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Facts about Thyroid Disorders - Hyperthyroidism & Hypothyroidism

A Botany graduate, Nithya Venkat enjoys researching and writing about topics that interest her.

Thyroid Gland

Thyroid Gland

The thyroid gland produces hormones that are responsible for the proper functioning of the body system.

Thyroid hormones are essential for the proper growth and metabolism of the body. They directly affect the functioning of most of the organs in the body.

Thyroid disorders occur when the thyroid gland does not produce the right amount of hormones needed by the body.

To fully understand thyroid disorders, let us look into the structure and function of the thyroid gland.

Structure of the Thyroid Gland

The thyroid gland is a small bow-shaped gland that sits in front of the windpipe right below the larynx also known as the voice box. The thyroid gland has two lobes located on either side of the windpipe connected by a narrow strip of connective tissue called “isthumus”.

Detailed Diagram of the Thyroid Gland

Detailed Diagram of the Thyroid Gland

Hormones Produced by the Thyroid Gland

The three hormones produced by the thyroid gland are -

  • Thyroxine (T4)
  • Triiododthyronine (T3)
  • Calcitonin

The main hormone produced by the thyroid gland is the “Thyroxine” hormone also referred to as T4. Once Thyroxine enters the bloodstream, a small amount of the hormone is converted into “Triiododthyronine” referred to as T3.

Calcitonin is another hormone produced by the thyroid gland. Calcitonin reduces calcium levels in the bloodstream when the concentration of calcium is above the normal level.

The brain plays an important role in the proper functioning of the thyroid gland. When the thyroid hormone levels are low, the brain produces a hormone called “Thyrotropin Releasing Hormone,” also referred to as TSH. TSH stimulates the thyroid gland to produce more T4 when T4 levels are low.

Importance of Iodine

The main component of thyroid hormones is iodine. Iodine is very important for the proper functioning of the thyroid glands. Iodine cannot be produced by the body; it has to be absorbed from the nutrients that enter the bloodstream while digesting food.

Functions of the Thyroid Gland

The thyroid gland is responsible for the following functions in the body -

  • maintaining the body temperature
  • heart beating properly and the strength of the pulse
  • proper utilization of food
  • proper growth of the brain in children
  • overall growth in children
  • the quick response of the nervous system

What is Hyperthyroidism - Causes and Symptoms

Hyperthyroidism is a condition in which thyroid hormones in the blood are above the normal level. Hyperthyroidism occurs when there is an increase in the production of the thyroid hormone thyroxine.

A condition called Grave’s Disease is responsible for most hyperthyroidism conditions. Grave’s Disease occurs when the body fights against and attacks the thyroid gland. The thyroid gland responds to the attack by producing more thyroxine. When this happens, the thyroxine level in the blood shoots up above the normal level.

Sometimes hyperthyroidism can be because of a swollen thyroid gland or small growths in the thyroid gland called nodules.


  • sudden weight loss
  • the rapid increase in heartbeat
  • nervousness, anxiety
  • tremors
  • excess sweating
  • fatigue
  • menstrual irregularities
  • experience difficulty in sleeping
  • hair becomes thin and brittle
  • enlarged thyroid gland (goiter)

There are medications to cure hyperthyroidism. Hyperthyroidism can be life-threatening if it is not treated.

What is Hypothyroidism - Causes and Symptoms

Hypothyroidism is a condition that occurs when thyroid hormone levels in the blood are low. Hypothyroidism occurs when the thyroid gland does not function properly and produces enough thyroid hormones.

The main cause of hypothyroidism is a condition called "Thyroiditis." In this condition, the thyroid gland is swollen, inflamed, and does not produce enough thyroid hormones for the body to function properly.

Hypothyroidism can also be due to Hashimoto’s Disease, a condition in which the body attacks the thyroid gland and destroys it.

Other causes of hypothyroidism are -

  • effect of certain medication
  • birth defects
  • surgical removal of a part of the whole thyroid gland
  • pituitary tumor or surgery
  • treatment with radioactive iodine


Hypothyroidism may include the following symptoms -

  • fatigue
  • extreme sensitivity to cold temperatures
  • dry skin
  • puffy face
  • increase in weight without reason
  • muscle weakness
  • muscle stiffness and aches
  • swelling of joints
  • slow heartbeat
  • depression
  • irregular or heavy menstrual periods

When hypothyroidism is not treated, it may lead to a condition called myxoedema. Myxoedema occurs in advanced stages of hypothyroidism and can be life-threatening. Myxedema can lead to decreased blood pressure, decreased breathing, and decreased body temperatures.

There are tests to detect thyroid conditions. Medications are available for the treatment of thyroid disorders.


© 2013 Nithya Venkat


Nithya Venkat (author) from Dubai on February 22, 2017:

aesta1 thank you for your visit and comment.

Mary Norton from Ontario, Canada on February 20, 2017:

Some in our family has hypothyroidism so this is very enlightening.

Nithya Venkat (author) from Dubai on October 18, 2014:

lambservant thank you and am so happy you understood. You made my day and take care.

Lori Colbo from United States on October 17, 2014:

This was excellently written and researched - easy to understand too. I have hypothyroid and it's no fun. Medication has evened it out and I am doing well. It's nice to learn about it.

Nithya Venkat (author) from Dubai on September 12, 2014:

Pro-Hubber thank you for your visit and share. Much appreciated.

Pro-Hubber from Florida on September 11, 2014:

Very Informative, tweeted, shared in Google+, pinterest

Nithya Venkat (author) from Dubai on January 19, 2014:

cclitgirl thank you for stopping by, I hope my hub helped you understand. Take care.

Cynthia Calhoun from Western NC on January 19, 2014:

My sister has hypothyroidism and I always wonder if I might get it. That said, reading this was a nice refresher to know what signs to look for. Thanks - well-researched. ;)

Nithya Venkat (author) from Dubai on January 10, 2014:

teaches12345 many people suffer from these problems. Glad you are free from thyroid problems. Thank you for your visit.

Dianna Mendez on January 10, 2014:

I have overcome my thyroid problem with the use of natural iodine. It may not work for others, but it did the job for me. Thanks for covering this important topic with great detail. I know there are many out there that will benefit from your sharing.

Nithya Venkat (author) from Dubai on January 02, 2014:

DDE thank you for reading and leaving a comment, much appreciated.

Devika Primić from Dubrovnik, Croatia on January 02, 2014:

Thyroid Disorders - Hyperthyroidism & Hyporthyroidism is an informative and helpful hub to all readers.

Nithya Venkat (author) from Dubai on December 31, 2013:

Eiddwen thank you for stopping by, thanks for the vote too.

Wishing you a Happy New Year!!

Eiddwen from Wales on December 31, 2013:

Interesting and useful Vellur.

Voted up for sure and I wish you and yours a Happy New Year..


Nithya Venkat (author) from Dubai on December 31, 2013:

AliciaC thank you for your visit and yes they are unpleasant disorders.

Linda Crampton from British Columbia, Canada on December 30, 2013:

Thanks for sharing the useful information about two important and unpleasant disorders, Vellur.

Nithya Venkat (author) from Dubai on December 30, 2013:

Jackie Lynnley thank you for stopping by and reading. Thanks for the vote and share.

Jackie Lynnley from the beautiful south on December 30, 2013:

Some scary stuff, very well explained. Up and sharing.

Nithya Venkat (author) from Dubai on December 30, 2013:

Hariprasad thank you for reading and sharing your views with us, much appreciated.

Harish Mamgain from New Delhi , India on December 30, 2013:

Vellur, Hyper and Hyopo thyroid diseases have been explained by you in a very simple way. These diseases are very rampant these days. This article says that Grave 's disease and Hashimoto's disease are outcome of attacks of our own body. Strange are ways of our body. I think, may be hectic and reckless lifestyle plus bizarre food habits are also to blame for this. Really knowledgeable stuff.

Nithya Venkat (author) from Dubai on December 30, 2013:

Nell Rose thank you, it is appalling indeed how doctors do not have the knowledge that is so important to save precious lives. Thank you for the vote up. Take care. Wishing you a Happy New Year.

Faith Reaper thank you for reading. Thank you for the vote up. Wishing you a Happy New Year.

ChitrangadaSharan thank you for reading. As you say thyroid disorders have become very common. Thank you for the vote up too.

Chitrangada Sharan from New Delhi, India on December 30, 2013:

Very useful information about Thyroid disorders!

It has become a very common disorder nowadays, especially among women. Thanks for explaining the causes and symptoms to watch out for.

Voted up as useful! Thanks!

Faith Reaper from southern USA on December 30, 2013:

Insightful article here on thyroid function! Thank you for sharing what to watch for in such a condition.

Up and more and sharing

Happy New Year.

Faith Reaper

Nell Rose from England on December 30, 2013:

Great explanation of thyroid function vellur, I have both hyper and hypo thyroid, and yes it can be really dangerous, especially when the Docs know nothing about it! I wrote about it, its appalling how doctors don't learn about it properly and how dangerous it can be, voted up!

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