Thyroid Disorders Community
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My friend taken thyroid test they said 6.4

Can u please tell me what is the normal level of thyroid ... 6.4 is normal or what?
8 Responses
Avatar universal
First off you must know what test this is. There are several tests that can be done for Thyroid.  

Without any detail about the test itself, the most likily test that was done was the TSH test.  The "normal" ranges vary for this.  However more than 10 Years ago the American Academy of Clinical Endochrinologists recommended that the upper or high end of the range be 3.0.  And anything above this level should be considered for thyroid treatment.

Understand that TSH is a inverse relationship.  That means that a "high" result means that the person is LOW in thyroid.

However this is all an assumption and further testing should be done to include the two ACTUAL thyroid hormones which are:

Free T4 (FT4) and Free T3.

if thosse tests have not been done, I would recommend that they be done IF your friend is symptomatic.

How does your friend feel?

Can you get your friend to come here for himself/herself rather than having to relay everything.
Avatar universal
She is Good.... we have done all tests .. Can i forward the reports to you
Avatar universal
tsh alone says nothing. if your free t3 and free t4 are under normal range then you have subclinical hypothyroidism which doesn't require any treatment unless the tsh go above 10.
649848 tn?1534633700
As des900 said, TSH, alone says nothing...

TSH does "not" have to be above 10 to require treatment for any kind of hypothyroidism... If Free T3 and Free T4 are below normal or in the low normal ranges and symptoms of hypothyroidism are present, treatment with replacement thyroid hormones should be initiated.

Testing should also be done for thyroid antibodies to determine whether or not the person has Hashimoto's Thyroiditis, which is an autoimmune thyroid condition that destroys the thyroid. Those antibody tests are Thyroid Peroxidase Antibodies (TPOab) and Thyroglobulin Antibodies (TgAb)...

Avatar universal
des900    It is ridiculous to say that hypothyroidism doesn't require treatment unless the TSH goes above 10.  And subclinical hypothyroidism is defined as a TSH between the upper range limit and 10.  In those cases, a Free T4 test is done and compared to its reference range.  In the unusual case that the Free T4 is below range, then treatment is initiated.  Unfortunately, due to the erroneous assumptions used in establishing the FT4 range, hypo patients with hypo symptoms frequently fall within the lower half of the range.  Then the doctor has to decide whether to treat or not.

ratishk   A TSH of 6.4 is officially classified as subclinical hypothyroidism, requiring more information in order for the doctor to make a diagnosis.  The additional tests should be for Free T4 and Free T3 (not the same as Total T4 and Total T3).  Also to determine if the cause for the high TSH result is Hashimoto's Thyroiditis, two tests should be done to test for the antibodies of Hashi's.  They are TPO ab and TG ab.  

The most important question regarding any treatment with thyroid medication is whether your friend has symptoms of being hypothyroid.  You can see 26 of the most typical symptoms in this link.
Avatar universal

Initiating levothyroxine replacement therapy is recommended for all patients with a TSH greater than 10 mIU/L, even if the free thyroxine concentration is within normal laboratory range. However, treatment of patients with a serum TSH level between 5 and 10 mIU/L remains controversial.
Avatar universal
Serum TSH Concentration of 5.1 to 10 mIU/L

Large-scale randomized studies to conclusively show reduction of cholesterol with levothyroxine therapy in this subgroup are lacking. Most studies are not stratified for different categories of serum TSH levels, and although benefits for symptoms and lipid levels have been shown for mild thyroid failure as a group, results cannot be extended to most patients with SCH who are in this subgroup.1,45 One study of TSH levels of 5.0 to 10.0 mIU/L did not show any benefit.
Avatar universal
A person's thyroid status is the result of tissue thyroid effects.  Hypothyroidism occurs when tissue thyroid levels and the many cofactors that affect tissue thyroid effects are reduced and body functions are diminished.  A TSH test is totally inadequate as the primary diagnostic for the thyroid status of a patient.  Each person has his own thyroid process set point at which they feel best.  Also, individual reference ranges based on the individual's test results are approximately half the reference ranges for a group of people, for all thyroid tests.    Also the group range limit for TSH has been set high enough to avoid false positive diagnoses, but has caused many more false negative diagnoses, with resultant suffering by patients.  Further studies have shown that TSH did not correlate well with either Free T4 or Free T3, much less correlate well with symptoms, which is the patient's concern, not test results.  

Hypothyroidism is not just an under active thyroid gland resulting from autoimmune system disorder.  It can also be a dysfunction of the hypothalamus/pituitary system resulting in inadequate stimulation of the thyroid gland by TSH, which is called central hypothyroidism.  It can also be caused by excessive conversion of T4 to Reverse T3.  Also, with age, the Free T3 sometimes drops low enough to cause hypo symptoms.  There are also cofactors which affect transport of serum thyroid hormone into the organs and cells of the body, so that serum thyroid levels sometimes do not adequately reflect tissue thyroid levels.  There are also cofactors that affect how thyroid hormone is metabolized.  So the bottom line is that hypothyroidism has a wide range of potential causes, and it occurs when one or more of these conditions result in inadequate metabolism of tissue thyroid hormone, with resultant diminished body functions.  The number of variables and  cofactors between tissue thyroid effects and a TSH, and the negligible correlation between the two clearly shows the futility of TSH as a diagnostic other than to identify overt hypothyroidism (TSH >10), and to distinguish between primary and central hypothyroidism.  

When a serum TSH test exceeds the range limit, then a  Free T4 test is initiated.  If the Free T4 test falls within its range (which has somehow become accepted as "normal"), then treatment is usually denied.  So the validity of that reference range is a major concern.  Unfortunately the ranges for Free t4 (and also Free T3) are not based on large data bases of healthy adults with no thyroid pathology.  Instead the ranges are based on all test data  at a given lab, excluding only data from patients with TSH exceeding its reference range.  That means that sick people, people with central hypothyroidism, and patients taking thyroid hormone are all included in the data base.  Accordingly Free T4 and Free T3 reference ranges are flawed at the low end and test results in the lower half of the ranges should be cause for further evaluation, not denial of treatment.  Due to the intervening processes between serum Free T4 and tissue thyroid effects, free T4 also has minimal correlation with tissue thyroid effects such as symptoms.  

So, just following general Guidelines that prescribe lab tests and reference ranges without knowledge of the patient is a violation of both common sense and fundamental mathematical principles.   This is why numerous scientific studies have concluded that diagnosis and treatment of thyroid insufficiency should be based on clinical criteria--according to the patient's signs and symptoms first, and the FT4 and FT3 levels second.
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