Which Toxins Affect The Thyroid And How To Avoid Them
Americans as a whole suffer from thyroid disorders at an unprecedented rate, so let’s consider the upstream causes, specifically, which toxins affect the thyroid. Levothyroxine, used to treat thyroid disorders, is one of the most commonly prescribed drugs in the United States, with over 21 million prescriptions being filled each year. Levothyroxine is a synthetic form of thyroid hormone. It is used to treat an underactive thyroid gland (hypothyroidism) and prevent goiter (enlarged thyroid gland).1
Why Are So Many Americans Using Levothyroxine?
With around 7% of the United States population using levothyroxine, it’s important to ask why. While there are multiple factors that contribute to thyroid dysfunction, toxins are at the forefront. When toxins affect the thyroid, it is unable to properly regulate metabolism. This leads to a variety of health issues including obesity and metabolic syndrome.2
The thyroid is the canary in the coal mine. In the past, miners would bring a canary with them when they entered a coal mine because canaries are extremely sensitive to toxins. If the canary died due to toxic gasses within the coal mine, the miners knew they had to quickly exit the mine. In a similar fashion, thyroid tissue is extremely sensitive to toxins. Once thyroid dysfunction is present, health complications from autoimmune conditions and hormone problems quickly follow.
Which Toxins Affect The Thyroid – Heavy Metals
Heavy metals such as mercury, lead, and cadmium accumulate in the thyroid gland and interfere with its ability to produce hormones. Exposure to these metals leads to hypothyroidism.3
Which Toxins Affect The Thyroid – Mercury
Of all the heavy metals, mercury causes the most damage to the thyroid. When mercury enters the body, it accumulates in various organs and tissues, including the hypothalamus, pituitary, and thyroid gland.
As mercury enters the brain and accumulates in tissues like the pituitary-hypothalamus, hormone function throughout the body becomes disrupted. This is because the hypothalamus is this hormone control center. Think of it this way, the hypothalamus is like the airport control tower. If the airport control tower isn’t functioning, chaos would ensue, as pilots wouldn’t know when to land or take off. When the hypothalamus is loaded with toxic mercury, it is unable to tell the thyroid how much thyroid hormone to produce.
This is exactly what happened to me, as mercury from dental fillings and contact lens solution accumulated in my brain and made me sick. Read more about my story and how I discovered that mercury toxicity and other stressors were responsible for my illness.
Another one of the main ways that mercury affects the thyroid is by interfering with the production of thyroid hormones. The presence of mercury inhibits the conversion of inactive thyroid hormone T4 into its active form, T3.4
The conversion of T4 to T3 is a crucial process that takes place in the liver and gut. The liver is the main organ responsible for converting T4 to T3. It is responsible for approximately 60% of the conversion, while the remaining 40% takes place in the gut. This conversion process is facilitated by enzymes called deiodinases, which are present in both the liver and gut.5
The liver and gut play a vital role in maintaining thyroid hormone balance and ensuring that T3 levels remain within normal limits. Mercury toxicity causes damage to these organs, leading to an imbalance in thyroid hormones.6
Mercury also impacts the thyroid by disrupting the function of iodine, an essential nutrient required for proper thyroid hormone production. Studies have shown that exposure to mercury decreases levels of iodine in the body, leading to thyroid issues.7
Furthermore, research reveals that mercury increases TSH levels. This disruption results in abnormal levels of thyroid hormones, leading to symptoms such as fatigue, weight changes, and mood disorders.8
How Mercury Affects Selenium
Compounding on top of that, mercury negatively affects the function of selenium. Selenium is a mineral that is essential for thyroid health and function. It acts as an antioxidant, protecting the thyroid gland from damage caused by free radicals. Additionally, selenium plays a crucial role in the conversion of T4 to T3. Studies have shown that individuals with low levels of selenium in their body are more likely to develop hypothyroidism.9
On the other hand, excessive intake of selenium can also have adverse effects on the thyroid gland. Too much selenium inhibits the production of thyroid hormones. Therefore, it is essential to maintain a balance and consume selenium in recommended amounts. For adequate selenium intake, consume two Brazil nuts per day.10
Selenium has such a strong affinity for mercury that it pulls it into cells. While adequate levels of selenium are crucially important for thyroid health, they also increase cellular mercury accumulation. This is one reason why it is so important to force mercury out of the body if we want to regain ideal thyroid function.
Reducing Exposure To Mercury
To reduce exposure to mercury and protect thyroid health, it is recommended to limit consumption of fish and seafood known to be mercury bioaccumulators. Additionally, remove silver amalgam dental fillings, as they contain mercury. Ideally, opt for organic and locally grown produce to reduce exposure to pesticides which often contain mercury. Finally, avoid getting tattoos, as the ink contains mercury and many other heavy metals.11
Removing Mercury And Other Heavy Metals From The Body
Detox is a cellular issue. I developed my 5Rs to facilitate the detoxification of heavy metals and other toxins from the cells. By focusing on cellular detoxification, we directly target the upstream reason for thyroid dysfunction.
R1 is all about removing the source of toxicity from your life. If you are still being poisoned by mercury from dental fillings or another source, mercury will continue to bioaccumulate.
R2 focuses on regenerating the cellular membrane. Mercury causes cellular membrane inflammation. When cellular membrane inflammation is present, nutrition cannot enter cells and waste products cannot leave cells.
Additionally, cellular membrane inflammation changes the shape of hormone receptors. When this happens, hormones like thyroid hormone are unable to send their message into the cell. Even if there are sufficient quantities of T3 circulating throughout the blood, active thyroid hormone is unable to regulate cell metabolism. This is known as thyroid hormone resistance. Toxin-induced cellular membrane inflammation is the reason for hormone resistance across the board including insulin, estrogen, testosterone, and leptin resistance.
R3 is all about restoring cellular ATP production. ATP is the energy cells need to thrive. To restore ATP production, we must open up cellular detox pathways and upregulate cellular function. Sufficient cellular ATP allows for the production of glutathione, a strong antioxidant that aids in cellular detoxification. When the cell functions as it should, toxins like mercury can finally be excreted by the cell.
R4 involves down regulating cellular membrane inflammation. As toxins are removed from cells, it seems logical that cellular membrane inflammation would downregulate naturally. However, a complex feedback loop called the NO/ONOO cycle maintains cellular membrane inflammation. We use specific nutraceuticals to finally put an end to this inflammation.
R5 comes down to restoring methylation through the use of methyl donors. Heavy metals sabotage methyl groups required for methylation. Methylation is required for detoxification, removing toxic hormone metabolites, and optimizing epigenetic regulation. Proper methylation turns on ideal genes and shuts off bad genes that were triggered by toxins.
Chelating agents also play a crucial role in the detoxification process, particularly when it comes to heavy metal removal. These powerful compounds, such as DMSA, DMPS, and ALA, contain double thiol groups that have the ability to strongly bind to heavy metals after they are removed from cells and facilitate their excretion from the body.12 13 14
However, this process alone is not enough to completely eliminate heavy metals from the body. This is where substances called gut binders come into play, ensuring that heavy metals are effectively removed from bile and eliminated from the body. Consistent use of both chelators and binders is necessary for successful detoxification, as it can take years to fully rid the body of accumulated heavy metals.15 16
Which Toxins Affect The Thyroid – Pesticides
Certain pesticides contain chemicals that disrupt the normal functioning of the thyroid gland. These include organochlorines and organophosphates like Roundup, which have been linked to an increased risk of hypothyroidism.17
In addition to their direct effects on the thyroid gland, pesticides also indirectly affect the thyroid by disrupting the production and conversion of important hormones. For example, some pesticides have been found to interfere with the production of T4. This is one reason why so many people are on the exogenous T4, Levothyroxine.18
Furthermore, pesticides disrupt the endocrine system, which plays a crucial role in regulating hormone production and balance in the body. This disruption affects the thyroid gland and other hormone-producing organs, leading to a variety of health issues.19
To reduce exposure to pesticides and protect our thyroid health, it is important to choose organic produce whenever possible and avoid using pesticides in and around our homes.
Which Toxins Affect The Thyroid – BPA
Bisphenol A (BPA) is a chemical commonly found in plastic products and leaches into food and water. Studies have shown that BPA interferes with the production of thyroid hormones, leading to a condition known as subclinical hypothyroidism. This is a mild form of hypothyroidism where the thyroid hormone levels are slightly lower than normal, but not enough to cause obvious symptoms.20
BPA disrupts the function of the thyroid gland by mimicking the structure and activity of estrogen. This leads to imbalances in other hormones and disrupts the body’s endocrine system as a whole.21
Which Toxins Affect The Thyroid – Cosmetics
Some cosmetics contain toxins that affect the thyroid. One such toxin is Benzophenone-2 (BP-2), a chemical commonly used in sunscreens, moisturizers, and other personal care products. BP-2 mimics the function of thyroid hormones and binds to thyroid hormone receptors, leading to hormonal imbalances and thyroid disorders.22
Similarly, Octyl-methoxycinnamate (OMC) is another commonly used chemical in sunscreens, lip balms, and other cosmetics that has been linked to thyroid dysfunction. OMC also mimics the function of thyroid hormones and interferes with their production.23
Which Toxins Affect The Thyroid – Phthalates
Phthalates, commonly used as softeners in plastic products, have been shown to alter the levels of thyroid hormones. Once inside the body, phthalates bind to thyroid hormone receptors and disrupt the normal function of the thyroid gland. This leads to a decrease in thyroid hormone production and an increase in levels of thyroid-stimulating hormone (TSH) which often indicates an underactive thyroid.
Aside from disrupting the production of thyroid hormones, phthalates have been found to increase the activity of enzymes that break down these hormones. This means that even if the body is producing enough thyroid hormones, they are quickly broken down and rendered ineffective by the presence of phthalates. This results in symptoms of hypothyroidism, even when thyroid hormone levels appear normal on blood tests.24
Studies have also shown that exposure to phthalates during pregnancy affects the developing fetus’s thyroid function. This leads to developmental and cognitive issues later in life.25
Which Toxins Affect The Thyroid – PBDEs
Another chemical commonly found in plastic products is polybrominated diphenyl ethers (PBDEs), which are used as flame retardants. PBDEs are used in a variety of consumer products such as electronics, textiles, and plastics. Studies have shown that exposure to PBDEs leads to disruptions in thyroid hormone levels.26
PBDE exposure decreases the production of thyroid hormones. This is due to the ability of PBDEs to interfere with the enzymes responsible for producing these hormones. PBDEs also affect the way in which thyroid hormones are metabolized in the body, leading to changes in their levels and functions.27
PBDEs have been shown to disrupt the signaling pathways of thyroid hormones. Exposure to PBDEs has been associated with increased levels of inflammation in the thyroid gland, which contribute to the development of autoimmune thyroid diseases.28
Which Toxins Affect The Thyroid – Perchlorates
Perchlorates are used in rocket fuel and easily contaminate drinking water. Perchlorates have been found to block the absorption of iodine. This leads to hypothyroidism and other thyroid-related issues. In addition, perchlorates also interfere with the function of the thyroid gland itself, leading to a decrease in hormone production.29
Groundwater is the primary source of irrigation water for agriculture in many regions. Perchlorates from rocket fuel or fireworks debris leaches into the groundwater. This contaminated water is then used to irrigate crops.30
If you consume spices, cucumber, avocado, leek, spinach, sweet potatoes, tomato, onions, peppers, and lettuce that was grown in the Southwestern part of the United States, there’s a strong possibility it contains perchlorates, even if it is certified organic.31
Which Toxins Affect The Thyroid – Fluoride
Fluoride interferes with the normal functioning of the thyroid gland by blocking the uptake of iodine and disrupting the production of hormones. Fluoride interferes with enzymes that are necessary for thyroid hormone synthesis.32
Which Toxins Affect The Thyroid – PFAS
Studies have shown that exposure to PFAS disrupts the normal functioning of the thyroid gland. These chemicals interfere with the production, transport, and metabolism of thyroid hormones. Moreover, PFAS affect the thyroid by binding to thyroid hormone receptors and blocking their normal function.33
Read more about the toxic effects of PFAS.
Improve Thyroid Health – Eat A Healthy Diet With Iodine And Selenium-Rich Foods
Eating a balanced diet with plenty of iodine-rich foods such as seaweed, dairy, and seafood support thyroid health. Also consider taking Lugol’s iodine solution to ensure sufficient iodine intake. As mentioned earlier, Brazil nuts are the best source of selenium, but other nuts, seeds, grass-fed meat, and grass-fed dairy also contain this element.35 36
Which Toxins Affect The Thyroid And How To Avoid Them
Now that you know which toxins affect the thyroid, it is important to limit exposure by avoiding products and environments that contain them. Additionally, we must upregulate cellular pathways, put an end to cellular membrane inflammation, and improve cellular detox functions to remove these toxins from the body. By being aware of potential threats and taking proactive measures, you can help protect your thyroid from harmful toxins.
Read more about thyroid disease.
References
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