine intake. When a lack of iodine exists in a particular individual’s daily diet, it is obvious to think that their Thyroid will produce less hormones, which is perfectly correct.

When looking at excessive intake of iodine, the initial thought would be that more iodine should equal more Thyroid hormones, but, in reality, the opposite is true.

While a sudden increase in iodine intake amongst patients with Hypothyroidism may lead to temporary Hyperthyroidism, excess iodine in the human body can cause the Thyroid gland to become impaired5.

This is mostly due to the fact that inflammation occurs as the gland becomes overworked, adding more stress and, eventually, causing an autoimmune reaction in the patient’s body.

Iodine Restriction And Hashimoto’s Disease

When a patient is diagnosed with Hashimoto’s disease, it is important for the patient and their physician to consider particular issues in their body and daily lives that could be contributing to the condition.

Numerous studies have been conducted to identify methods that can be utilized to assist with potentially reducing the damage dealt with the Thyroid gland by Hashimoto’s disease, as well as to assist with improving the production and secretion of Thyroid hormones.

For example, one study by the GENLAB Medical Diagnostics and Research Laboratory in Turkey found that anaerobic exercise at a high-intensity level can provide a significant boost in Thyroid hormones6.

One particular method for providing an alleviation in the symptoms and particular actions caused by Hashimoto’s disease might lie within a diet that restricts iodine intake for a certain period of time.

Iodine restriction has not been proven to produce improvements in Hashimoto’s disease directly, as it has been found that this particular technique helps to improve Thyroid hormone secretion in patients who suffer from Hypothyroidism even when Hashimoto’s disease is not the cause behind the patient’s Thyroid disorder. Still, iodine restriction needs to be considered as a potential option to assist with improving Thyroid hormone production and secretion, as well as to help to alleviate the symptoms a particular individual may be experiencing due to Hypothyroidism.

One study7 by the Yonsei University College of Medicine in Korea explains their findings when iodine restriction diets are provided to a group of participants who suffer from Hypothyroidism. Amongst the participants, all cases of Hypothyroidism were linked to Hashimoto’s disease as the particular cause.

While this study was relatively small, with only 45 participants involved, it still provided more insight into methods that can be used to possibly address Hashimoto’s disease and Hypothyroidism, and opened up an opportunity for further research to be conducted.

The 45 participants were divided into two different groups. One group were given a diet where iodine restriction was placed, while the other group was not provided any restrictions on iodine-rich foods they may consume during the study period.

Several tests were conducted on each participant to monitor the levels of Thyroid Stimulating Hormone, T3 and T4 hormones in their bloodstream. These tests were performed at the beginning of the study, as well as after a three-month period. Iodine levels in urine of all patients were also tested, along with the blood tests utilized to determine Thyroid hormone levels in their bodies.

The results were quite impressive. Less than 50% of the participants who were chosen to be part of the group where no iodine limitations were placed on their diet achieved a euthyroid state after the three-month period (euthyroid is a state where levels of Thyroid hormones and Thyroid Stimulating Hormones are considered normal).

When the scientists behind the study conducted these tests on the group that was requested to limit their iodine intake, an impressive 78.3% of the entire group was able to recover from their Hypothyroidism condition and achieve a euthyroid state. 

It was also found that patients who were able to achieve a euthyroid state had lower levels of both Thyroid Stimulating Hormones in their blood and a lower concentration of iodine in their urine, when compared to those individuals who did not recover from their Hypothyroidism.

While further research is still needed to provide more accurate data on this experiment, the conclusions made by this study already provides individuals suffering from Hashimoto’s disease and Hypothyroidism new hope into treating their condition.

A simple restriction in iodine intake, in this case, might be beneficial and assist with restoring the optimal functionality of the Thyroid gland.

Treatments For Hashimoto’s Disease

Metabolism is vital for the human body’s overall well-being, and Hashimoto’s disease can put a heavy burden on the body’s ability to maintain a healthy metabolism properly. When Thyroid hormones become low in the bloodstream, a patient may start to suffer from any number of symptoms associated with Hypothyroidism, which can cause a significant amount of problems in their life.

The good news is that there are effective treatment options available that can assist with addressing the particular effects that Hashimoto’s disease has on the Thyroid gland, and, of course, to help reduce the severity of the symptoms a patient is experiencing.

Most commonly, the aim of treatment will be to increase Thyroid hormones in the patient’s body first. This will allow for the particular parts of the body that depends on these hormones to regain their ability to function correctly. Levothyroxine sodium is a common medication used to treat Hypothyroidism, and is often prescribed to a patient for their entire lifetime, following the diagnosis of Hashimoto’s disease or any other particular cause of Hypothyroidism.

It should be noted that the dosage and timing of each dose will make a big difference into whether or not the use of synthetic hormones to replace those that the Thyroid gland is unable to make will result in the desired outcomes.

Low doses of Levothyroxine are usually given to patients when they are first going on treatment8, but it should be noted that most patients need one or more adjustments to the dosage of Levothyroxine they take before they achieve that perfect dosage that helps to restore Thyroid hormone levels without causing any problems.

Most patients are screened every six weeks when they first go on Levothyroxine medication, and their dosage is then adjusted based on the results of the blood tests after they have taken a particular dosage for the past six weeks. Doctors may switch the patient to natural desiccated thyroid such as Armour Thyroid or WP Thyroid.

When a physician finds the right dosage for the patient, then visits will become less regular – sometimes only once a year to check up on the patient and ensure the dosage is still correct, and that they are not experiencing a worsening of their condition.


Patients who have been diagnosed with Hashimoto’s disease tend to develop Hypothyroidism as the disease progresses.

Iodine is a popular topic amongst medical publications describing Hypothyroidism and Hashimoto’s disease, but the connection that exists between iodine intake and this condition is complicated.

While the intake of iodine is important for the adequate production of Thyroid hormones, the opposite is true when iodine intake becomes elevated.

In turn, the excess iodine can cause further impairment of Thyroid function, leading to a worsening of the symptoms associated with hypothyroidism and a further reduction in the secretion of Thyroid hormones in the bloodstream.


1 Hashimoto’s Thyroiditis. WebMD. https://www.webmd.com/women/hashimotos-thyroiditis-symptoms-causes-treatments#1

2 Hypothyroidism: Symptoms. PubMed Health. https://www.ncbi.nlm.nih.gov/pubmedhealth/PMHT0022777/

3 Iodine. WebMD. https://www.webmd.com/vitamins-supplements/ingredientmono-35-IODINE.aspx

4 Iodine. National Institutes of Health. https://ods.od.nih.gov/factsheets/Iodine-Consumer/#h2

5 Hye Rim Chung. Iodine and thyroid function. Annals of Pediatric Endocrinology & Metabolism. 31 March 2014. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4049553/

6 Multiple Authors. Exercise intensity and its effects on thyroid hormones. U.S. National Library of Medicine. 26 December 2005. https://www.ncbi.nlm.nih.gov/pubmed/16380698

7 Multiple Authors. The Effect of Iodine Restriction on Thyroid Function in Patients with Hypothyroidism Due to Hashimoto’s Thyroiditis. Yonsei Medical Journal. 2003. https://www.ncbi.nlm.nih.gov/pubmed/12728462

8 Stephanie L. Lee. Hashimoto Thyroiditis Treatment & Management. Medscape. 2 March 2018. https://emedicine.medscape.com/article/120937-treatment

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