My first time hearing the word thyroid was years ago when just a girl. Mom had developed a goiter; consequently, surgery was performed to remove it. As I grew up and older, doctors wanted to run tests to see if my thyroid was normal. This led me to do a little research to find out for myself more about this organ.
The thyroid itself is a rather small, bow tie shaped gland located in the front of the neck below the larynx (Adam’s apple). It is part of the body’s endocrine system. The endocrine system consists of organs and tissues that produce, store, and secretes hormones directly into the bloodstream.
The hormones in the thyroid contain a high concentration of iodine – 80% of iodine in the body, in fact. If there is a deficiency of this element, the result can be an enlarge thyroid, or goiter. Particularly in children, this deficiency of iodine can block hormone production resulting in stunted physical, mental, and sexual development. This condition is called cretinism.
But, just how does the thyroid work? There are 3 types of hormones inside this gland – T3 (triiodothyronine), RT3 (reverse triiodothyronine) and T4 (thyroxine). When the body needs more thyroid hormones this gland secretes T4 into the bloodstream, then T4 (and its derivatives, T3 and RT3) affect all other cells in the body.
These hormones regulate the rate of the body’s metabolism which promote normal tissue growth and repair, affect cardiac rate, and maintain the production of energy for muscle and body heat. Also, the thyroid hormones assist the liver to remove excess bad cholesterol (triglycerides and low-density lipoproteins) from the bloodstream. The bad cholesterol is moved to the bile, then to the feces. So, too little thyroid hormones can cause an increase in bad cholesterol and a decrease in good cholesterol (high-density lipoproteins). Thyroid hormones can even affect the bowel movements – too much of this hormone resulting in too frequent bowel movement, and too little, constipation.
Finally, what controls the thyroid anyway? It all starts in the brain. This area is called hypothalamus.