What does your thyroid do?

Approximately 1 in 20 people has some kind of thyroid disorder, which may be temporary or permanent.

Your thyroid is a gland and is located in your throat just below your larynx - it is indicated as an orange glow on the illustration opposite.

What does the thyroid gland do?

The following two hormones are secreted directly into the bloodstream by the thyroid gland:

1. Thyroxine - this hormone contains four atoms of iodine and is referred to as T4.
2. Triiodothyronine - this hormone contains three atoms of iodine and is referred to as T3.

Your body converts T4 into T3 in your cells and tissues.  It is the T3 hormone (either made from the T4 or secreted directly from the thyroid gland) which is biologically active and influences the activity of cells and tissues of your body. 

The two hormones regulate the speed at which your body cells work

Thyroxine and Triiodothyronnine regulate the speed with which your body cells work i.e. influence your metabolism. This is how it happens:

1. The thyroid secretes the T3 and T4 hormones
2. The hormones get into your blood stream and are transported around they body
3. While travelling around they communicate to every one of your cells if it needs to be consuming more or less oxygen and nutrients.

The amount of hormones produced by the thyroid is very important as too much or too little can cause significant health issues and be debilitating to the sufferer. The two conditions and their symptoms are described below:

Under-active thyroid (Hypothyroidism)

An under-active thyroid is diagnosed when not enough Thyroxine is produced for the body’s needs. As a result cells and organs of your body slow down. Typical symptoms of an under-active thyroid condition include:

• Feeling cold
• Weight gain
• Poor concentration
• Tiredness
• Depression
• Slow heart rate
• Sluggish intestines (constipation)

Overactive thyroid (Hyperthyroidism)

An overactive thyroid is diagnosed when too much Thyroxine is produced for the body’s needs. As a result the body cells work faster than normal. Typical symptoms of an overactive thyroid include:

• Heat intolerance
• Weight loss
• Anxiety
• Sore eyes
• Fast heart rate
• Increased intestine activity (diarrhoea)

Thyroid conditions are treatable so if you feel you exhibit the symptom patterns above you should consult your doctor who can run tests for a proper diagnosis.