We are exposed to potentially harmful chemicals and toxic substances on a daily basis. The workplace, public spaces, and even the home harbor numerous substances that can have a negative impact on wellness. Healthy individuals typically have a robust enough system to handle this regular exposure to toxins. However, a condition known as multiple chemical sensitivity or MCS may chronically reduce chemical tolerance. The combination of increased chemical sensitivity and near constant exposure can notably disrupt thyroid function. Understanding the importance of healthy thyroid function and the impact of MCS on the thyroid may lead to greater thyroid care.
What You need to Know About the Thyroid
The thyroid is a small gland located in the neck that influences numerous bodily functions. Some describe this essential system as the body’s gas pedal because it controls the activity level of cells and tissues throughout the body. This regulatory action is made possible through the production of hormones. Thyroid hormones relay messages to and from the many systems of the body to coordinate processes, regulate speed, and ensure proper bodily function. As the presence of specific thyroid hormones increase, physiological activity accelerates. Conversely, a deficit of thyroid hormone results in a slowing of bodily activity.
The Impact of Chemicals on the Thyroid
The endocrine system is responsible for regulating hormone activity throughout the body. The individual components that make up the endocrine system, including the thyroid, are particularly sensitive to chemicals and toxins called endocrine disruptors. These substances are found in many household products, processed foodstuffs, and many medications. Unfortunately, even minor exposure to harmful endocrine disrupting chemicals contained in these substances can disturb thyroid function and contribute to the development of thyroid disease – learn more about endocrine disruptors here. As such, individuals with multiple chemical sensitivity (MCS), who have an increased sensitivity to toxins and chemicals, may have an exceptionally higher risk of suffering from thyroid related dysfunction.
Dysfunction of the thyroid can have far reaching effects on overall health. The most common form of thyroid disruption is hypothyroidism or slowed thyroid function. Impeded thyroid activity causes a decline of metabolic function, which is accompanied by symptoms such as fatigue, brain fog, depression, and weight gain. There are several potential causes of hypothyroidism including poor communication between systems, inhibited hormone production, and reduced hormone receptivity. Each of these factors may be triggered by greater exposure and/or increased sensitivity to endocrine disrupting chemicals.
Making Sense of Multiple Chemical Sensitivity
Multiple chemical sensitivity (MCS), also known as toxicant-induced loss of tolerance (TILT), is a multi-organ condition that greatly increase an individual’s sensitivity to common chemicals. MCS may develop abruptly and at any age causing patients to unexpectedly react poorly to substances that were previously tolerable.
Common triggers of MCS include: cookware, orthodontics including braces and retainers, medical implants, contact lenses and their solution, fragrances, cleaning products, jewelry or other metals that contact the body, vehicle exhaust, flame retardants often found in furniture and home goods, mold, smoke, adhesive fumes, plastics, and much more. A more complete list of common chemical aggravators can be found here.
In addition to material triggers, there are several factors that may put you at risk for developing MCS. Rarely does this condition develop without one or more of the following contributors being present in the patient:
- Acute exposure to high levels of toxins
- Extended or chronic exposure to moderate or low level of toxins
- Inhibited elimination of toxins from the body
- Deficiency of nutrients used in detoxification (vitamin D, omega-3 fatty acids, etc.)
- Dysbiosis or other gastrointestinal issues
- Genetic factors
- Reduced antioxidant levels specifically glutathione
When exposed to one or more aggravating substances, those with MCS may experience a wide range of symptoms. Common allergic reactions associated with MCS include weakness, fatigue, memory loss, dizziness, anxiety, nausea, respiratory issues, joint pain, and inflammation. A person’s response to chemicals and toxins is dependent on how their body expresses inflammation and immune dysregulation. Because individuals with MCS are naturally more sensitive to chemical substances, they may experience severe symptoms even if other individuals exposed to the same environment do not.
The Relationship Between Thyroid Dysfunction and MCS
MCS is caused by chronic immune disruption, which is associated with greater risk of developing other chronic illness. A 2014 study titled Evaluation of suffering in individuals with multiple chemical sensitivity, found that MCS is frequently found in conjunction with one or more chronic illnesses such as fibromyalgia, chronic fatigue syndrome, irritable bowel syndrome, and thyroid disease in the form of hypothyroidism.
It is argued that due to the increased toxicity of the modern world, the number of diagnosed cases of MCS in the past ten years has increased by more than 300 percent with self-reported cases increasing 200 percent. One study composed of nearly 1,600 individuals found that over 12 percent of the participants reported hypersensitivity to commonly used chemicals. This increase in MCS may also contribute to greater occurrence of thyroid disease.
Studies show that increased exposure to environmental synthetic chemicals can impact thyroid function by reducing levels of circulating thyroid hormone and blocking thyroid hormone receptors. Furthermore, heightened sensitivity to chemicals may also act as a trigger for autoimmune thyroid disease such as Hashimoto’s Thyroiditis and Graves’ disease.
Thyroid patients who develop MCS may experience a dramatic worsening of their condition. As sensitivity to chemicals increases, new symptoms may develop, existing symptoms may become more intense, and sudden thyroid-related flare ups may occur. Greater chemical sensitivity may also require that a patient’s dosage of thyroid hormone replacement medications be increased to make up for the decline in thyroid functionality.
Protect Your Thyroid from Chemical Disruption
Studies have not found a direct link between thyroid disease and MCS. However, research shows that those with MCS often have thyroid hormone imbalances, resulting in thyroid dysfunction. Additional research is needed to confirm the mutual influence of MCS and thyroid disease but presently it appears that the two are indeed connected. Furthermore, it is well documented that exposure to endocrine disrupting chemicals can have a dramatic effect on thyroid function. The impact of these substances is only heightened among those with MCS. If chemical sensitivity is a factor in your life, it is important that you take proper care of your thyroid and protect yourself from potentially disruptive chemicals and toxins.
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