Thyroid GIB
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GX11 1AA
Gibraltar
Local Mobile 54009628 Email thyroidgib@gmail.com
01
The Blood Test
THE BLOOD TESTS (Thyroid Function Test)
The blood test for thyroid problems is called a Thyroid Function Test. The most usual tests are:
TSH, TT4 AND FT4
There is a range, which is used for the tests. These vary sometimes which is why you must always
ask what the range is, so that you can see where you are in the range.
TSH = THYROID STIMULATING HORMONE
This hormone comes from the pituitary to stimulate the thyroid gland into making more hormone.
TSH rises when the thyroid is struggling.
The approx. reference range for this test is 0.4 to 4.5.
TT4 = TOTAL T4
Thyroid hormones bound to proteins. TT4 lowers when the thyroid is struggling.
The approx. reference range for this test is 50 to 160.
FT4 = FREE T4
Thyroid hormones not bound to proteins. FT4 lowers when the thyroid is struggling.
The approx. reference range for this test is 10 to 24
FT3 = FREE T3
T4 converts to T3 and is the only thyroid hormone actually used by the body’s cells.
The approx. reference range for Free T3 is 4 to 8.3
We at Thyroid GIB believe that you need to know your Free T3 level too because this will often
show low if you are not converting, and high if you have blocked receptor cells. Even if you are
converting, the body needs the extra T3 that a normal thyroid produces. There has been some
research to show that people feel better on a mixture of Thyroxine (T4) and Triiodothyronine (T3).
Effects of Thyroxine as Compared with Thyroxine plus Triiodothyronine in patients with
hypothyroidism – The New England Journal of Medicine Feb.11, 99 Vol. 340.
With all of these tests, your results could be anywhere within the range and you would be classed
as “normal”. If you are at the very edge of the range, either at the bottom or at the top, you could
be classed as “borderline”. Neither you nor your doctor truly knows what your normal is, if you did
not have a blood test done before you became ill. There are also particular reasons why the blood
tests remain in the normal range. If you are not converting from T4 to T3 or if your cells are not
taking up the T3 normally, your T4 levels and your TSH levels will still show as normal.
The Broda Barnes Foundation tell us “Dr Barnes found that the primary reason for the inaccuracy of
the blood tests for thyroid function is that the thyroid hormones are not utilized in the blood, but
are utilized intracellularly. Therefore a patient can have enough thyroid hormones circulating in the
blood to give a “normal” reading, but if the hormones are not getting into the cells, the patient will
be hypothyroid.
Also, there is a problem of low blood volume in hypothyroid patients. This means that any blood
test value will appear higher than it actually is because the patient has a lower than normal blood
volume. In many patients with “normal” or “high” thyroid blood levels, but many clinical symptoms,
the patient’s blood levels actually drop lower once the patient is given thyroid hormones simply
because their blood volume increases.
NB: Dr Bayliss tells us in his book Thyroid Disease: the facts “Do not take any thyroxine on the day
when you go for your check-up and have a blood sample taken. The reason for this is that for
about 4 hours after ingesting a tablet of thyroxine, the blood level of thyroxine peaks and will give
a spuriously high reading”. Other doctors I have asked tell me that it makes no difference. You
decide!!
TAKEN FROM MEDICINE INTERNATIONAL 1993
“The aim of thyroxine replacement therapy is to normalise plasma TSH and to achieve a clinically
euthyroid state. To obtain this, FT4 and TT4 have to be maintained at, or just above, the
upper reference interval”.
NB: Dr. Toft, Consultant Physician, states in the British Thyroid Foundation newsletter Issue No. 23
that normal ranges are: T4 (10 – 25) and TSH (0.15 – 3.5). He also states that “the correct dose is
that which restores good health; in most patients this will be associated with a level of T4 in the
blood towards the upper part of the normal range or even slightly high and a TSH level in the blood
which is in the lower part of the normal range.
MYXOEDEMA
Myxoedema is the medical term for severe hypothyroidism.
Mucopolysaccharides – Gel-Like Substance.
Myx = mucin (gel-like) - Oedema = swelling.
The body makes mucopolysaccharides in normal quantities. When the thyroid is malfunctioning,
they are mass-produced. Hence the bloated look that patients sometimes have. These
mucopolysaccharides infiltrate into all the connective tissues and cause many problems i.e. joint
pains and muscular pains. Did you know that the thyroid becomes more effective in the summer? So if your symptoms come back a bit in the winter, you may need a slightly higher dosage of your hormone replacement.
This information is not intended to be a substitute for medical guidance from your own doctor. Thyroid GIB cannot be held responsible for any actions taken as a result of using Thyroid GIB resources. Please check with your personal physician before applying any of these recommendations.