Thyroid hormones, we tell you everything!

Historical references to what we know today as the thyroid gland have their roots in ancient times and early medical history. We must go back to 1600 BC, when the Chinese used a burnt sponge and seaweed to treat an enlarged thyroid. Traces have also been found in Indian Ayurvedic medicine.

The use of this treatment then evolved over time. There was a goiter epidemic in the Alps where it was first described as a neck tumor in the 14th century.

It was in 1656 that Thomas Wharton The thyroid gland was named for its shield shape. In 1811, iodine was discovered in burnt seaweed in Paris, and it was immediately speculated that this was the active ingredient that made the treatment of hyperthyroidism effective.

After 10 years, Proust recommended iodine as a treatment and Robert Graves, for his part, subsequently published a work on goiter in 1835.
It was in the 19th century that thyroxine (T4) was isolated by Edward Calvin Kendall. C.R. Harington then synthesized the hormone, followed by the T3 which was also isolated and synthesized in turn.

These two hormones have since been continuously improved and made available for medical use for the benefit of all. Today, natural thyroid hormones containing a mixture of T4 and T3 provide effective treatments for various thyroid hormone disorders.

Thyroid hormone is secreted by the butterfly-shaped gland at the base of your neck, the thyroid, which sits in front of the windpipe and just below the vocal cords or larynx. Although small, the thyroid plays a major role in controlling many of our bodily processes through the thyroid hormones T3 and T4 it releases, primarily for regulating metabolism. You may feel tired most of the time or restless, and experience weight loss or gain, even with a proper diet.

Your heart rate and body temperature can be raised and lowered. It controls the speed at which food moves through your digestive tract, the breakdown of food and its conversion into energy, the rate at which your body burns calories, and how quickly cells regenerate and are replenished.

Thyroid diseases such as goiters, hyperthyroidism, and hypothyroidism depend on how much or too little of this hormone is produced.

Thyroid hormone production

The production of thyroid hormones affects all organs and cells in the body. There are two types of hormones released by the thyroid gland: thyroxine (T4) and triiodothyronine (T3). The thyroid gland uses two raw materials in the production of thyroid hormones:

Iodine.

Thyroid cells have a unique function specialized to absorb and use the’iodine in its processes. Iodine comes from the food you eat, taken up into the bloodstream by thyroid epithelial cells that contain a sodium-iodide symporter on their outer plasma membrane. Once the iodide is trapped, it is then transported into the lumen of the follicle along with thyroglobulin.

Tyrosines.

These molecules originate from thyroglobulin, a large glycoprotein synthesized by the epithelial cells of the thyroid gland and subsequently secreted into the lumen of the follicle. Tyrosine residues form two groups: monoiodotyrosine (MIT) and diiodotyrosine (DIT). Two diiodotyrosines, when linked, form thyroxine, and a combination of MIT and DIT particles produces triiodothyronine.

An adequate supply of iodine is essential for achieving normal thyroid hormone production levels. Iodine deficiency prevents the thyroid gland from producing thyroid hormones and can negatively impact your body's growth, metabolism, heart rate, other critical functions, and overall well-being. Iodide is the first element involved in thyroid hormone synthesis, which is then converted to iodine and eventually condensed into tyrosine residues.

The thyroid peroxidase enzyme acts as a catalyst for the iodination of tyrosines on thyroglobulin, and the synthesis of bioactive agents activates T3 and T4. The reaction with the thyroperoxidase enzyme allows thyroid hormones to accumulate in the follicle colloid and then on the surface of thyroid epithelial cells. These cells ingest the colloid via endocytosis, and the vesicles fuse with lysosomes, releasing thyroid hormones.

The thyroid gland works in conjunction with the pituitary gland, which releases TSH, or thyroid-stimulating hormone. TSH secretion prompts the thyroid gland to release more of this hormone; a high TSH level indicates an underactive thyroid, while a low TSH level indicates an overactive thyroid. A normally functioning thyroid produces approximately 801 TP3T of T4 and approximately 201 TP3T of T3.

 

T3: Triiodothyronine

Triiodothyronine, or T3, is one of the two hormones produced by the thyroid gland, the other being T4. T3 is identical to T4, except that it has fewer iodine atoms in each molecule. T3 is the more active hormone produced from T4, which is deiodinated by three deiodinase enzymes.

Triiodothyronine is composed of:

1. Type I which is present in the kidneys, liver, thyroid and pituitary gland.
2. Type II found in the CNS, pituitary gland, heart vessels and brown adipose tissue.
3. Type III present in the placenta, the central nervous system, and a hemangioma.

The effects of T3 on target tissues are more potent than the effects of T4. Most of the T3 in your blood binds to the protein, and the unbound T3 is called free T3. Measuring the T3 in your blood can help doctors determine if you have a thyroid problem.

Potential disorders would include hyperthyroidism when the thyroid produces excessive hormones, hypothyroidism when the thyroid glands do not produce normal amounts of thyroid hormones, thyrotoxic periodic paralysis which results in muscle weakness, or toxic nodular goiter when the thyroid gland malfunctions and has rounded growths.

T4: Thyroxine

Thyroxine, or T4, is the prohormone produced by the thyroid gland along with T3. T4 in the blood also binds to proteins, just like T3, and those that do not bind and remain unbound are called free T4. It is composed of four iodine molecules attached to its overall molecular structure, which affects almost all processes in the human body.

It may be less potent than T3, but it is produced in significantly higher quantities and has a longer half-life. It is considered the prohormone because it serves as a reservoir for T3, while T4 is converted into the tissues your body requires.

Measuring T4 can help diagnose thyroid problems, where symptoms include bags under the eyes, dryness, irritation, swelling, dry skin, hair loss, increased heart rate, weight changes, anxiety, sleep disturbances, fatigue, constipation, and irregular menstruation.

The highs and lows indicated by a T4 test would indicate disorders similar to what doctors may find when performing a T3 test.

Medical uses for thyroid hormones

Thyroid hormones are very useful in medical applications. T3 and T4 hormones are commonly used to treat hypothyroidism, a condition caused by an underproduction of hormones by the thyroid gland. Hypothyroidism is typically caused by... Hashimoto's disease, an inadvertent weakening of the thyroid gland by radiation therapy treatments or surgery or by drugs that reduce thyroid hormone levels.

Thyroid hormone therapy aims to restore normal thyroid function. Pure T4 and synthetic thyroxine are the best options for mimicking a natural thyroid hormone and work remarkably well to replace the missing hormone.

Thyroid hormones can be taken orally and are well absorbed by the intestines. They should not be taken more than once a day because the hormones remain in our bodies for a long time, and they also appear at very stable levels once they circulate in the blood.

The ultimate goal of thyroid treatment is to maintain thyroid function at the same rate as in people without thyroid problems. The best time to take TSH is first thing in the morning, on an empty stomach, as TSH can be more difficult to absorb in the presence of food. The key to a well-functioning thyroid is to be consistent in taking your thyroid hormone medication at the same time every day, but be sure to check with your doctor or pharmacist if you are taking other medications.

Studies show that patients with hypothyroidism who take thyroid hormones for medical purposes experience positive changes, which include the following:

• A noticeably improved energy level throughout the day.
• Regulation of mood, general well-being and stimulation of mental functions such as memory retention and critical thinking.
• A lower level of triglycerides and cholesterol.
• Normalization of growth in children that had been delayed due to the condition. An immediate growth spurt, as if the thyroid were functioning again, when they take adequate doses.

 

Sports uses of thyroid hormones

Thyroid hormones are no stranger to the world of sports. Sports and their rigorous, demanding daily training can exhaust the body and directly affect the thyroid gland. Thyroid hormones are present in various forms within this discipline.

Prescription medications such as pills and tablets are taken in powder form. It should also be noted that the level of thyroid hormones determines the speed or slowing of the basal metabolic rate; this is vital information for all runners and bodybuilders.

Putting the body in a situation similar to hyperthyroidism will allow the user to burn more calories in the form of heat, a rise in body temperature called thermogenesis.

There is still ongoing scientific debate about how thyroid hormones are used as a performance-enhancing supplement, as there is also a correlation suggesting that intense training can overtax the thyroid gland over time. This can easily backfire, given the importance and value the thyroid gland plays in our daily lives.

It is a proven fact that running in endurance mode can reduce the production of thyroid hormone and eventually the runner or bodybuilder will need to consult a doctor or specialist coach.

 

Thyroid hormones for weight loss

It has been previously concluded that the thyroid plays a vital role in regulating body weight, metabolism, and helping our body stay warm, use energy efficiently, and keep our brain, heart, muscles, and other organs functioning as they should.

The thyroid hormone regulates metabolism in humans and animals. Metabolism can be measured by the amount of oxygen our body uses in a specific period of time. BMR or basal metabolic rate, is the figure obtained when the measurement is taken at rest. BMR was one of the main test indicators used to determine whether a patient had an underperforming or overperforming thyroid.

T3 also plays an important role in increasing a person's BMR. When thyroid hormones are introduced into the system, they increase the metabolic rate and can:

• Increase the number of calories needed for normal bodily processes, even when the body and muscles are passive and at rest.
• Increase the distribution and utilization of most of the nutrient macromolecules created in the body.
• Increase the amount of energy and oxygen our body uses.
• Increase the primary energy-generating complex in the body, which is the population of ATPase, sodium, and potassium.

Given the benefits, thyroid hormones can be taken as a weight loss supplement, particularly in cases where it stimulates fatty acid metabolism and breaks down fat stored in adipose tissue.

Simply put, the T3 Thyroid hormones increase the overall basal metabolic rate, which digests all food groups more efficiently, unlocks massive energy for the body to use, and can have a profound and immediate effect in overweight people with diagnosed or undiagnosed hypothyroidism.

Creating an exercise regimen supplemented with regular thyroid hormone supplements yields more effective results because the hormone provides the body with abundant energy, encouraging vigorous movement. Unlike artificial stimulants such as synephrine or caffeine, thyroid hormone supplements increase metabolic rate without the jitters and do not cause a "crash" when the effects wear off.

It should be noted that the supplement should be taken in moderation and the user should bear in mind not to take too much and enter a state of hyperthyroidism.