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Thyroid 101 - understanding how the thyroid gland works.

It’s important to have a basic understanding of how the thyroid gland works and the hormones it produces. It can maybe give you an idea on why you are experimenting mysterious symptoms and help you ask the right questions when you visit your Dr.




Here's how your thyroid works

The pituitary gland in your brain produces and releases : Thyroid Stimulating Hormone (known as TSH) into the bloodstream. TSH then triggers your thyroid to produce T4 and T3. About 80% is T4 and 20% is T3.

However, your body must convert T4 into T3 (the active form) in order to use it.

If the conversion of T4 to T3 is poor, then you may experience some symptoms like fatigue, depression, loss of hair, poor concentration or gaining weight for no reason.


Note that this poor conversion can occur even if your TSH levels appear to be in the norm,

and that most traditional health practitioners often screen only TSH.

To find the root cause of your symptoms and optimize thyroid function it’s important to assess the conversion of T4 to the active form of T3!

T3 and T4 affect every single cell in your body

  • Regulates energy and metabolism.

  • Affects weight loss or weight gain.

  • Monitors the rate at which your body uses calories.

  • Monitors heart rate as well.

  • Influences your digestive system.

  • Brain health.

  • Regulates body temperature.

  • Controls muscle contraction.

There are several problems with using ONLY TSH to assess thyroid function.

it’s not sufficient on its own because:

  • It’s NOT measuring actual thyroid hormone levels.

  • Or how well thyroid hormones T4 and T3 are being produced.

  • Or how well T4 is then converted to its active form (T3) …

  • And, finally, how well the tissues are using the thyroid hormone at the cellular level to drive metabolism.

NB : TSH cannot detect thyroid hormone RESISTANCE, which is when receptor sites are malfunctioning and the cells are unable ‘let it’ the hormones.

Final thoughts

  • it's important to check a full thyroid panel (TSH, T4, T3, thyroid antibodies, etc).

  • check deficiencies (iodine, iron, selenium, zinc)

  • and the gut, liver, stress axis have major roles in thyroid health, as well.


more to come :-)

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