The thyroid is a gland in your neck that is necessary for the healthy function of all the cells in your body. The thyroid gland takes in iodine from the food you eat and converts it to two hormones; T3 (Triiodothyronine) and T4 (Thyroxine). These hormones are then released into your bloodstream and are responsible for the healthy function of nearly every cell in your body.

It’s vital that T3 and T4 levels remain stable; not too low or too high. Your thyroid regulates your body’s biological functions:

  • Breathing
  • Heart rate
  • Nervous system
  • Body weight and metabolism
  • Cholesterol levels
  • Muscles
  • Menstrual cycles
  • Body temperature

The thyroid gland is controlled by the pituitary gland, a small gland located at the base of the brain. The pituitary gland senses when T3 and T4 levels change and releases TSH (Thyroid Stimulating Hormone) which stimulate the thyroid to produce more or less of T3 or T4 to keep each amount balanced. Most T3 binds to proteins in your body, with some T3 circulating around in your blood; this T3 is called free T3.

Elevated levels of T3 could be a sign of a number of thyroid related disorders:

  • Hyperthyroidism
  • Graves’ disease
  • Painless or silent thyroiditis
  • Thyrotoxic periodic paralysis
  • Toxic nodular goiter

They could also be a sign of high levels of protein in the blood and in rare cases, thyroid cancer or thyrotoxicosis. Pregnant women or people suffering from liver disease will normally have elevated levels of T3.

Decreased levels of T3 occur when you are sick. People with long term illness or who are seriously ill will have low T3 levels but low T3 can also be a sign of hypothyroidism or starvation.

It’s important to remember that birth control pills and steroids can also affect T3 levels.

In general, a blood test to check thyroid function will test for T3, T4 and TSH (thyroid stimulating hormone), the hormone that stimulates the levels of T3 and T4.

A thyroid disorder can manifest in a variety of ways, with varying symptoms, making it difficult to diagnose without a blood test. Hypothyroidism is a condition where your thyroid is underactive and is a relatively common condition. Most cases of hypothyroidism are caused by the immune system attacking the thyroid gland and damaging it. In most cases, it is easily treated with a pill like Cytomel Tabs (Liothyronine or T3). If your thyroid is overactive the condition is called hyperthyroidism and is also a relatively simple condition to treat with medication.

Women tend to suffer more from thyroid problems than men, but anyone of any age can be affected. Some thyroid disorders are hereditary and they can be temporary or permanent. They are common and can remain undiagnosed, fortunately once diagnosed they can be treated and long term medication can solve most thyroid conditions.