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Antiquated
Hormone “Reference
Ranges”
Conventional
medicine tends to neglect the hormone imbalances that develop in
both men and women as 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.
Aging men, for instance, often suffer from excess production
of insulin and estrogen, with simultaneous deficiencies of free
testosterone and dehydroepiandrosterone (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 (but
so are heart attack, 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).
The standard reference ranges for free testosterone and DHEA
show that very low levels are perfectly “normal” for
aging men. It is no coincidence that these same aging men (with
low levels of testosterone/DHEA) have 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.4-15
Another example of flawed reference ranges can be seen in a blood
test used to assess thyroid status known as the thyroid stimulating
hormone (TSH) test. The TSH reference range used by many laboratories
is 0.2-5.5 mU/L. A greater TSH level is indicative of a thyroid
hormone deficiency. That is because the pituitary gland is over-signaling
TSH due to low levels of thyroid hormone 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 27-fold, a parameter far too great to indicate optimal or even
normal thyroid function.
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.16 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.17
A more startling study showed that TSH values over 4.0 increase
the prevalence of heart disease, after correcting other known risk
factors.17 Another study showed that administration of thyroid
hormone lowered cholesterol in patients with TSH ranges of 2.0-4.0
but had no effect in lowering cholesterol in patients whose TSH
range was 0.2-1.9.18 It also showed 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 a normal 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 resorting to cholesterol-lowering drugs.
In a study done to evaluate psychological well being, impairment
was found in patients with thyroid abnormalities who were nonetheless
within “normal” TSH reference ranges.19 The authors
of a study published in the August 3, 2002, issue of The Lancet
stated that “the emerging epidemiological
data begin to suggest that TSH concentrations above 2.0 (mU/L)
may be associated with adverse effects.”
When it comes to assessing hormone status, the use of standard
reference ranges has failed aging people because 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 table above shows standard hormone blood reference
ranges for men (age 60) and compares them to what the “optimal” ranges
should be.
Defying the Reference Ranges
Traditional medical thinking accepts
that imbalances of life-sustaining hormones are “normal” in
aging people. Traditional practitioners almost never test hormone
levels because they think that nothing should be done to restore
hormone profiles to youthful ranges. More and more, however, aging
people are seeking the health and vitality of a younger person.
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 because you perceive a 25-year-old
as having more vitality and a reduced risk of contracting lethal
diseases.
The Most Important Blood Tests
The Life Extension Foundation suggests
that a basic battery of tests be performed annually. The recommended “Male
Panel” consists
of a complete blood count (CBC)/chemistry test, homocysteine, total
and free testosterone, estradiol, prostate-specific antigen (PSA),
and DHEA. The recommended “Female Panel” consists of
the complete CBC/chemistry test, estradiol, progesterone, total
and free testosterone, DHEA, and homocysteine.
If a serious abnormality is detected—such as elevated homocysteine,
hormone imbalance, high PSA—testing should be repeated more
often to determine the benefits of whatever therapy you are using
to correct the potentially life-shortening abnormality.
We also recommend that you consult with your physician regarding
any other test that may be appropriate for your individual condition.
The remainder of this article provides detailed information about
individual tests and ranges that can be used to assess your health
and longevity. At the end of this article, we provide information
about the new lower-cost blood testing available to Life Extension
members.
Male and Female Testing Panels
The Male and Female Testing Panels
are a terrific place to begin to proactively take charge of your
health.
These panels comprise the most requested tests, which also happen
to be the best and most comprehensive screening tests capable of
identifying many common and not-so-common conditions, identifying
risk factors for future disease, and offering a clinical snapshot
of your current physiologic well being.
Both panels consist of a full chemistry and complete blood count
(CBC) measuring 35 different blood components, which assess cholesterol
and triglyceride levels, blood glucose, iron and mineral levels,
kidney and liver function, and blood cell components.
The male and female panels also test for levels of total and
free testosterone, DHEA-S (an indicator of adrenal cortical function),
estradiol, homocysteine, and C-reactive protein. Both homocysteine
and C-reactive protein, along with levels of cholesterol lipoproteins,
are powerful predictors of cardiovascular disease.
The male panel also includes the PSA (prostate-specific antigen)
test, which is a very sensitive marker for prostate cancer. The
female panel includes a test for progesterone levels, providing
information concerning female fertility, ovulation cycles, and
possible hormonal tumors.
Following are snapshots of the various tests offered in the male
and female test panels.
Chemistry and complete blood count (CBC) PANEL
The chemistry panel
provides a wide range of information to assess cardiovascular,
endocrine (glucose levels), hepatobiliary, and kidney function.
The CBC panel provides information on the presence of infectious
organisms, anemias, nutritional deficiencies, lymphoproliferative
disorders (i.e., leukemia), and other hematological disorders.
Cardiovascular
Chemistry cardiovascular system tests include total
cholesterol, HDL- and LDL-cholesterol, triglycerides, and the ratio
between total cholesterol and HDL levels, which is more valuable
as a predictor of heart disease than total cholesterol or HDL levels
alone. When assessed along with C-reactive protein and homocysteine
blood levels, the information attained offers a very powerful indicator
of cardiovascular status, including risk of future heart disease.
Endocrine
The chemistry panel also looks at fasting glucose levels
in the plasma. Skewed values may indicate problems with glucose
metabolism, such as hyperglycemia (diabetes mellitus) or hypoglycemia
(low blood sugar, which may preempt hyperglycemia in some individuals),
acidosis or ketoacidosis, and further problems with carbohydrate
metabolism.
Hepatobiliary
Abnormal levels of protein/albumin/globulin, albumin/globulin ratio,
bilirubin, alkaline phosphatase, lactic dehydrogenase (LDH), AST
(SGOT), ALT (SGPT), iron, cholesterol, and cholesterol lipoproteins
are indications of potential liver/biliary problems. These may
include liver damage induced by alcohol or drug use, liver cancer,
or obstruction of the bile duct, among others. Together, ALT and
AST allow for differential diagnosis of disorders associated with
the hepatobiliary system and the pancreas. High levels of alkaline
phosphatase may also indicate abnormally high levels of vitamin
D.
Kidney
Kidney function may be assessed by evaluating blood levels
of the following: blood urea nitrogen (BUN), uric acid, creatinine,
BUN/creatinine ratio, sodium, potassium, and chloride ions. BUN
measures the amount of urea nitrogen (a breakdown product of protein
metabolism) in the blood. Most diseases involving the renal system
affect urea excretion by the kidneys and will elevate BUN levels.
Creatinine, a breakdown product of creatine metabolism (creatine
is an important constituent of muscle), is excreted by the kidneys—abnormal
levels may indicate renal failure or dehydration (elevated levels)
or myasthenia gravis or late-stage muscular dystrophy (decreased
levels). The ratio between BUN and creatinine may help determine
the reason behind decreased kidney function (such as dehydration).
Sodium, potassium, and chloride ion levels assist in the evaluation
of hydration status and electrolyte balance. Low levels of potassium
may indicate acute renal failure.
Hematological
abnormalities and infection
Complete blood counts include red blood
cells (RBCs) and white blood cells (WBCs) and their components:
hematocrit, hemoglobin levels, and platelet counts.
RBC, hematocrit, and hemoglobin
Abnormally low RBC levels may indicate
iron, folate, and vitamin B6 and B12 deficiencies. Low hemoglobin
or hematocrit levels may indicate anemia; high hematocrit values
may suggest dehydration. Abnormal distribution of the RBC width
(RDW) compared with the mean corpuscular hemoglobin volume (hematocrit
divided by RBC count) may detect such problems as aplastic anemia,
thalassemia, anemias, and deficiencies of iron, folate, and vitamin
B12.
Platelets
Platelets are an essential part of the coagulation (clotting)
cascade and normal levels are necessary to maintain hemostasis.
Decreased platelet counts may be seen in patients undergoing chemotherapy,
and in hemolytic anemia, leukemia, and other disorders that diminish
clotting ability.
WBCs and their components (lymphocytes,
monocytes, neutrophils, eosinophils, and basophils)
Increased levels of all types of WBCs
in the blood are usually associated with bacterial, viral, parasitic,
or protozoal infections. Neutrophils, which are the first WBCs
to respond to infection, often indicate infection or emotional
stress (increased levels) or chronic infection, bone marrow depression,
or iron, folic acid, or vitamin B12 and B6 anemias (decreased levels).
Differential assessment of the CD4/CD8 T-lymphocyte ratio (a separate
test) may confer important information concerning immune status,
especially in patients who are immune-suppressed (i.e., HIV/ AIDS).
The presence of eosinophils in the blood is a good indication of
parasitic or fungal infection, or a response to allergy. The number
of monocytes in the blood is often increased (very high levels)
in patients with leukemias and Hodgkin’s or non-Hodgkin’s
lymphoma.
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