An Introduction to Thyroid Health

Your thyroid gland (a.k.a. The Master Gland) is responsible for regulating the metabolism of every hormone in your body via a complex closed-loop feedback process. It produces 4 thyroid hormones  and calcitonin, in response to signalling from the pituitary gland. (T1, T2, T3, T4 are each named for the number of iodine atoms per molecule)

The thyroid hormone that is critical for life is T3 (triiodothyronine) which serves to increase the body’s oxygen and energy consumption. It is responsible for helping to regulate appetite, glucose and fat burning, protein synthesis, brain function, growth, reproduction, sleep, body temperature, heart rate and blood pressure; without any one of these functions we would not be able to survive.

As T3 is so powerful the thyroid also produces the less active T4 (thyroxine) which has a longer “shelf life” in the blood stream and can be converted into T3 as-and-when necessary at various sites in the body such as the liver, gut and kidneys. This is done by removing one of the iodine atoms from the molecule.

A Basic Summary of Thyroid Hormone Balance

When the pituitary gland (located at the base of the brain) senses low thyroid hormones it produces Thyroid Stimulating Hormone (TSH) which signals the thyroid to produce thyroid hormones.

The thyroid (a butterfly shaped gland located in the neck) then produces both a small amount of T3 hormones for immediate use and a higher proportion of T4 hormones for converting to T3 when necessary.

T3 is taken up by your cells for various metabolic processes, such as those listed above.

Some of the T4 is gradually converted to T3 (so that cells have a constant supply floating around in the bloodstream) and whatever is left over converts to Reverse T3 (RT3) which functions to neutralise any excess T4 floating around (unchecked T4 would result in symptoms of an overactive thyroid.)

When the T3 and T4 levels are low again, the pituitary gland produces new TSH.

How are Thyroid Conditions Diagnosed?

A medical practitioner should be alerted to an imbalance in thyroid health by the number and severity of symptoms you have. A quick internet search will call up a vast array of symptoms associated with an overactive or an underactive thyroid and so I will not list them here.

Swelling of the thyroid may be a visible indicator of inflammation. In addition, your basal body temperature parameters can give you an idea of whether you have hypothyroidism (underactive thyroid) or hyperthyroidism (overactive thyroid.)

If your medical practitioner suspects a thyroid issue they will probably request blood tests to measure how much TSH you have in your system. While this won’t give you an accurate picture of whether your thyroid is producing adequate T3 and T4; if the conversion from T4 to T3 is happening or if your cells are actively taking up the T3; it will at least indicate if your pituitary is pumping out more or less TSH than within “normal parameters” and therefore if you are likely to be hyperthyroid or hypothyroid.

If you are in a position to get private blood testing you might be able to request a far more accurate picture from having your T3, RT3 and T4 levels assessed in addition to your TSH levels.

How are Thyroid Conditions Conventionally Treated?

The most common treatment for an underactive thyroid is to have T4 prescribed.

Hypothyroid conditions are sometimes caused by an autoimmune disease such as Hashimoto’s, in which the immune system produces antibodies that attack the thyroid gland. Sometimes a medical practitioner will also prescribe T3 and/or desiccated thyroid in response to the presence of specific Hashimoto’s indicating antibodies in the blood.

Hyperthyroid symptoms such as palpitations may be treated directly or the thyroid itself may be treated with chemical blockers to reduce the amount of thyroid hormones produced. If neither of these are effective then there are more invasive interventions available such as thyroid surgery or the use of radioactive iodine.

Hyperthyroid is sometimes caused by an autoimmune condition such as Grave’s, in which the immune system produces antibodies that turn on the thyroid and cause it to grow and go into overproduction. Thyroid surgery or radioactive iodine are are more likely treatments in these cases. It is worth noting that Hashimoto’s may also cause hyperthyroid conditions.

How Can Thyroid Health be Supported with Diet?

As a health and nutrition coach I do not treat the thyroid directly, but I do offer highly individualised client advice that helps support the entire system. For instance:

  • Supporting balanced cortisol levels directly supports thyroid function.
  • Supporting gut function enables the gut in its conversion of some of the T4 to T3.
  • Supporting liver function enables the liver in its conversion of some of the T4 to T3.
  • Optimising levels of all micronutrient and macronutrient intake provides the material necessary to produce all hormones within the body, including those of T3 and T4.

If you are interested in finding out how my health and nutrition coaching may be of benefit to you please contact me here.