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Is Exposure to Mercury the Cause of Your Hashimoto’s?

Is Exposure to Mercury the Cause of Your Hashimoto’s?

Hashimoto’s thyroiditis is an autoimmune thyroid disorder that can have a significant effect on overall wellness. The development of Hashimoto’s is influenced by many factors. Recently, it was discovered that exposure to mercury also may be a significant contributor. Unfortunately, many are not aware of or overlook the important connection between mercury and Hashimoto’s. Only by understanding Hashimoto’s and the influence mercury has on its development can we more effectively treat autoimmune thyroid disease.

A Brief Overview of the Thyroid

To discuss Hashimoto’s, we must first have a good understanding of the thyroid. The thyroid gland is a small organ located in the neck that is responsible for producing several hormones. These hormones have many responsibilities with perhaps the most important being the regulation of metabolic activity. Irregular thyroid function can cause symptoms and malfunction throughout the body. One of the leading causes of thyroid dysregulation is Hashimoto’s thyroiditis.

Learn more about the thyroid gland here.

What is Hashimoto’s Thyroiditis?

Hashimoto’s thyroiditis is an autoimmune thyroid disorder that causes the body’s own immune system to incorrectly identify healthy thyroid tissue as a threat. After labeling the thyroid as dangerous, the immune system releases thyroid antibodies to attack the tissue. Over time the gland becomes increasingly damaged, thyroid function declines, and symptoms of hypothyroidism develop.

Additionally, as thyroid tissue is destroyed, the previously contained hormones are suddenly released resulting in symptoms more consistent with hyperthyroidism. This infrequent hyperthyroid state is known as Hashitoxicosis.

Those with Hashimoto’s may experience symptoms consistent with both hypothyroidism and hyperthyroidism. Patients may suffer from some or all of the following symptoms at varying degrees of intensity and frequency: sluggishness, fatigue, muscle or joint pain, low libido, hair loss, anxiety, jitteriness, weight fluctuations, and insomnia.

Get a full list of thyroid disease symptoms here.

The Link Between Mercury and Hashimoto’s

Recent research suggests that exposure to mercury may negatively affect thyroid function while also encouraging the development of Hashimoto’s.

Mercury is a naturally occurring heavy metal that is toxic to the body at low concentrations. Mercury also has a low excretion rate meaning that harmful accumulation and buildup of mercury is possible even from minimal exposure.

Most people are unwittingly exposed to mercury on a daily basis. The harmful mineral is found in many items including cosmetics, pesticides, fish, and dental fillings. Furthermore, mercury released into the air through coal burning or other polluting activity may travel and accumulate into our water supply.

How Does Mercury Encourage Hashimoto’s?

Exposure to mercury can promote the development of Hashimoto’s in a variety of ways. Some of the most notable are discussed below.

Mercury Inhibits Hormone Conversion and Production

Iodine is a chemical readily used by the thyroid to produce hormones. Because mercury and iodine are chemically similar, the thyroid is prone to acquiring the toxic metal. Unfortunately, the presence of mercury in the thyroid may dysregulate conversion of inactive thyroid hormone T4 into the active form T3. This can worsen or encourage the development of Hashimoto’s. Mercury may also deplete the body’s supply of selenium. Selenium is an important nutrient used in the synthesis of thyroid hormone.

Mercury Increases Thyroid Antibody Count

Studies show a correlation between elevated mercury values in the bloodstream and the total number of thyroid antibodies. Increased thyroid antibody count and activity is a leading factor in the development of Hashimoto’s. An increase in thyroid antibody values is also highly indicative of Hashimoto’s – though it is possible to have Hashimoto’s without elevated antibodies.

Mercury Promotes Cell Damage

Studies suggest that cell damage caused by mercury may encourage autoimmune activity. Furthermore, it is theorized that the immune system has a more aggressive response to mercury than other toxins. Therefore, when mercury settles into the thyroid, greater damage done to the thyroid gland due to the intensity of the autoimmune response.

Testing for Hashimoto’s and the Presence of Mercury

Testing for Hashimoto’s requires an accurate assessment of thyroid function. At minimum this should include testing of thyroid stimulating hormone (TSH), T4, T3, and Reverse T3. However, it is also essential that thyroid antibodies, specifically thyroglobulin antibody (TgAb) and thyroid peroxidase antibody (TPOAb), be tested. Increased values of TgAb and TPOAb is highly indicative of autoimmune thyroid disease.

Get a FREE sample lab slip here.

If mercury toxicity is suspected, additional testing must be done. Fortunately, most mercury tests are not complicated and often only require a sample of blood, urine, or hair. Evaluating the amount of mercury in the system can inform future protocols and allow for more effective treatment

How to Effectively Remove Mercury

If a Hashimoto’s patient exhibits elevated values of mercury it is essential that steps be taken to limit further exposure and reduce the amount of mercury in the body. This can be done in multiple ways.

Dietary Improvements

Consumption of mercury-bearing foods can increase the amount of mercury inthe body. Some examples of common mercury-carrying foods include ahi tuna, bigeye tuna, king mackerel, shark, and other larger fish. As such, it may be beneficial to limit intake of fish and other seafoods.

Removing Dental Amalgams

Amalgams that contain mercury steadily release small amounts of the toxic metal, which can accumulate in the thyroid over time. One study found that removal of mercury-based dental amalgams prompted a decrease in not only mercury values but also a reduction in the number of thyroid antibodies. However, it is important to note the improper removal of amalgams can cause mercury values to temporarily spike thereby triggering greater immune malfunction and exacerbate Hashimoto’s.

Chelation Therapies

Chelation is an effective but also potentially damaging approach to improving the body’s toxic load. Chelators such as NAC, alpha lipoic acid, and chlorella, bind to toxic agents such as mercury allowing them to be safely excreted later. However, inappropriate use of chelators can actually worsen symptoms of toxicity and cause nutrient depletion. These issues can be avoided by ensuring the body has adequate glutathione and other antioxidants to aid the excretion process. If considering chelation, be sure to speak with an expert before using them.

Making Sense of Mercury and Hashimoto’s

Hashimoto’s is a highly impactful condition that involves a great many factors. Mercury is one element that is easy to overlook yet may strongly contribute to the development and continuation of Hashimoto’s.

If you have been diagnosed with Hashimoto’s or other form of autoimmune illness, speak with your doctor about testing for toxic metals like mercury. With a strong understanding of the relationship between mercury and Hashimoto’s, you are better equipped to combat and resolve autoimmune thyroid disease.


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