Iodine Deficiency & The Functioning Thyroid

Iodine Deficiency & The Functioning Thyroid
Christine L. Foutch Naturopathic Physician Rock Island, Illinois

Christine Foutch is a practicing Holistic Physician in Rock Island, Illinois, specializing in Holistic Nutrition and Biomechanics. Holistic medicine is the art and the science of healing that addresses the whole person – body, mind, and spirit. The practice of holistic medicine integrates conventional and alternative therapies... more

The discovery of iodine was made by chance, during the earlier part of the 19th century.

It was in the year 1811, during the extraction of sodium salts for the manufacturing of gunpowder for the use by Napoleon’s army.

Bernard Courtois, a French chemist, observed an unusual purple vapor coming from seaweed ash that was treated with sulphuric acid that crystallized upon the exposure to a cold surface. With that, he sent off these purple crystals for further studies.

This unrecognized substance continued to be studied by Joseph Louis Gay-Lussac, Andre Anpere, Sir Humphry Davy, and a few others.

In 1813, came the first paper about, as well as a presentation for the new element Iodine, came out for the viewing public.

The earth’s soils contain varying amounts of iodine which will, in turn, affect the iodine content within our crops.  

In some regions, the iodine-deficient soils can be very common, which increases the risk of any iodine deficiencies among those individuals who are consuming the foods grown in that area.

The adequate levels of iodine are generally found within the soils and the waters of the more coastal regions.

Historically, iodine deficiency was regularly found within the mountainous regions of the United States and Mexico, and the so-called “goiter belt” around the Great Lakes. Mountainous areas, such as the Himalayas, Alps, and Andes regions, along with the river valleys that are prone to flooding, especially in South and Southeast Asia, are among the most iodine-deficient regions in the entire world.

Iodine is a trace element, a micronutrient that is naturally occurring in some foods, added to others and is also available as a dietary supplement.

The relationship between iodine deficiency and thyroid disease has been known since the early twentieth century.

Approximately 3600 BC, within the early Chinese Medical literature, you can find the first records of the decrease in the size of the Goiter with the ingestion of Seaweed and the burnt sea-sponge.

Throughout history, iodine had not even been discovered yet; though these remedies of the ingestion of the Seaweed and the burnt Sea-Sponge remained, were effective and used globally. From which we see in the documented writings by Hippocrates, Galen, Roger, and Arnold of Villanova in the later centuries.

The thyroid hormone, which is often referred to as the body’s major metabolic hormone, is actually 2-Iodine containing amine hormones: Thyroxine (T4) and Triiodothyronine (T3). T4 is the major- hormone that is secreted by the thyroid follicle cells out into circulation.

Most of the T3 is formed by and at the targeted tissues by the conversion of  T4 forming T3.

Both the T4 and T3 are constructed from 2-linked Tyrosine amino-acids.

However, T4 is bound by 4-iodine-atoms and T3 is having the 3 bound iodine atoms.

The thyroid hormone affects basically every cell within the body.

Like a Steroid, you could say, the thyroid hormone enters into the targeted cell; binds to the intracellular receptors that are within the nucleus of the cell and initiates the transcription factors for cellular Protein synthesis.

What does this do?

  1. Increases the basal metabolic rate and the body heat production, by turning on the transcription of genes involved within glucose-oxidation. This is the hormones calorigenic-effect.
  2. Regulation of tissue growth and development. The thyroid hormone is critical for the normal skeletal and nervous system development, as well as the maturation of the reproductive capabilities.
  3. Maintaining blood-pressure, by the increase in the number of Adrenergic receptors in the blood vessels.

The thyroid gland is a bit unique, out of all the endocrine-glands; as it can store its hormone outside of the glandular- cells, extracellularly.

This storage of the hormone is done so within large quantities.

The appropriately functioning thyroid gland has the ability to store enough colloid for the normal production levels of the thyroid hormone for about 2-3 months.

When the thyroid stimulating hormone is released from the anterior pituitary gland, it stimulates the thyroid, by binding it to the receptors on the thyroid follicle cells.

The first response is to release the stored thyroid hormone. The second response is to begin the synthesis of the new colloid, for the purpose of restocking the shelves, you could say.

Iodine is an essential component of the thyroid hormones thyroxine (T4) and triiodothyronine (T3), which regulate many important biochemical reactions. This is including protein synthesis, and then, of course, enzymatic activity, which is the critical determinants of most of our metabolic activities.

Iodine is a trace element in soil and water, which is ingested in many chemical forms. Most forms of iodine are reduced to iodide in the gut. Iodine is completely absorbed in the stomach and the duodenum (the first 10- inches of the small intestine). It is cleared from circulation, primarily by the thyroid and kidneys.

Iodine is known to control thyroid function.

For the production of functional iodinated thyroid hormones, the follicular cells must accumulate the anions of iodide from the blood. Not to get too overly complicated, but the Iodide-anions must become trapped within the follicular cells, as the concentration of the iodide is 30-times higher within the cell than within the blood.

Once trapped within the follicular cells, iodide moves to the follicular lumen by facilitated diffusion. At the border of the follicular cell and colloid, the iodides are oxidized and converted to iodine; attached to the Tyrosine amino acid and linked together to form the T3 and T4.


Anatomy & Physiology Textbook 6Th edition

Pathophysiology 6Th edition