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Picture 2. Enlarged thyroid gland losses it shape Overactive thyroid, thyroid hormones, thyroid home tests easy to use home health tests, test kits

What are Thyroid hormones and why do we need them?

What this article about the thyroid will tell you

Thyroid gland and its hormones are a topic often discussed by popular health and lifestyle shows and magazines. Proper functioning thyroid gland is essential to maintaining a healthy and active lifestyle. The text before you is meant to reveal facts about thyroid gland and what hormones it produces, as well as stress out what are the most common diseases that affect this gland and how does it reflect on your health.

Further, it will showcase symptoms of thyroid dysfunction and inflammation. Lastly, it will signify what ways are there to measure thyroid hormones, especially home testing, and which actions you can take to fix them back to optimal levels.

“What is the thyroid gland and what does it do”

Normal thyroid gland is located in central region of the neck below Adam’s apple easily palpable trough skin. It consists of two smooth, firm lateral lobes with a central bridge connection the two called isthmus. Thyroid is a gland which means it creates certain chemical compounds which regulate different systems in our body.


 These compounds are called hormones, and thyroid secretes them directly in bloodstream which makes thyroid an endocrine gland. What are the hormones produced by thyroid then you must ask. There are two hormones which are synthesized in thyroid – thyroxine (T4) and triiodothyronine (T3). Their primary role is to regulate body’s metabolic rate (1).

Picture 1. Thyroid gland anatomy and location Home testing kits, what are thyroid hormones, thyroid function. Courtesy of: National Cancer Institute- visuals online, illustrator: Don Bliss

What hormones are released from the thyroid gland

As mentioned above, T3 and T4 are produced and secreted by the thyroid. These hormones have similar chemical structure but T3 is more potent and has a shorter life-span.  However, the thyroid gland produces T4 twenty times more than T3 (2). Production of these hormones is regulated by another hormone in the body which is produced by an endocrine gland called pituitary gland. This gland is located in the skull on a stalk extending from brain and it produces a hormone called thyroid stimulating hormone or TSH.

What is TSH and what does TSH do are crucial questions one must ask to understand how thyroid works. THS stimulates thyroid gland to produce T3 and T4 and secrete it in blood.  In turn concentration of T3 and T4 in the blood regulates production of TSH in the pituitary gland. Simply put, if there is too much T3 and T4 – the TSH secretion and blood concentration is lowered. The opposite happens when T3 and T4 are lowered – the TSH level in the blood is increased (3).

What do the hormones from the thyroid gland do to you and the body

Both T3 and T4 travel through blood almost exclusively bound with proteins in blood stream. This enables their even distribution through entire body. There is not one protein but predominately T3 and T4 are bound to a protein called thyroxine-binding globulin (TBG). Small fraction of about 0,02% of T4 and 0,3% of T3 are not bound and are called free T3 and T4 (2). This free fraction is the one that is active and inhibits pituitary secretion of TSH. 

Another indicator measured is reverse T3 (rT3). This is an inactive faction of this hormone. Certain conditions can cause T4 to reverse into inactive T3 instead of active T3. These tend to follow T4 levels: the levels are lower when T4 is lower and higher when T4 is higher (16).  

What do thyroid hormones do the body?

T3 and T4 cause many effects on different parts of body. Primarily, they increase metabolic rate which in turn increases calorie consumption and as bi-product heat production is also increased. Along with that, they affect tissue growth and maturation, as well as regulate fat metabolism and increase sugar absorption from intestine (1).

What are is the correct thyroid hormone levels to have

As with other biochemical blood parameters thyroid hormones vary in range which is considered optimal for overall body health and thyroid health. These levels are represented in table down below.

Table 1. Normal T3, T4, TSH blood level ranges (2, 4).
Hormone T3 T4 TSH
Blood (serum) level- (Total T3 and T4) * 0,08-0,22μg/dL(US) 1,2-3,3nmol/L(EU) 5-12μg/dL (US) 65-156nmol/L(EU) 0,4-4,0mU/L
Free fraction 230-619 pg/dL 0.7-1.9 ng/dl
Reverse T3* 10-24ng/dL(US) 0.1536-0.36864 nmol/L(EU)
Serum half-life 2d 6-7d

These levels can vary if thyroid or pituitary are not functioning properly or are affected by tumours or inflammation.  TSH levels are sensitive to changes of T3 and T4 levels in blood so if TSH is normal one can with much certainty exclude thyroid function problems. However sometimes TSH can be misleading, as in pregnancy where there is slight drop in TSH or in response to medications (corticosteroids or dopamine).

Higher levels of TSH can also be found in pituitary tumours which can also be misleading if a person is testing to determine the state of thyroid. That is why it is important even in home thyroid testing to determine T3 and T4 levels total and free alike, as well as TBG so that these common mistakes can be avoided (2).

What happens to you if you have unnatural thyroid hormone levels

Hormones are the body’s messengers (5). Previously mentioned T3 and T4 are crucial for regulating body metabolism and development of central nervous system in infants and children. (4)

So it is easy to see how important is to early detect and combat diseases of thyroid. Symptoms associated with thyroid dysfunction can be divided in two categories. One is when levels of thyroid hormones are beneath normal range and the other one when these hormones are above normal.

The first one is called hypothyroidism or underproduction of thyroid hormones and the second one is called hyperthyroidism or overproduction. Down below are listed symptoms most commonly connected with these conditions.

Table 2. Common signs and symptoms of thyroid disease (1, 2, 6, 7).
Hypothyroidism Hyperthyroidism
Symptoms and signs Fatigue Fatigue and muscle weakness
Weakness Hand tremors
Coarse, dry hair Mood swings
Hair loss Anxiety and nervousness
Dry, pale skin Skin dryness
Weight gain or increased difficulty losing weight Heart palpitations and irregular heartbeat
Menstrual cycle abnormalities (heavy bleeding) Weight loss despite increased appetite
Decreased libido Trouble sleeping
Memory loss and forgetfulness Diarrhoea
Cold intolerance Light or skipping periods
Decreased sweating Excessive sweating
Decreased exercise capability Warm, flushed skin
Deepening of voice Heat intolerance
Muscle cramps and frequent muscle aches Poor concentration
Ankle swelling Rapid speech
Slow speech and thinking Wide gaze

If these symptoms and signs are neglected, can lead to serious health complications even with lethal outcome. Here are some of the complications listed below.

Hyperthyroidism complications:

  • Eye problems leading even to loss of sight (25-50% have various eye symptoms and signs)
  • Birth and pregnancy problems:
    • premature birth
    • High blood pressure and fluid retention during pregnancy in mother and growth problems in baby- pre-eclampsia,
    • miscarriage
  • Osteoporosis (brittle and weak bones)
  • Irregular and abnormally fast heart rhythm called atrial fibrillation
  • Heart failure (10)

 Hypothyroidism complications:

  • Various heart problems:
    • High cholesterol
    • Heart failure
  • Pregnancy and birth problems:
    • High blood pressure and fluid retention during pregnancy in mother and growth problems in baby- pre-eclampsia
    • Anaemia in mother
    • Birth defects
    • Bleeding after birth
    • Problems with baby’s mental and motor development
    • Premature birth or low birthweight
    • Underactive thyroid in baby
  • Myxoedema coma– life threatening complication with drowsiness, confusion and hypothermia as symptoms leading to loss of consciousness (11).

To get an early grip on how your thyroid is, it is resourceful to use home thyroid test kits as they can help you detect changes of levels in time before symptoms and signs get out of hand and seriously endanger your health and impair your everyday life.

What types of thyroid diseases are there?

If your thyroid is not functioning properly, it usually reflects as too much or too little T3 and T4 in the blood.  Sometimes this can be due to other factors such as ingesting thyroid hormones, radiation exposure, medications such as amiodarone or just a simple thyroid inflammation.

This state in which the blood levels of T3 and T4 is above normal is called thyrotoxicosis. Although similar, these are not same as hyperthyroidism which is a result of excessive thyroid function of which thyrotoxicosis is normally a part of.


This disease affects as much 0,5% and 2% of women population. It is as much as 10 times more common in women than in men. Onset is commonly between age of 20 to 50 (8). Increase of gland’s function may originate from numerous reasons. Some of the most common ones are:

  • Grave’s disease
  • Toxic adenoma
  • Activating a mutation of the TSH receptor
  • Goiter (thyroid gland enlargement)
  • Drugs that make iodine excess
  • TSH-secreting pituitary cancer
  • Thyroid producing carcinoma metastases (2)

Most common one is Grave’s disease accounting for 60-80% of the cases. It is caused by a number of factors, genetic and autoimmune alike. Hyperthyroidism is manageable and people diagnosed can live a normal and fulfilling life. Uncontrolled hyperthyroidism can be the cause of sudden cardiac arrest, arrythmias, high blood pressure among other problems. This is why thyroid home health tests are important.

Picture 2. Enlarged thyroid gland losses it shape
Overactive thyroid, thyroid hormones, thyroid home tests easy to use home health tests, test kits


This state is caused by different mechanism or causes and it affects women more than man. It occurs in around 1-2% of women and much more in population over 50 years of age. It is up to 10 more common in women than in men, affecting as much 12 per 1000 women (8). Most common causes of hypothyroidism are:

  • Autoimmune hypothyroidism: Hashimoto’s thyroiditis, atrophic thyroiditis
  • Treatment of other thyroid conditions which result in partial or whole thyroid destruction:
    • Thyroid radiation treatment
    • Thyroid partial or total removal
    • Cancer destruction
  • Iodine deficiency
  • Systemic disorders:
    • Scleroderma
    • Amyloidosis
  • Disease of pituitary gland and hypothalamus
  • Congenital (since birth)
  • Goiter (2)

Most common cause of hypothyroidism is Hashimoto’s thyroiditis an autoimmune state. Researchers from Ohio’s Cleveland Clinic claim that hypothyroidism, even subclinical variety increases chances of death from coronary heart disease and death overall. (9) Also, complications of untreated hypothyroidism can be very severe even leading to death. It is safe to say then, that early disease detection and tracking through home test kits along with therapy can help prolong and increase quality of life living with hypothyroidism.

Picture 3. Goiter, often seen as an enlargement of the neck, Home thyroid testing, thyroid nodule, thyroid hormones easy to use home health tests, test kits Courtesy of CDC,

“Can thyroid abnormalities turn into cancer”

Thyroid gland size and shape change can often be felt or even seen by doctor or patients. However, not all enlargement is cancerous. Some of these can be even, meaning the gland as whole is enlarged which is called goiter, and sometimes it can be just an enlarged lump- nodule.

There are many reasons why gland can become enlarged and it is much more often due to benign states than cancer. Around 2 to 3 thyroid nodules out of 20 are revealed to be cancerous in nature (12).

Thyroid nodules are more often develop in older adults but can be seen in all age groups. Nodules can either be hormone producing or not. Hormone producing ones are almost always benign in nature (12).

If anything, when there are visible signs of thyroid enlargement or you have felt a strange lump in your neck, it is wise to see a doctor for further information and diagnostic planning.

Genetics and thyroid disease – can it be inherited?

Topic of thyroid disease and inheritance remains an open discussion scientific world. It is known that Graves disease (hyperthyroidism) can cluster in families and having a close relative can increase the risk of developing disease by yourself. However, many environmental and genetic factors are included so no single pattern can be established (13).

As for hypothyroidism, most cases of congenital hypothyroidism are sporadic, meaning it occurs without inheritance pattern (14). Hashimoto’s thyroiditis like Graves has no established inheritance pattern but it is general opinion that if a close relative has it risk of getting the disease is higher (15).

“How to test your thyroid hormone levels”

Thyroid health can be inspected through many diagnostic means. Apart from simple gland inspection and palpation, analysing blood for thyroid related indicators is one of the cheapest and efficient ways to get the picture of what is happening. Home testing kits are a cheap, fast, more practical way of getting essential information about thyroid function.

Generally when testing for thyroid hormone levels blood sample is needed. This can be either obtained by finger prick or elbow vein blood sample. Home thyroid test kits test for a variety of biochemical indicators, all of which are devised to asses and separate different thyroid function problems and show what further diagnostic and/or treatment is needed. These tests often use finger prick method which is much easier, less scary and simpler. However, it is important to stress out that if any or all of these are out of range doctors’ opinion on further action is needed.

Thyroid hormone home test kit

T3 and T4 are the hormones usually measured with TSH to establish a baseline for thyroid function. Both T3 and T4 can be measured in their free faction or in total. Thyroid hormones bind to thyroxin-binding globulin (TBG) in bloodstream which in turn carries them throughout the body. All of these compounds can be measured by home test kits giving you a wider picture about thyroid function. Another thing which is commonly measured is an antibody called TPO antibody. TPO stands for Thyroidal peroxidase and is an important enzyme which forms thyroid hormones from chemical compounds. Our immune system sometimes mistakenly recognizes it for a threat and produces antibodies which in turn render TPO useless. This is a base for a condition called autoimmune hypothyroidism. Another antibody present in that state is thyroglobulin antibody (TGO) named after another chemical compound found in thyroid. Another indicator measured is reverse T3 (rT3). This is an inactive faction of this hormone explained above.

Thyroid hormone test

Thyroselect Panel

True Health Labs

It can test all of the parameters of thyroid function free T3,T4, total T3,T4, TSH, reverse T3, TPO Ab, Tg Ab, TBG, T3 uptake


  • Check list so you can customize testing


  • Price.
  • You must go to specific location to leave the test

Thyroid hormone test

Thyroid test


Measures TSH, TPO, free T3, and free T4


  • Simple
  • Plenty of instructions and video materials
  • Results can be visible from account during weekends


  • Internet registration
  • Availability not worldwide

Thyroid hormone test

Thyroid profile


TSH, free T3,T4


  • Internet   results
  • Cheap


  • Doesn’t have TPO Ab

Thyroid hormone test

The blood code thyroid discovery panel

Free T4, Free T3, TPO antibody


  • Good baseline for further testing


  • Expensive
  • Site doesn’t contain much information
  • Must come to lab to give results

Thyroid hormone test

Comprehensive Thyroid Panel


TSH, total T4, free T4, free T3, Tg Ab, TPO ab, reverse T3


  • Lots of parameters tested
  • Price


  • Must go to testing lab for sampling

Thyroid hormone test

Thyroid Enchanced Function test kit

Health test express

TSH, free T3, T4, TPO Ab


  • PriceFree shipping


Things that can improve my thyroid function

There are certainly a few ways to improve your thyroid function without medications prescribed by doctors. The most important nutrient to look for in food for the thyroid is iodine. Iodine levels in the body control thyroid function and when low it can cause hypothyroidism. Iodine usually is mixed in with table salt but in some part of the world that is not the practice and eating kelp and seaweed might help as a substitution.

Food you should avoid or moderately eat is soy, broccoli, cabbage and coffee. People who are already on a hypothyroidism hormone replacement therapy should avoid processed sugar, fatty foods, and gluten as they are known to cause problem with medication intestinal absorption.

You should consider adding or increasing intake of nuts, whole grains, fresh fruits and vegetables and fatty fish as they are considered to improve general health and help improve thyroid function (17).

Lifestyle changes or improvements such as exercise have shown to control the weight in patients with hypothyroidism and also increase production of thyroid hormones. You should also consider quitting smoking as it is a risk connected with almost every disease known to man. Last but not least, maintaining regular sleep is also important as it reduces stress and helps improve general health an important thing to achieve hormonal balance.

Conclusion and why it is important to track your thyroid hormone

Testing thyroid hormone levels is imperative to keep track or discover early onset of disease. Home thyroid testing is a cost and time effective way of making sure that thyroid functions optimally. When diagnosed early, thyroid disease is a manageable and person can leave a long and fulfilling life. This is why thyroid home levels testing is an important tool for keeping your health in check.

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  1. Gary D. Hammer, Stephen J. McPhee, 2014., Thyroid, Pathophysiology of Disease, 7th Edition
  2. Larry Jameson, Anthony S. Fauci, Stephen L. Hauser, Eugene Braunwald et al., 2017. , Harrison’s Endocrinology 4th Edition, McGraw-Hill Press: New York.
  3. Arthur C. Guyton, John E. Hall.—11th ed. -2006.- Elsevier Sounders -Textbook of medical physiology
  4. Unknown author, 13.10.2010., Thyroid function tests, Endocrineweb,
  5. Unknown author, unknown date, Hormones, Medline plus
  6. James Norman MD, 17.02.2018, Hypothyroidism: Overview, Causes, and Symptoms, Endo
  7. Grazia Aleppo MD, 07.04.2017, Hyperthyroidism Overview: Overactive thyroid makes too much thyroid hormone, Endocrineweb
  8. Mark P. J. Vanderpump, 2011,  The epidemiology of thyroid disease, British Medical Bulletin (BMB)
  9. Unknown author, Hypothyroidism is linked to increased risk of coronary heart disease, death, 03.08.2011, Endocrineweb,
  10. Unknown author, unknown date, Overactive thyroid (hyperthyroidism), NHS UK
  11. Unknown author, unknown date, Underactive thyroid (hypothyroidism), NHS UK
  12. Unknown author, 31.03.2016., What is thyroid cancer? American Cancer Society
  13. Unknown author, 12.06.2018, Graves disease, Genetic home reference
  14. Unknown author, September 2015, Congenital hypothyroidism, Genetic home reference
  15. Unknown author, February 2015, Hashimoto’s thyroiditis, Genetic home reference,
  16. Unknown author, unknown date, T3 (Triiodothyronine), Reverse, Serum, Mayo medical laboratories
  17. Unknown Author, unknown date, Complete guide to boosting thyroid hormone function naturally ,