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Is Fluoride a Threat to Your Thyroid Health?

Is Fluoride a Threat to Your Thyroid Health?

Fluoride is a naturally occurring substance that has a long history of use in the United States. You may already have some familiarity with fluoride as the chemical has become a regular inclusion in the water supply of many communities throughout the U.S. In fact, it is estimated that over 66 percent of the U.S. population drinks fluoridated water. The original intent behind adding fluoride to our water supply was to help improve oral health and prevent cavities, especially in children. However, recent research shows that increased intake of fluoride is associated with a higher risk of thyroid dysfunction and may contribute to the development of other health issues. 

The Important Role of the Thyroid

The thyroid is a small butterfly-shaped gland located in the neck. It is an essential part of the endocrine system and impacts the activity of virtually every cell and tissue in the body – learn more about the thyroid gland here. The thyroid does this through the production of various hormones. The most important hormones regarding thyroid function are T4, T3, and TSH.

  • T4 (thyroxine) is the storage form of thyroid hormone that remains inactive until converted to T3.
  • T3 (triiodothyronine) is the active form of thyroid hormone that accelerates bodily function. 
  • TSH (thyroid stimulating hormone) is a signaling hormone produced by the pituitary gland that tells the thyroid when to produce thyroid hormone such as T4 and T3. 

When functioning properly, the thyroid produces an appropriate level of hormones to maintain bodily function healthy bodily function. Some of the areas impacted by thyroid hormones include metabolism, cognitive function, and mood. However, because of its broad influence, disruption of the thyroid can trigger major hormonal imbalances resulting in a wide range of cascading dysfunction throughout the body. 

Hypothyroidism, or slow thyroid function, is the most common form of thyroid disease. The decline in thyroid hormones associated with hypothyroidism causes the entire body to slow resulting in symptoms such as fatigue, brain fog, weight gain, and skin issues. Even minor insufficiencies of thyroid hormone can trigger these and other forms of dysfunction. Therefore, it is important to actively protect the thyroid from harmful substances that may disrupt its activity. 

Get a full list of thyroid disease symptoms here.

How Does Fluoride Disrupt Thyroid Function?

Until 1970, fluoride was widely utilized as a medical treatment to reduce the metabolism of those with hyperthyroidism or an over active thyroid. Studies from the era noted fluoride’s ability to reduce thyroid activity even at small doses. In the modern era, it seems that many have chosen to ignore or have forgotten this critical information.  

According to the Parents of Fluoride Poisoned Children (PFPC) there are over 190 contemporary studies examining the effects of fluoride on thyroid function. Many of these studies suggest that exposure to fluoride can disrupt thyroid function resulting in thyroid disease like hypothyroidism. 

A report made by the National Research Council of the National Academies in 2006, states that fluoride is an endocrine disruptor, meaning that it negatively affects the thyroid itself as well other elements of the endocrine system. Additional research shows that fluoride can block the conversion of T4 to T3, thereby limiting thyroid activity and promoting the development of hypothyroidism. Fluoride may also mimic TSH, thereby interrupting the signals used to regulate proper thyroid hormone production. Worse still, some studies suggest that fluoride can cause damage to thyroid tissue itself, which can cause potentially irreversible thyroid issues. 

The negative effect of fluoride on thyroid function can also be influenced by other factors. Iodine is used in many bodily functions but perhaps the most common use is the synthesis of thyroid hormones like T4 and T3. It is estimated that up to 2 billion people worldwide do not get adequate levels of iodine through their diet to maintain healthy thyroid activity. Research suggests that individuals with iodine deficiencies who also have increased levels of fluoride in their system may be more likely to develop hypothyroidism or other forms of thyroid dysfunction.

How Do I Avoid the Damaging Effects of Fluoride?

Environmental toxins can have a dramatic effect on the endocrine system, and by extension the thyroid. Because of its inclusion in frequently used products such as tea, processed foods, dental products, pharmaceuticals, pesticides, and even our water supply, fluoride is perhaps one of the most commonly encountered thyroid disruptors. 

The ubiquitous use of fluoride can make it difficult to avoid. However, there are steps that can be taken to limit exposure to it. 

Filtering systems are perhaps the best method of limiting fluoride intake. But, because fluoride is a small molecule, many water filtration devices on the market do not effectively remove the harmful chemical. However, there are options, such as those described below, that effectively filter out fluoride and that can help reduce your exposure to it. 

  • Reverse osmosis systems are effective at removing most substances from water. This helps to ensure water is as pure as possible but also removes many beneficial minerals and trace elements found in water. Most reverse osmosis systems also require regular cleaning, but the investment may be worthwhile.
  • Distillation systems are as effective as reverse osmosis but also come with similar drawbacks including removal nutrients. Additionally, distilled water must be restructured before consumed. Unstructured distilled water can sap beneficial nutrients from the body. 
  • Bone char filters and biochar filters with activated coal pull out a great deal of environmental toxins while allowing some trace elements and minerals to remain in the water. This may be the most effective option when considering the amount of effort needed to maintain proper filtration. 

Protect Your Thyroid and Overall Wellness by Limiting Fluoride Exposure

Many studies confirm that fluoride can cause significant thyroidal disruption resulting in severe health issues. Unfortunately, much of the U.S. population is regularly exposed to fluoride through various products and their water supply. Several countries including Germany, Sweden, Japan, and the Netherlands have already halted the practice of fluoridating their water. But the United States continues to do so despite the great deal of research showing fluoride’s association with thyroid dysfunction and increased risk of other health problems. Take charge of your health and protect your thyroid by educating yourself on the effects of fluoride and limiting your exposure to it. 


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