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After
testing the Bone Mineral Density (BMD) of over 10,000 men and women, taking their histories and considering
their risk factors, I concluded that the t-scale used by the medical community and
World Health Organization (WHO) is flawed.
The reason can be found in my analysis of what determines “normal”
according to this "t-score" system.
The
t-score is a system that ranks the difference between your bone mineral density,
and the median bone mineral density of a young, healthy, normal (YHN)
population, aged 30-35. This is the age bone mass is at it’s naturally
highest level, or peak bone mass. For greater
accuracy, this median figure is ethnicity and gender matched so you
are compared to YHN people more like yourself.
The narrower the population the better.
For instance, what 40 year old Asian female would want be compared to a
median (population) that includes african-american women, who have naturally denser bones?
The
flaw in this system, becomes evident when you understand what “median”
really means. This is not
necessarily a high BMD score, it
simply represents where most people in the study group or population
happen to score.
The median BMD is assigned the t-score of zero, and your own BMD is reported in
Standard Deviations (SD) above or below that median. According to the
WHO;
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t-scores
above +1 SD are considered “High BMD”.
-
t-scores
between +1SD and –1 SD are
considered “Normal"
-
t-scores
between –1SD and –2.5SD are considered “Osteopenic.”
-
t-scores of –2.5SD or less are considered “Osteoporotic.”
So if the population being studied
has poor bone density, then the median (a t-score
of zero) represents a poor quality bone. According to the current scoring
method, as long as you score
within one standard deviation (SD) from that median (zero), you are called “normal”.
Again, I find this misleading because if a person scores a -0.9 SD or even a
-1.0SD, he or she is told they have "normal" bones. Meanwhile, they may
actually be just months away from a condition called osteopenia. And that’s a
"normal" healthy person!
Here
is another way to look at it. Another common median
value is I.Q.
I.Q. is an
intelligence quotient used to determine the relative intelligence of a person.
So it’s a measure of how intelligent you are compared to the median
intelligence of a population. The
median IQ is 100. I’m almost
afraid to ask what segments of the population are included in the statistics,
but anyway, an IQ of 100 does not make that person real smart does it?
Now, the further away from 100 you get, the more or less intelligence you
have, and the fewer people there are at that level.
Just like there are not as many people with an I.Q. of 140, not many
people have bones that are +4 SD above the median BMD.
I often joke with clients who have very high BMD, “if this were an
I.Q. test, you’d be a genius…too bad it’s not!”
While
people with bone density scores within one standard deviation (normal t-scores)
are not now at increased risk for fracture, I suggest looking at the t-score along with
expected loss curves for your particular ethnicity and gender group.
In this way we can predict approximately when you may reach a state of
osteopenia or osteoporosis. The
highly predictive nature of an accurate BMD test, when plotted on the expected loss
curve, is a valuable tool for motivating people to take preventative
action.
"Reversing Osteoporosis Handbook" by Reed Davis. Only
$14.95
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