The Ultimate Guide to Understanding Your Thyroid

Nobody can deny the complexity of the human body.

Each and every cell in your body is part of a fascinating network of systems that are communicating with each other.

Like the Chief Operating Officer at a major company – your thyroid gland has a big job to do.

Your thyroid may just be a small gland in your neck, but it influences your entire body. It does this by using hormones to send messages to other cells in your body. 

However, like all of our organs, this important gland is subject to problems and diseases. And lately, we’ve seen an increase in thyroid problems and the negative effects they cause.

Let’s investigate this small but mighty organ, learn how it works, what causes it to malfunction, and how to treat its disorders.

What is the thyroid? Where is it located?

The thyroid is a two-lobed endocrine gland located at the bottom of your neck and under your Adam’s apple. It’s shaped like a butterfly and faces the front of your neck. It contains a network of blood vessels and nerves important for your voice.

When you swallow, the thyroid moves and changes position. Your thyroid is composed of lobules that each contain smaller follicle cells. And these follicle cells contain a large number of sacs that store thyroid hormones.

To find out what these hormones are, keep reading.

How does the thyroid function in the body?

Your brain, via the hypothalamic-pituitary-thyroid axis, communicates with your thyroid using the thyroid stimulating hormone (TSH) after getting a signal from thyrotropin-releasing hormone (TRH) made in the pituitary. Your TSH levels are commonly measured by most doctors. However, TSH from your brain will tell the thyroid what it needs to do, but this doesn’t mean that the thyroid is following the brain’s instructions or that the signal is getting through properly. I’ll explore different types of testing later in this section.

Once TSH communicates with the thyroid, the thyroid releases thyroid hormones. The thyroid makes and secretes two major hormones: triiodothyronine (T3) and thyroxine (T4). About 90% of the thyroid output is in the form of T4, and 10% in the form of T3.  In order for your body to make thyroid hormone it needs two things: thyroglobulin and iodide (a form of iodine).  Iodide is oxidized the follicular cells of the thyroid and then incorporated into tyrosine structures within thyroglobulin.  Then these tyrosine-iodide complexes form T4 and T3 with the help of the TPO (thyroid peroxidase) enzyme.  The three and the four indicate the number of iodine atoms in each molecule. If there are no factors interfering with the process, T4 gets converted to T3 by an enzyme called type 1 deiodinase and takes place in the liver, kidneys, and skeletal muscle. T3 is the active form of the thyroid hormone. T3 and T4 are then secreted into the bloodstream and play a crucial role in many body functions, including your body’s:

• Growth
• Development
• Metabolism
• Protein synthesis
• Body temperature
• Cardiovascular function
• Respiration
• Musculoskeletal system
• Nervous system
• Bone, hard tissues, and skin

Now, there are factors that determine how efficiently the TSH signals get to the thyroid and how efficient the processes such as metabolism occur. Some factors that can interfere with the TSH signal traveling to the thyroid dialogue include:

• Stress
• Inflammation
• Infections
• Toxins
• Nutrient deficiencies

We may be able to determine if this is occurring through thyroid testing. While most doctors only test for TSH, at Arizona Wellness Medicine we test for TSH, free T3, free T4, total T4, total T3, and reverse T3. We also look at autoimmune markers for conditions like Hashimoto’s thyroiditis and Grave’s disease. 

In addition to T3 and T4, the thyroid produces and secretes a hormone called calcitonin. Calcitonin is produced by the C-cells of your thyroid gland and regulates calcium blood levels.

The hormones T3, T4, and calcitonin instruct each cell in the body when to use oxygen and nutrients to undergo metabolism. This is crucial because metabolism is the chemical processes that run your cells’ processes and convert food to energy. 

Your thyroid is controlled by your brain’s hypothalamus and pituitary gland. They communicate with your thyroid as a troubleshooter and tell your thyroid if there are low or high amounts of hormones in the blood. The thyroid then springs into action by connecting with other hormones through interactions like the hypothalamic-pituitary-adrenal axis, or HPA axis. 

How does the thyroid interrelate with other hormones?

The thyroid plays a major function in your everyday life. It does this by communicating with other hormones to complete its functions. One of these interactive communication pathways is the HPA axis.

The HPA axis is made up of the:

• Hypothalamus – located in the brain
• Pituitary gland – located in the brain, at the base of the hypothalamus
• Adrenal glands – located on top of the kidneys

The HPA axis keeps the body in homeostasis but also helps the body respond to stress. For example, if you’re stressed, the HPA axis helps to create and secrete cortisol, a hormone that triggers your fight-or-flight response, into your bloodstream. This happens in the following steps:

1. The hypothalamus secretes corticotropin-releasing hormone (CRH).
2. CRH signals to the anterior pituitary gland to secrete adrenocorticotropic hormone (ACTH) into the bloodstream.
3. ACTH travels to the adrenal glands and prompts the adrenal cortex to secrete cortisol.

The release of cortisol causes changes to help your body deal with stress. Cortisol also helps your body’s immune function and glucose homeostasis. In addition to adrenal hormones like cortisol, your thyroid interrelates with your sex hormones. 

If your body continues to deal with stress for long periods of time, the hormone levels for dehydroepiandrosterone (DHEA) produced in the adrenal gland will drop. DHEA is used to produce sex hormones. Therefore, the drop in DHEA can cause sex hormones progesterone and testosterone to drop. If there’s prolonged stress, estrogen will then drop causing fatigue. 

So, as you can see, your body works in specific ways to regulate your hormone levels and keep everything running smoothly – and your thyroid plays a critical role in it all.

What causes alterations in thyroid function?

There are many things that can alter your thyroid function. This includes: 

• Nutrient deficiencies
• Diet
• Chronic infections
• Inflammation
• Inability to handle toxins
• Leaky gut/intestinal permeability

These alterations can cause stress to your body and may contribute to hormonal imbalances. Through thyroid testing we can identify the root causes of your thyroid problems. We can determine which factors are contributing to your altered thyroid function.

What are common thyroid disorders?

There are different thyroid diseases that can occur depending on the amount of hormones that the thyroid secretes. The two main categories are hypothyroidism and hyperthyroidism.

In hypothyroidism, or low thyroid function, your thyroid can’t make enough hormones for your body to function properly. Typically in hypothyroidism, TSH is high because your brain is releasing hormones and communicating with your thyroid to make hormones. However, your thyroid can’t make enough hormones such as T3 and T4. Some symptoms of hypothyroidism include:

• Weight gain
• Swollen joints
• Depression
• Thinning hair
• Brain fog
• Fatigue

The number one cause of hypothyroidism is the autoimmune disease Hashimoto’s Thyroiditis.  For people with Hashimoto’s, your body’s immune system attacks your thyroid causing your thyroid function to decrease. 

In hyperthyroidism, your thyroid is producing too many hormones. If you have hyperthyroidism, your TSH levels will be low because your brain believes it doesn’t need TSH due to the high amount of thyroid hormones in your body. Your body is overloaded, and this leads to symptoms such as:

• Rapid weight loss
• Anxiousness
• Difficulty sleeping
• Fast heart rate and/or arrhythmias

The most common cause for hyperthyroidism is Graves’ disease, an autoimmune disease where your immune system attacks your thyroid. Your immune system releases antibodies that mimic TSH, causing your body to overproduce hormones. 

To treat these conditions, your doctor may prescribe thyroid medication or supplements to improve your thyroid function. We’ll dive into these treatments next.

Supplements That May Improve Thyroid Function

It’s very important that you ask your functional medicine doctor to test you for nutrient deficiencies. The most common nutrient deficiencies I see in my patients with thyroid disease include:

• Fat Soluble Vitamins: Vitamin D3 and Vitamin A
• Minerals: Iron, Selenium, Magnesium, Zinc, and Copper
• Iodine (too little and too much iodine can affect thyroid function)
• B vitamins: B12, and Folate, Thiamine and Riboflavin (B1 and B2)

Here are some examples of benefits to these supplements: 

• Vitamin D levels tend to be low in my patients with autoimmune diseases leading to poor thyroid function. A supplement may prevent this from occurring.
• Healthy blood cells are made using iron, B12, and folate. Blood cells are used to carry oxygen around your body to provide you with energy. Iron is also needed to convert T4 into T3. 
• Riboflavin and thiamine support your mitochondria which is also needed for energy.

In addition to supplements, you want to be sure you’re not experiencing gut health issues. This will help to ensure that you’re absorbing the supplements properly.  Plus we know 80% of the immune system is located in the gut! 

In some instances, medication is needed for patients with thyroid problems. Here are some common thyroid medication options that your doctor may prescribe.

Different Thyroid Medication Options

As a functional medicine provider, it’s my job to get to the root cause of your thyroid problems. I can treat your thyroid dysfunction using supplements and natural healthcare including lifestyle changes whenever possible. However, thyroid medication may benefit hypothyroid patients while we’re trying to heal their thyroid. The most common medications for hypothyroidism include:

• Levothyroxine: A synthetic form of T4 hormone that’s used to treat hypothyroidism.  This is the most common thyroid medication prescribed by traditional physicians. It comes in many forms including the common brand name Synthroid, but also other brand names such as Levothroid and Tirosint. 
• Liothyronine: A synthetic form of T3 hormone that’s used to treat hypothyroidism when T3 levels do not come up while on just T4.  The common brand name is Cytomel.  Some people do not convert T4 into T3 well enough. 
• Natural desiccated thyroid hormones: these are from porcine thyroid glands and are T4/T3 combinations, and include medications like Armour, Naturethroid, and NP Thyroid. 
• Compounded thyroid medication: your doctor can prescribe precise amounts of T3 and T4 that is specially formulated at a compounding pharmacy.  

It’s important to get to the root cause of your thyroid issues first and to work with your doctor to determine what testing and treatment would be best for you.  

Understanding Your Thyroid

This guide gave you the foundations to understanding your thyroid. You learned:

• What the thyroid is
• How the thyroid works in your body
• How the thyroid is connected to other hormones in the body
• What causes alterations in thyroid function
• Two common thyroid disorders
• Supplements and medications to treat thyroid problems

Let me know in the comments: What’s something that surprised you about how your thyroid functions? What questions do you have about it? 

If you’re experiencing problems with your thyroid, you don’t have to go through them alone. Schedule an appointment with us to get down to the root cause of your symptoms. Let’s heal your thyroid!