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What Does the Thyroid Do?

what is the thyroid

The endocrine system is composed of various glands, one of which is the thyroid. Shaped similar to a butterfly, the thyroid gland consists of two separate lobes that are connected by a piece of tissue on either side of the windpipe. It is located in the neck around the trachea. 

What Hormone Does the Thyroid Gland Produce?

The main function of the thyroid gland is to convert iodine, which is found in many foods, to  two hormones, triiodothyronine (T3) and thyroxine (T4). The thyroid is responsible for all metabolic activity in the body including:

  • Regulating a person’s metabolism
  • Regulating heart rate 
  • Maintaining the gastrointestinal tract
  • Stimulating mitochondria, which are the energy production centers of cells
  • Regulating a person’s appetite

How is the Thyroid Gland Regulated?

Because the thyroid is responsible for maintaining so many functions in the body, it needs to be regulated. The thyroid gland is controlled by the pituitary gland, which is a peanut-sized gland in the base of the brain. When the level of T3 and T4 drop, the pituitary gland produces a thyroid stimulating hormone (TSH) which stimulates the thyroid to produce enough hormones.

What Happens if the Thyroid isn’t Regulated?

The two most common problems that affect the thyroid are:

  • Hyperthyroidism Hyperthyroidism causes your thyroid to make too much thyroid hormone, which may result in weight loss, rapid heart rate and mood swings. If hyperthyroidism is detected by a physician after a thyroid hormone test, you will begin antithyroid medicines.
  • Hypothyroidism Hypothyroidism is caused by too little thyroid hormone being secreted by the thyroid. It may cause people to feel sluggish and can cause a decrease in metabolism. The most common way to treat hypothyroidism is with the synthetic thyroid hormone T4.

Thyroid Diseases: Symptoms and Remedies

thyroid diseases


Our thyroid gland is a gland which is present in the neck. It produces thyroid hormone that affects many body functions and metabolism.


Hypothyroidism, or underactive thyroid, results from reduced effects of thyroid hormone on tissues.

People at higher risk of hypothyroidism include:

  • those who have a personal or family history of autoimmune disease
  • women after pregnancy
  • those with a history of head/neck radiation
  • people who are of an age greater than 65 years.

The symptoms of hypothyroidism are:

  •  fatigue
  • cold intolerance
  • weight gain
  • constipation
  • menstrual irregularities
  • dry skin
  • brittle hair

A blood test will help with the diagnosis and the treatment is a thyroid hormone supplement which is taken on an empty stomach. A half to one hour before breakfast is best for optimal absorption.


The other side of the spectrum is Hyperthyroidism, or overactive thyroid, which results from too much thyroid hormone on tissues.

The signs and symptoms of hyperthyroidism are:

  •  fatigue
  • feeling hot
  • sweating
  • frequent bowel movements
  • weight loss

Hyperthyroidism may also sometimes affect the eyes, producing eyelid retraction and stare.

Untreated hyperthyroidism can cause atrial fibrillation (irregular heart beat), high blood pressure and loss of bone mass over time. If hyperthyroidism is diagnosed by a blood test,  then the treatment is with anti-thyroid medication. Definitive treatment is by radioactive ablation of the thyroid or thyroid surgery.