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LE Magazine November 2002
Defying the
Reference Ranges
When physicians review a patient’s blood test results,
their only concern is when a particular result is outside the
normal laboratory “reference range.” The problem is
that standard reference ranges usually represent
“average” populations, rather than what the optimal
range should be to maintain good health.
The lethal consequences of faulty reference ranges have
been discussed for many years in Life Extension magazine. As
more studies show that a person’s health can be severely
impaired when physicians rely on standard reference ranges, it
becomes imperative for Life Extension members to educate
themselves about “optimal” ranges to avoid becoming
a victim of medical ignorance.
It now appears that most standard reference ranges are too
broad to adequately detect health problems or prescribe
appropriate therapies on an individual basis.
An example of flawed reference ranges can be seen in blood
tests used to assess thyroid status. A long-standing
controversy has been how to best diagnose thyroid deficiency.
Conventional doctors rely on thyroid blood tests, whereas
alternative physicians also look for other signs and symptoms
of thyroid deficiency. A recent article in The Lancet reveals
surprising new findings about reference ranges that may shake
up current theories about assessing individual thyroid
status.
Before discussing The Lancet article, the reader should be
acquainted with the serious consequences of a thyroid hormone
deficiency. Aging people encounter a variety of ailments that
doctors often attribute to problems other than thyroid
deficit. Some of the most noticeable symptoms caused by low
thyroid are poor concentration, memory disturbances, cold
hands and feet, accumulation of excess body fat, difficulty in
losing weight, menstrual problems, dry skin, thin hair and low
energy. Some specific disorders related to thyroid deficiency
include depression, elevated cholesterol, migraine headaches,
hypertension and infertility.[1-9]
Broda O. Barnes, M.D., Ph.D. was a physician-scientist who
dedicated more than 50 years of his life to researching,
teaching and treating thyroid and related endocrine
dysfunctions. In his book entitled, Hypothyroidism: The
Unsuspected Illness, Dr. Barnes described over 47 symptoms
that may be related to poor thyroid function. During his many
years of research and practice, Dr. Barnes condemned
conventional doctors who ignored obvious clinical
manifestations of thyroid deficiency. According to Dr.
Barnes:
| “The development and use of
thyroid function blood tests left many patients with
clinical symptoms of hypothyroidism undiagnosed and
untreated.” |
In lieu of blood tests, Dr. Barnes advocated that patients
measure their temperature upon awakening. If the temperature
is consistently below normal ranges, this is indicative of a
thyroid deficiency. The box below provides specific
instructions on how best to measure your body temperature in
order to assess your thyroid hormone status.
Dr. Broda Barnes believed that 40% of the adult population
suffers from thyroid deficiency. Based on the percentage of
adults now taking prescription drugs to treat depression,
elevated cholesterol, high blood pressure and other
conditions, Dr. Barnes’ observations about the epidemic
of thyroid deficiency may now be validated.
What’s wrong with thyroid blood
tests?
The Lancet is one of the most prestigious scientific
journals in the world. It often reports new medical findings
that defy conventional wisdom. According to an article
published in the August 3, 2002 issue of The Lancet, the
problem with thyroid blood tests may be faulty “Reference
Ranges” that fail to reflect what the optimal level of
thyroid hormone should be in a particular individual.[10]
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Thyroid
Self Testing
Upon awakening before you get out of bed, put a
thermometer under your arm with no clothing between the
bulb and your armpit. Leave it there for 10 minutes (use
snooze alarm if you wake up to an alarm clock). Just
drowse for that time lying still. If the armpit method
is too inconvenient, you can put the thermometer in your
mouth for three minutes (or until the electronic
thermometer registers a temperature).
After the appropriate number of minutes take the
thermometer out and read it, writing down the result
right away. This is known as your Early AM Basal
Temperature, and the “normal” should be
between 97.8 and 98.2. The reading taken by armpit is
somewhat lower and somewhat more accurate than by mouth.
If you have a low-grade infection your temperature may
read higher than your “normal.” If it is
within the range mentioned above, you should repeat the
procedure every other day for two weeks. If you are a
menstruating female, do it on the 2nd and 3rd day of
your period.
If your average temperature over a two-week period is
lower than 97.8 to 98.2, you are probably hypothyroid.
If it is higher, then you are probably hyperthyroid (or
you have an infection somewhere).
|
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As stated earlier in this article, standard laboratory
reference ranges represent “average” populations,
rather than what the optimal range should be. Back in the
1960s, for instance, the upper reference range for cholesterol
extended to 300 (mg/dL). This number was based on a
statistical calculation indicating that it was
“normal” to have total cholesterol levels as high as
300. At that time, it was also “normal” for men to
suffer fatal heart attacks at relatively young ages. As
greater knowledge accumulated about the risk of heart attack
and high cholesterol, the upper limit reference range
gradually dropped to the point where it is now 200
(mg/dL).[11]
The same situation occurred with homocysteine reference
ranges. Up until recently, it was considered normal to have a
homocysteine blood reading as high as 15 (mm/L).[12] Most reference ranges now provide a
chart showing that homocysteine levels above 7 increase risk
of heart attack and stroke.[13]
It’s not just blood laboratory reference ranges that
fail to provide physicians and patients with optimal numbers.
For example, when your blood pressure is checked, a diastolic
number up to 90 (mm Hg) is considered normal. Yet a diastolic
blood pressure reading over 85 is associated with an increased
stroke risk. A high percentage of people over age 60 have
diastolic readings over 85 and this is the age group most
vulnerable to stroke.[14] So when
your doctor checks your blood pressure and says it’s
normal, your response should be that “normal” is not
good enough, since it is also normal for people over age 60 to
suffer a stroke. Instead, you should ask your doctor what is
the “optimal” range. In the case of diastolic blood
pressure, taking steps to keep it at 85 or below could greatly
reduce long-term vascular damage. It is important to note that
mid-life hypertension predisposes people to stroke later in
life, so keeping blood pressure readings in optimal ranges is
important at any age.
Scientists are now examining thyroid hormone reference
ranges and their findings indicate that it may be time to
change the way laboratories report TSH results.
The Thyroid Stimulating Hormone (TSH)
Test
The standard blood test used to determine thyroid gland
hormone output is the thyroid stimulating hormone test (TSH).
When there is a deficiency in thyroid hormone, the pituitary
gland releases more TSH to signal the thyroid gland to produce
more hormones.
When the TSH test is in “normal range,” doctors
usually assume that the thyroid is secreting enough thyroid
hormone. The question raised by The Lancet authors, however,
is whether today’s reference range for TSH reflects
optimal thyroid hormone status.
The TSH reference range used by many laboratories is
between 0.2 to 5.5 (mU/L). A greater TSH number is indicative
of a thyroid hormone deficiency. That is because the pituitary
is over-producing TSH based on lack of thyroid hormones in the
blood. Any reading over 5.5 alerts a doctor to a thyroid gland
problem and that thyroid hormone therapy may be warranted.
The trouble is that the TSH reference range is so broad
that most doctors will interpret a TSH reading as low as 0.2
to be as normal as a 5.5 reading. The difference between 0.2
and 5.5, however, is an astounding 27-fold. It would seem
almost absurd to think that a person could be in an optimal
state of thyroid health anywhere along this 27-fold parameter,
i.e. TSH readings between 0.2 and 5.5.
A review of published findings about TSH levels reveals
that readings over 2.0 may be indicative of adverse health
problems relating to insufficient thyroid hormone output. One
study showed that individuals with TSH values over 2.0 have an
increased risk of developing overt hypothyroid disease over
the next 20 years.15 Other studies show that TSH values over
1.9 indicate abnormal pathologies of the thyroid, specifically
autoimmune attacks on the thyroid gland itself that can result
in significant impairment.[15]
More ominous is a study showing that TSH values over 4.0
increase the prevalence of heart disease, after correction of
other known risk factors.[16]
Another study showed that administration of thyroid hormone
lowered cholesterol in patients with TSH ranges of 2.0 to 4.0,
but had no effect in lowering cholesterol in patients whose
TSH range was between 0.2 and 1.9.[17] This study indicates that in people
with elevated cholesterol, TSH values over 1.9 could indicate
that a thyroid deficiency is the culprit causing excess
production of cholesterol, whereas TSH levels below 2.0 would
indicate no deficiency in thyroid hormone status.
Doctors routinely prescribe cholesterol-lowering drugs to
patients without properly evaluating their thyroid status.
Based on the evidence presented to date, it might make sense
for doctors to first attempt to correct a thyroid deficiency
(based on a TSH value over 1.9) instead of first resorting to
cholesterol-lowering drugs.
In a study to evaluate psychological well being, impairment
was found in patients with thyroid abnormalities who were
none-the-less within “normal” TSH reference
ranges.[18]
Defying the reference ranges
The authors of The Lancet
study stated that, “the emerging epidemiological data
begin to suggest that TSH concentrations above 2.0 (mU/L) may
be associated with adverse effects.”
The authors prepared a chart based on previously published
studies that provide guidance when interpreting the results
from TSH blood tests. Here are three highlights from their
chart that may be useful in determining what your TSH values
really mean:
| TSH
greater than 2.0 |
Increased 20-year risk of
hypothyroidism and increased risk of thyroid
autoimmunity[15] |
|
| TSH greater than
4.0 |
Greater risk of heart disease[16] |
|
| TSH
between 2.0 and 4.0 |
Cholesterol levels decline in
response to thyroxine (T4) therapy[17] |
|
Despite presenting these intriguing findings, The Lancet authors stated that
more studies are needed to define optimal TSH level as between
0.2 and 2.0 instead of between 0.2 and 5.5. As a health
conscious person, however, this type of precise information
provides an opportunity to correct a medical condition that
has been unresponsive to mainstream therapies, or possibly
prevent disorders from developing in the first place.
This means if you suffer from depression, heart disease,
high cholesterol, chronic fatigue, poor mental performance or
any of the many other symptoms associated with thyroid
deficiency, you may want to ask your doctor to “defy the
reference ranges” and try thyroid replacement
therapies.
Measuring thyroid hormone levels
TSH is just one blood test that doctors use to assess
thyroid status. Other blood tests measure the actual amount of
thyroid hormone found in the blood.
The primary hormone secreted by the thyroid gland is called
thyroxine (T4). The T4 is then converted in the peripheral
tissues into metabolically active triiodothyronine (T3).
Doctors often test for TSH and T4 together, but this may
not accurately reflect thyroid deficiency in tissues
throughout the body. One study found that psychological well
being could be improved if T3 (like the drug Cytomel) is added
to T4 (like the drug Synthroid) therapy, while maintaining
thyroid function broadly within the standard reference
ranges.[19,20] What this means is
that even when TSH and T4 blood tests are within normal
ranges, a person can still be deficient in peripheral T3 and
benefit from Cytomel therapy.
Since T3 is the metabolically active form of thyroid
hormone, some doctors use it exclusively in lieu of T4 drugs
like Synthroid. The FDA’s recent notice to ban synthetic
T4 drugs like Synthroid because of inconsistent potencies
helps to validate the following statement made by Dr. Broda
Barnes more than 50 years ago:
| “Patients taking thyroid
replacement therapy have much better improvement of symptoms
with natural desiccated thyroid hormone rather than
synthetic thyroid hormones.” |
While the FDA has found many problems with T4 drugs, the T3
drug Cytomel has produced consistent clinical results and is
not a subject of the FDA’s proposed ban. Dr. Barnes
fought the drug companies over synthetic T4 drugs for years
and recommended desiccated thyroid (Armour) as the therapy of
choice for most patients.
An article in the New England
Journal of Medicine described a study in which patients
with hypothyroidism showed greater improvements in mood and
brain function if they received treatment with Armour thyroid
rather than Synthroid (thyroxine). The authors also detected
biochemical evidence that thyroid hormone action was greater
after treatment with Armour thyroid.[21]
It would appear that Dr. Broda Barnes has been
vindicated.
All hormone reference ranges may be
antiquated
It’s not just thyroid hormone deficiency that goes
unrecognized by so many physicians. Conventional medicine has
neglected virtually all the hormone imbalances that develop as
a part of growing older. The result is that aging people
suffer a variety of discomforts and lethal diseases that are
correctable and preventable if simple hormone adjustments are
made.
| Standard versus
Optimal |
| A person’s risk of contracting
lethal disease, suffering debilitating disorders and
prematurely aging can be partially predicted based on the
findings of blood tests that assess hormone levels. What
follows are the Standard Reference Ranges compared to the
Optimal Ranges for a 60-year old male: |
| Hormone |
Standard
Reference Range |
Optimal
Range |
| DHEA |
42-290 |
280-500 ug/dL |
| Insulin (fasting) |
6-27 |
Under 5 uU/mL |
| Free Testosterone |
6.6-18.1 |
15-22 pg/mL |
| Estradiol |
0-54 |
10-30 pg/mL |
| TSH |
0.2-5.5 |
Under 2.1 mU/L |
|
Aging men, for instance, often suffer from excess
production of insulin and estrogen, with simultaneous
deficiencies of free testosterone and DHEA. If a physician
were to test blood levels of all four of these hormones, the
standard “reference ranges” are so wide that most
men would fall into the so-called “normal”
category.
Standard reference ranges indicate that dangerously high
insulin and estrogen levels are “normal” in elderly
men. So are heart attacks, stroke, cancer, benign prostate
enlargement, weight gain, Type II diabetes, kidney impairment
and a host of other diseases that are associated with excess
insulin and estrogen.
 |
| Aging people who adjust their
hormone profiles to fit a more youthful profile can turn
back some of the effects that time has inflicted on their
bodies. In order to accomplish this, however, you must
defy the standard laboratory reference ranges and seek
the blood values of a much younger person. |
|
For instance, the standard reference ranges for free
testosterone and DHEA show that very low levels are perfectly
“normal” for aging men. It’s no coincidence
that these same aging men (with low testosterone/DHEA) suffer
high rates of depression, memory loss, atherosclerosis,
senility, impotency, high cholesterol, abdominal obesity,
fatigue and a host of other diseases related to low blood
levels of testosterone and DHEA.[22-34]
When it comes to assessing hormone status, standard
reference ranges have failed aging humans in a terrible way.
The reason is that reference ranges are adjusted to reflect a
person’s age. Since it is normal for an aging person to
have imbalances of critical hormones, standard laboratory
reference ranges are not flagging dangerously high levels of
estrogen and insulin or deficient levels of testosterone,
thyroid and DHEA. The box “Standard versus Optimal”
on this page shows standard hormone blood reference ranges for
men and compares them to what the “optimal” ranges
should be.
Most doctors still believe that imbalances of
life-sustaining hormones are “normal” for aging
people. These physicians think that nothing should be done to
restore hormone profiles to youthful ranges (and almost never
test hormone levels anyway).
The problem is that aging people no longer accept that they
should contract the diseases that happen to fit into their age
category. In other words, more 65-year olds are demanding the
health and vitality enjoyed by a younger person. This is not
possible if 65-year olds allow their hormone levels to
stagnate in today’s archaic reference ranges. If you are
80 years old and are told that your hormone profile is normal
for your age, tell your doctor that you would prefer the
hormone profile of a 25-year old since you perceive a 25-year
old as having more vitality and a reduced risk of contracting
lethal diseases than an 80-year old.
Optimizing your hormone levels
The Life Extension Foundation has published extensive
protocols relating to optimal male and female hormone
modulation. If you log on to www.lef.org , you can access the
following updated hormone-related protocols:
If you are a Foundation member and don’t have access
to a computer, call 1-800-544-4440 and we will print out and
mail these protocols to you at no charge.
Aging people who adjust their hormone profiles to fit a
more youthful profile can turn back some of the effects that
time has inflicted on their bodies. In order to accomplish
this, however, you must defy the standard laboratory reference
ranges and seek the blood values of a much younger person.
If your doctor won’t prescribe these critical blood
hormone tests, or if the retail cost is prohibitive, call
1-800-208-3444 to find out how you can obtain these tests by
mail order at prices below those charged by commercial
laboratories.
For longer life,
William Faloon
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