The thyroid is a small butterfly shaped gland located in your neck. Though it weighs only about an ounce, the thyroid gland has some very important functions to carry out that have a major impact on one’s health.
The thyroid maintains body temperature, controls the rate of energy production (including oxygen use and basal metabolic rate), regulates the skeletal and muscular growth of children, and heavily influences brain chemistry. Additionally the thyroid gland has major influence in many other areas.
- Enhances a portion of the nervous system called the sympathetic nervous system.
- Promotes breakdown of blood sugar, mobilizes fats essential for protein synthesis.
- Enhances the liver’s synthesis of cholesterol.
- Promotes normal adult nervous system function and mood.
- Promotes normal functioning of the heart.
- Promotes normal muscular growth and function.
- Promotes normal GI motility and tone.
- Increases secretion of digestive juices, particularly that of the gallbladder and the stomach.
- Promotes normal female reproductive ability and lactation.
- Promotes normal hydration and secretory activity of the skin.
The thyroid gland takes iodine, a chemical element found in many foods, and converts it into thyroid hormones thyroxin (T4) and triiodothyronine (T3). It is estimated that iodine makes up about 0.00004% of total human body weight and is found in highest concentration in the thyroid gland cells.
These cells combine iodine and the amino acid tyrosine, residue from the protein thyroglobulin, to make the hormones T4 (thyroxin) and T3 (triiodotyrosine). These hormones are then released into the blood stream and transported throughout the body, attached to a protein called Thyroid Binding Globulin (TGB).
It is important to understand that T4 is an inactive thyroid hormone and that 93% of the thyroid’s production of hormone is T4. Only about 3% of the hormone that the thyroid gland produces is active thyroid hormone (T3). The 93% inactive T4 hormone must be converted to T3 in order for this active hormone to generate all the important effects in the body. 60% of T4 is converted to T3 in the liver and 20% is converted into another inactive thyroid hormone called reverse T3 (rT3).
Another 20% of T4 is converted to T3 Sulfate (T3S) and triiodothyroacetic acid (T3AC) and is acted upon by the digestive tract bacteria (assuming that your digestive tract is in healthy balance of bacteria) and fully converted to T3. Any remaining T4 hormone that wasn’t transformed into T3 or inactive T3 forms will be converted into T3 by the peripheral tissues (found in brain cells and muscles cells).
Only the active T3 hormone exerts is controlling effect on metabolism and all the other functions it governs or modulates. It sounds a bit complicating but it is very important.
The thyroid is the MASTER GLAND of your metabolism and so it has a crucial job. People who suffer from thyroid malfunction experience many different kinds of health complications, affecting many different systems in their body.
Every cell in your body has thyroid hormone receptor sites, so this little gland affects the function of every cell in your body!
An estimated 27 million Americans suffer from thyroid dysfunction, half of which go undiagnosed. Women are at an estimated 24 times greater risk of developing thyroid malfunction. This risk increases with age and for women who have thyroid dysfunction within their family.
When the thyroid gland begins to malfunction, many doctors neglect to ask the very important question of why.
Signals of a depressed thyroid include:
- Adrenal problems, hormonal imbalances.
- Poor blood sugar metabolism.
- Irregular immune function.
- Gut infections.
- and more.
Many times replacement hormones are used in an effort to wipe out symptoms without understanding what has caused the thyroid to malfunction in the fist place. More often than not the relief these drugs provide is short lived, or never actually works.
In order to really address the health of the very important thyroid gland, the systems of the entire body must be taken into account.
So, even though you are taking medications for thyroid dysfunction, you may still have problems with your thyroid (even though your TSH levels are in normal range). For example, you can have problems with how the thyroid hormones are transported.
Or you can have a problem with how inactive T4 hormone is converted to active T3 hormone. You may have issues with the end effect the thyroid is intended to have at the cell level.
To understand the testing involved in identifying your thyroid disfunction read our in-depth analysis of the testing process.