How Hypothyroidism Affects the Entire Body

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The deep interconnectivity of the body means that the areas directly impacted by poor thyroid function can reverberate and damage other, seemingly unrelated areas.

Hypothyroidism is one of the most common forms of thyroid disease that, like other thyroid conditions, can result in systemic disruption. Understanding thyroid dysfunction and its significant impact on nearly all the body’s systems can lead to improved diagnosis, treatment, and wellness.

What is Hypothyroidism?

The thyroid is responsible for the production and regulation of hormones that influence systems throughout the body.

It is estimated that thyroid disease affects over 20 million Americans with a large percentage of this group being hypothyroid. When the thyroid is incapable of producing the thyroid hormone needed to maintain proper functionality it is considered hypothyroid. Typically, hypothyroidism causes a slowing of bodily function.

The impact of hypothyroidism is widespread and can be seen throughout the body. The following areas are particularly impacted by hypothyroidism. However, the negative effects of thyroid dysfunction are not limited to just these regions.

Blood Sugar Regulation

The pancreas and thyroid are closely related and have significant influence on each other. Reduced thyroid hormone levels can limit pancreatic action resulting in poor glucose absorption in the gut, breakdown of insulin, and glucose insulin interaction. These elements can cause a glucose deficiency, ultimately decreasing cellular energy resulting in physical and mental fatigue.

Bone Health

Those with low levels of thyroid hormone typically have a higher bone density that can cause irregularities in collagen, bone turnover, mineral crystal size, and the structure of the bone itself. The result of these factors is an increased risk of fracture even though the bone has greater density.

Children with low thyroid hormone may experience inhibited bone growth, which can affect the child’s physical development.

Brain and Mood

Thyroid hormones are important for brain growth and tissue retention. Hypothyroidism can contribute to decreased brain size later in life and mood disorders.

A 2012 study published in the Journal of Thyroid Research states that those with a thyroid condition are more likely to develop depression or suffer depressive states than those with normal thyroid levels.

Additionally, one of the most common symptoms of hypothyroidism is brain fog or difficulty thinking clearly. Inflammation and weakening of the blood brain barrier due to limited thyroid hormone availability is typically the cause.

Cardiovascular Health

Arterial function is significantly impacted by thyroid hormone activity. Studies have found an association between low levels of T3 and cardiovascular disease. Hypothyroidism can contribute to low blood pressure and a slower heart rate. This increases the risk of plaque buildup, hardening of the arteries, and heart attack or stroke.

A weakened heart due to poor thyroid prevalence limits the amount of oxygen transported throughout the body. This can make breathing difficult, especially when exercising. Furthermore, the resulting drop in blood flow can cause cooling of the extremities and contribute to hair loss and fungal nail growth.

Cholesterol Balance and Usage

Cholesterol is a necessary component of hormone building, including the construction of thyroid hormones. A lack of thyroid hormones may cause a reduction in fat breakdown while also reducing LDL receptors. Hypothyroid states can delay cholesterol usage and limit the removal of excess cholesterol. This decreased efficiency results in increased levels of triglycerides, and LDL or “bad” cholesterol.

Digestion and Intestinal Wellness

Thyroid hormones facilitate the exchange of information between the brain and gut. Reduced thyroid function can limit this communication, which can cause issues such as constipation, malabsorption, and dysbiosis or an imbalance of beneficial bacteria. Dysbiosis is often involved in the development of yeast or fungal overgrowth.

A thyroid hormone deficit can limit muscle and nerve action that facilitates movement in the esophagus, thereby slowing digestion. Furthermore, low thyroid levels are associated with reduced levels of gastrin. Low gastrin levels may cause heartburn, ulcers, reflux, bloating, and inflammation.

Liver Function

The liver is a leading factor regarding T4 to T3 conversion. Therefore, liver disease can negatively impact active thyroid hormone levels. Interestingly, the thyroid also influences the liver function and its ability to effectively remove harmful substances. A thyroid deficit can inhibit liver activity, which negatively impacts thyroid hormone conversion thereby worsening hypothyroid states.

Metabolism and Energy

Thyroid hormones are critical to metabolic function and regulation. Poor thyroid function means a reduction in metabolic activity, which contributes to weight gain, an inability to lose weight, and fatigue. Hypothyroidism also inhibits the body’s ability to utilize fatty acids meaning that fat cannot be effectively broken down and dispersed as fuel for other cells.

Reproductive System

Women suffering from hypothyroidism frequently suffer from menstrual irregularities, including light, heavy, or missing periods. Poor thyroid levels may also lead to infertility and miscarriage. According to the American Thyroid Association, women are five times more likely to develop hypothyroidism. Therefore, women wanting to get pregnant should have their thyroid function monitored prior to and during pregnancy.

Skin and Hair Health

A common complaint of hypothyroid patients is an inability to tolerate colder temperatures, which can lead to the development of dry and waxy skin. Other changes such as ridged or split nails, swelling, and paling or yellowing skin may occur in more advanced cases of thyroid imbalance. Hypothyroid patients may also experience increased hair coarseness, dryness, and hair loss on the scalp, eyebrows, and body.

Reading the Signs of Hypothyroidism

Because hypothyroidism may cause dysfunction throughout the body, the wide array of symptoms that develop can be misleading and difficult to diagnose. Furthermore, individual symptoms and the intensity at which they occur is different for every patient. Therefore, it is important to be aware of the many different areas impacted by the thyroid in order to properly identify the issue.

With a better understanding of how the thyroid influences various systems and what areas of dysfunction may point to thyroid imbalance one can better recognize thyroid dysfunction and subsequently seek proper treatment.

For more information on proper thyroid function and treatment, read our Thyroid 101 e-book!

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1. The Thyroid is Connected to So Many Parts of the Body. Hypothyroid Mom.

2. How Hypothyroidism Affects The Entire Body. Thyroid Nation.

3. The Effects of Hypothyroidism on the Body. Healthline.