Read your THS Blood Results in 5 minutes (Easy Way)

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How to interpret a THS blood test evaluating the thyroid at home?

It’s not easy to interpret blood results that often leave us perplexed.

Also, it may be interesting to try to decode these numbers that you have in front of you, asking yourself what is behind this anomaly that the laboratory has highlighted.

Let’s try to see it more clearly together and decipher it calmly.

The thyroid function

The thyroid is an endocrine gland located in the middle of the neck.

It produces two hormones:

  • T4 hormone or Tetra-iodothyronine
  • T3 hormone or Triiodothyronine

The levels of these hormones are regulated and controlled by TSH or thyroid-stimulating hormone.

TSH is produced by the pituitary gland located in the brain.

In short, when T3 and T4 levels are reduced, they send a signal to the brain and pituitary gland or hypophysis then begins to produce the TSH hormone which will help rebalance the T3 and T4 hormones.

When T3-T4 levels are insufficient, TSH levels rise.

This basic information will help us interpret your THS blood test results.

thyroid blood test abnormal

Thyroid blood test

All laboratory blood tests include 3 essential dosages:

– T3 levels
– T4 levels
– TSH levels


  • T3 hormone levels

Your analysis mentions a T3 level equal to 72.5 nanograms per deciliter.

Besides this evaluation, you will find the biological reference values ​​indicating the expected normal T3 level.

For adults aged 20 to 50, the norm is between 70 and 204 nanograms per deciliter.

Beyond 50 years, they must evolve between 40 and 181 nanograms per deciliter.

Standards for pregnant women follow:

– first quarter: 81 to 190
– in the second quarter: 100 to 260
– in the third quarter: 100 to 260

And finally, you find the standards for children:

– from 1 to 5 years: 100 to 260
– from 5 to 10 years: 90 to 240
– from 10 to 20 years: 80 to 210


  • T4 hormone levels

This time, your test indicates that your T4 level is assessed at 8.3 micrograms per deciliter.

You also find next to the biological reference values:

– For adults, the standard varies between 3.2 and 12.6 micrograms per deciliter.

– For ages,

– 1-12 months: 6.1-14.9
– from 1 to 3 years old: 6.8 to 13.5
– from 3 to 10 years old: 5.5 to 12.8


  • TSH level

Your test indicates a TSH level of 2.65 micro international units per milliliter.

Still next to this result, you will find the biological reference values:

– 21 weeks to 20 years: 0.7 to 6.4
– from 21 to 54 years old: 0.4 to 4.2
– from 55 to 87: 0.7 to 8.9

You also find values ​​for pregnant women:

– first quarter: 0.3 to 4.5
– in the second quarter: 0.5 to 4.6
– in the third quarter: 0.8 to 5.2


  • Your thyroid test results

Your blood test results show that your T3, T4, and TSH levels are completely normal.

thyroid blood test levels

THS blood test results explained

Let’s imagine different scenarios to assess thyroid function abnormalities.


– Primary Hypothyroidism

T3 and T4 levels are insufficient.
TSH is high.

This is a typical case of primary hypothyroidism.

This case is very common and your physician will recommend certain medications.


– Secondary hypothyroidism

T3 and T4 levels are insufficient.
TSH level is normal.

Clearly, there is a problem with the pituitary gland which is not responding.

This is called secondary hypothyroidism.

Your physician will refer you to an endocrinologist for a better diagnosis.


– Subclinical Hypothyroidism

T3 and T4 levels are normal.
TSH is high.

This is subclinical hypothyroidism.

Your physician will order regular check-ups for monitoring, but you do not need treatment.

Physical activity and some changes in your diet will be required.


– Primary Hyperthyroidism

T3 and T4 levels are high.
TSH level is too low.

This is primary hyperthyroidism that requires treatment.


– Subclinical Hyperthyroidism

T3 and T4 rates are normal.
TSH level is too low.

This is subclinical hyperthyroidism.

Your physician will perform observation and depending on the following results, treatment may be required.

Thyroid test results chart


Thyroid Blood Test Results
Rate T3 – T4 TSH rate Diagnosis Processing
Too Low


T3 Less than 70
T4 less than 3.2


TSH greater than 8.9

Primary Hypothyroidism Drugs
Too Low


T3 less than 70
T4 less than 3.2


TSH between 0.4 and 8.9

Secondary Hypothyroidism Endocrinologist


T3 between 70 and 204
T4 between 3.2 and 12.6


TSH greater than 8.9

Subclinical Hypothyroidism Watch


T3 greater than 204
T4 greater than 12.6

Too Low

TSH less than 0.4

Primary Hyperthyroidism Drugs


T3 between 70 and 204
T4 between 3.2 and 12.6

Too Low

TSH less than 0.4

Subclinical Hyperthyroidism Observation

How do you know if you have hyper or hypothyroidism?

→ Primary hypothyroidism shows that the TSH level is increased.

It most often corresponds to an autoimmune disease, and in particular Hashimoto’s thyroiditis.


→ Secondary hypothyroidism shows that the pituitary gland does not secrete a sufficient amount of TSH.

It is however quite rare.

It requires support from an endocrinologist.


→ Subclinical hypothyroidism shows mild to moderate thyroid insufficiency that requires monitoring for its evolution.


→ Primary hyperthyroidism shows an excess of T3 and T4 hormones and a decrease in TSH.

It corresponds to an autoimmune disease, most often Graves disease, or reflects the presence of thyroid nodules or inflammation of the thyroid, thyroiditis.


→ Subclinical hyperthyroidism results in too low TSH levels without elevation of T3 – T4 hormones.

Regular monitoring should be implemented as this anomaly is likely to disappear.

Less than 10% of affected patients will progress to frank hyperthyroidism.

Frequently Asked Questions

THS blood test on an empty stomach or not?

Performing a TSH test does not require any particular restrictions.
So you don’t have to be fasting.

What is the turnaround time for the result of a TSH blood?

Blood test results are usually very quick.
If the sample is taken in the morning, you will have the results in the afternoon.
Most labs now offer an internet service allowing you to view them online as soon as they are ready.

What is the ultra-sensitive TSH test?

The ultra-sensitive TSH blood test is intended to determine the underlying cause of abnormal thyroid hormone levels.
It also helps to assess the exact functioning of the thyroid gland and estimate whether it is overactive or underactive.

Why measure TSH in the morning?

It is indeed advisable to take the blood sample for the TSH test in the morning.
A study has shown that the results differ enormously between a blood test carried out in the morning and in the afternoon.
It even specifies that 50% of thyroid problems are not diagnosed with an afternoon sample.

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Natural health is paramount to me, natural remedies have always been part of my life. Whatever the problem, I make sure to find natural solutions that can often be associated with traditional medicine. Everything I write here allows me to share them with you.

The content of this article is not intended to replace medical advice or any treatment.
Keep in mind that you should contact your doctor or any qualified healthcare professional to determine if you can add a supplement to your treatment or change your diet.

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