By Louise O'Connor, Naturopath + Wellness Coach
You may be told you have normal thyroid levels despite the fact you are experiencing symptoms of an underactive thyroid.
Could it be possible to have an underactive thyroid even though your thyroid blood test result is in the 'normal' range?
The 'TSH First' Testing Strategy. Is A Single Test Of TSH Enough?
A TSH test is routinely used to assess your thyroid health. A TSH test measures the amount of thyroid stimulating hormone (TSH) in your blood.
What is TSH?
TSH is not actually produced by the thyroid. TSH is made in the pituitary gland which is located within the brain. When TSH is released by the pituitary it travels to the thyroid where it triggers the thyroid to make important thyroid hormones.
The two main thyroid hormones produced by the thyroid are thyroxine (T4) and triiodothyronine (T3).
The TSH reference range used by pathology labs is just that; a general reference range. It is derived from average values in the whole population. Having a result in the reference range does not always mean your thyroid is working well.
For example, if you are at the higher end of the range you could have borderline hypothyroidism. Based on the most up to date research a TSH of less than 2.0 mU/L is ideal.
An abnormal TSH usually indicates a deficiency or an excess of thyroid hormones available to the body but it does not indicate the reason why. An abnormal TSH result is usually followed by further testing of free T4 and free T3 to investigate the cause.
Your TSH lab result should also be considered along with how you feel. Are you experiencing the typical signs and symptoms of an underactive thyroid?
The standard references listed here are used by Australian pathology labs. If you are outside of Australia you may have different reference ranges. Please discuss these with your health practitioner.
Standard Thyroid Lab Levels: Normal Reference Ranges
TSH: Normal range 0.4-5.0 mIU/L.
All too often individuals are told their thyroid is normal without being screened for possible autoimmune activity within the thyroid. Known as the thyroid peroxidase antibody test this is one of the most important thyroid tests to perform.
Why is this test so important?
A test of thyroid antibody levels can establish a possible diagnosis of an autoimmune thyroid disorder. The higher the level, the more likely this is occurring. Autoimmune problems occur when the immune system malfunctions and the body attacks its own tissue.
Elevated levels of thyroid antibodies usually indicate a low thyroid disorder called Hashimoto’s thyroiditis. This chronic inflammatory thyroid disorder is one of the leading causes of hypothyroidism, especially in women.
Hashimoto's thyroiditis was first described by the Japanese specialist Dr. Hashimoto Hakaru in 1912. This autoimmune reaction associated with Hashimoto's thyroiditis creates excess inflammation within the gland and, in some cases eventual destruction of the thyroid.
In summary, a comprehensive thyroid panel is ideal and this includes testing TSH, free T4, free T3 and screening for Hashimoto’s thyroiditis with a test of thyroid antibodies.
Low Thyroid Function Impacts On Whole Body Health
Do You Have Low Thyroid Symptoms?
Normal Thyroid Levels? It Could Also Be Reverse T3 Dominance
Copyright © 2016 Wellness Coaching Pty Ltd. Australia. All rights reserved.