Several years ago, I wrote an article about the thyroid gland, which I still believe is one of the most misunderstood glands in the human body. Since then, research discoveries have taught us even more about how the thyroid functions and how it can be supported. So today I would like to bring you additional information on the multifunctional thyroid gland.
IMPORTANT NOTE: Many of you reading this article have been diagnosed with, and perhaps are being treated for, a condition involving your thyroid. This article contains general information only. A complete accounting of the intricacies of this complex endocrine (hormone secreting) gland would require a series of weekend seminars. DO NOT in any way alter any form of therapy–pharmaceutical or otherwise–that has been prescribed for you by your treating doctor.
My intent today is to familiarize you with the basic anatomy and physiology of the thyroid gland, which includes its functions as well as the intricate ballet it performs in regulating many varied functions of our body.
BASIC THYROID ANATOMY
The thyroid is a butterfly-shaped gland that lies at the front, lower portion of the neck. It lies over the trachea or “windpipe” and is composed of a left and right lobe--each of which are positioned on either side of the neck--connected by the isthmus. It can be felt just below the larynx or “Adams apple.”
Two protective layers surround the thyroid gland. An outer layer which connects to the muscles of the larynx and the nerves that surround the gland. The second layer lies between the gland and the outer layer. This allows the gland to move freely when you swallow or talk.
BASIC THYROID FUNCTION
Both lobes contain specialized cells or follicles which produce and contain the hormones that are released by the thyroid gland. There are two types of these cells: the follicular and parafollicular cells. Each of these two cell types produce different forms of hormones, which are released into the blood stream and then are used to regulate many different functions of the body.
The primary function of the thyroid gland is to control all metabolic functions of the body. These include your temperature, heart rate, hair loss from the scalp and eyebrows, bone growth, brain function, digestion, energy, the rate of your metabolism, and menstruation (to name a few).
The follicular cells make up the majority of the thyroid gland tissue. They produce two different hormones. The first, which makes up the majority of the hormone that the gland produces, is commonly referred to as T4 (thyroxine). The thyroid also produces a much smaller amount of T3 (triiodothyronine). There are also a couple of other hormones which are produced in much smaller quantities as well.
The parafollicular cells (also known as C cells) produce another hormone called calcitonin which regulates calcium and phosphate levels in the blood.
In clinical practice, I have seen patients who experience changes in the texture and coloration of the skin as well as the tone of their voice due to variations in thyroid function.
COMMON IMPACTS TO FUNCTION
In some instances, the thyroid gland can become enlarged. This condition is called a thyroid goiter. Thyroid nodules can also develop and these in some instances can evolve into thyroid cancer. Typically, if you have either one of these two conditions, they will be discovered through a diagnostic ultrasound. In some instances, your doctor may suggest a biopsy of a nodule or goiter.
There are a number of things that can impact the function of the thyroid gland. These include both genetics and epigenetics (chemical reactions to environment and lifestyle). As I have said many times in past articles, just because you have a genetic predisposition to a particular condition or situation, it doesn’t necessarily mean that you will demonstrate that condition or symptom. Your lifestyle can and is a significant factor in whether or not you will manifest that for which you have a genetic predisposition. Your lifestyle will allow you to either turn on or turn off that gene in many instances.
An underactive thyroid is called hypothyroidism, the most common of which is called Hashimoto’s thyroiditis. The opposite form of thyroid dysfunction is called hyperthyroidism, also known as Grave’s disease. Both Hashimoto’s thyroiditis and Grave’s disease have also been shown to be dependent, to a significant degree, on both the genetics and epigenetics of the individual.
Many different types of infections can affect thyroid gland function. These include chronic hepatitis C, H. pylori, HIV, herpes virus (about which I will be writing in an upcoming article), SARS-CoV-2 as well some mounting evidence that B. burgdorferi (which is the bacterium that causes Lyme disease).
As in many other body systems, stress can significantly impact thyroid function. The inflammatory process that stress induces contributes in some instances to the development of inflammation which studies demonstrate can contribute to Hashimoto’s thyroiditis in those who may already be genetically predisposed to the condition.
Nutritional deficiencies of such substances as a lack of vitamin D, iodine, selenium, and iron can contribute to the development of thyroid pathology particularly in those genetically predisposed. Equally an exposure or overload of certain toxins can alter thyroid function. These toxins include mercury, nitrites, certain pesticides, PCBs, and flame retardants.
Radiation exposure has also been demonstrated to increase the risk of developing autoimmune thyroid conditions.
However, we will not be discussing these in this article. I encourage you to further study the details of these or any condition you might have been diagnosed with on your own.
NEXT MONTH
I would venture to guess that the vast majority of you who have been diagnosed with a thyroid condition suffer with an “underactive thyroid.” The term “Hashimoto’s disease” or “Hashimoto’s Thyroiditis” may or may not have been used to describe your symptoms. There are a number of different names for an autoimmune thyroid that may be used. For the purposes of this article we will be referring to “Hashimoto's Thyroiditis.” This is probably the most common term used to describe an autoimmune disease of the thyroid gland.
However, it is worth asking whether or not any thyroid antibody testing was performed. As you will see when we discuss how thyroid dysfunction is diagnosed, you will recognize that there are a number of different specific tests that may be run on your thyroid gland. Oftentimes your conventional healthcare provider may not run them all. There are reasons for this, which I will reveal to you in the next installment of this article.
I hope that I haven’t overwhelmed any of you with the information so far. I would like to stop here for now and let you give some thought to what you just read.
Until then, if you have any questions about what I have presented here, please feel free to email them to us at [email protected].