5 Underlying Causes of Thyroid Disease
If you’ve been diagnosed with a thyroid disorder or suspect that your health challenges could be related to a thyroid problem, you’re not alone. According to the American Thyroid Association, 12 percent of Americans will develop a thyroid condition during their lifetime. They estimate that 20 million Americans have some form of thyroid disease and up to 60% of those are unaware that they have a thyroid condition.
Conventional treatment for thyroid disorders typically involves medication, and sometimes even radiation or surgery. While these interventions can be helpful and necessary in certain situations, research suggests that thyroid medication may be overprescribed. These treatments also do not address the root causes of thyroid conditions. In functional medicine, we search for what is actually causing the problem and focus treatment on addressing these root causes.
What would a functional medicine approach to thyroid disorders look like? Here are some potential causes of thyroid disease that we would look for:
Nutrient deficiencies
With the abundance of food available in the US today, you would think nutrient deficiencies would not be a big problem. That is not the case, however. Diets high in processed foods, depleted soils for farming, and gut problems causing reduced absorption of nutrients are some factors that can lead to deficiencies. Some medications can also cause nutrient depletion in the body. While the estimates vary on the actual percentage of Americans with nutrient deficiencies, it is clearly an issue. Common deficiencies include 3 nutrients critical for thyroid function:
Iodine – Iodine is a major component of thyroid hormones and is necessary for thyroid hormone production. The hormone T4 (thyroxine) contains four iodine atoms while T3 (triiodothyronine) contains three iodine atoms. Food sources of iodine include seafood, seaweed, iodized salt, egg yolks, some dairy products, and beef liver.
Selenium – Selenium is an important nutrient in the metabolism of thyroid hormones, as well as in the conversion from T4 to the more active T3. Selenium also functions as an antioxidant and can protect the thyroid from oxidative damage. Food sources of selenium include Brazil nuts, fish, meat, poultry, eggs, sunflower seeds, mushrooms, and brown rice.
Zinc – Zinc is another nutrient that is necessary for the synthesis and conversion of thyroid hormones. It also affects how thyroid hormones bind with their receptors in cells, so it is crucial for the action of thyroid hormones as well. In turn, hypothyroidism can lead to zinc deficiency since thyroid hormones are needed for zinc absorption. Good food sources of zinc include beef, lamb, shellfish, dairy products, pumpkin seeds, and some legumes such as lentils and chickpeas.
Other nutrients important for proper thyroid function include B vitamins, iron, vitamin E, and magnesium. If you aren’t able to get enough of these nutrients through food, supplementation may be helpful. A well-trained functional medicine practitioner can help you determine proper dosing of supplements.
Gut health
Increased permeability in the intestinal lining, often referred to as “leaky gut”, has been shown to be a causative factor in many autoimmune diseases, including autoimmune thyroid conditions such as Hashimoto’s disease and Graves’ disease. Intestinal bacteria help with the conversion of T4 to T3, so dysbiosis in the gut can affect the production of active T3 hormone. Sluggish gallbladder and liver function can prevent hormones from being effectively cleared from the body and affect the levels of thyroid hormones. In turn, impaired thyroid function can have a negative effect on gut health as well. If you are dealing with thyroid issues, improving the health of your gut should be a top priority.
Stress
Too much stress is another known cause of thyroid dysfunction. Chronic stress can affect the axis between the hypothalamus, pituitary gland, and thyroid, which controls the production of thyroid hormones. High cortisol levels affect the production of thyroid hormones and the conversion of T4 to T3. Stress can also trigger or exacerbate autoimmune conditions, including autoimmune thyroid conditions.
Chronic infections
Research has indicated a potential link between certain chronic infections and thyroid disorders. Studies have linked COVID-19 with abnormal thyroid function. Epstein-Barr virus has been shown to be a potential trigger for autoimmune thyroid conditions. Lyme disease may also be associated with some cases of Hashimoto’s and inflammation of the thyroid. If your thyroid condition is not responding to treatment, testing for and addressing chronic infections could be the next step.
Environmental toxins
Certain environmental toxins have been shown to impair thyroid function. These include:
Mold – Mold exposure can affect people in different ways, according to their genetic predisposition and type of mold that they are exposed to. Mold has been shown to cause thyroid dysfunction in some individuals, including Hashimoto’s thyroiditis.
Heavy metals – Heavy metals including mercury, cadmium, lead, arsenic, and aluminum can cause impaired thyroid function. Mercury, for example, can affect the absorption of iodine and bind to selenium, depleting the thyroid of essential nutrients. These metals can also cause oxidative damage to the thyroid.
Fluoride – Fluoride from drinking water appears to affect thyroid function and increase the risk of thyroid diseases. One study showed an increased TSH level in children from high-fluoride drinking water. A high-quality water filtration system can remove fluoride and other toxins from water.
Glyphosate – Glyphosate, the active ingredient in herbicides like Roundup, has been linked in research to increased risk of thyroid conditions including hypothyroidism and thyroid cancer.
If you’ve been dealing with a thyroid disorder and have struggled to find answers, there is hope. Finding and treating the underlying causes of your thyroid dysfunction can restore proper function and improve your symptoms. If a root-cause, functional medicine approach to your condition is your next step, we would love to help! Click here to schedule your free discovery call today.
Sources and References
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