People with high cholesterol live the
longest.
This statement seems so incredible that
it takes a long time to clear one´s mind to fully understand its
importance. Yet, the fact that people with high cholesterol live the
longest emerges clearly from many scientific papers. But let us take
a look at heart mortality, the risk of dying from a heart attack if
cholesterol is high.
Consider the finding by Dr. Harlan
Krumholz of the Department of Cardiovascular Medicine at Yale
University, who reported that old people with low cholesterol died
twice as often from a heart attack as did old people with high
cholesterol. Supporters of the cholesterol campaign consistently
ignore his observation, or consider it as a rare exception, the
result of chance among a huge number of studies finding the opposite.
But it is not an exception; there are
now a large number of findings that contradict the lipid hypothesis.
To be more specific, almost all studies of old people have shown that
high cholesterol is not a risk fact for coronary heart disease. This
was the result of a search in the Medline database for studies
addressing that question. Eleven studies of old people came up with
that result, and a further seven found that high cholesterol did not
predict all-cause mortality either, and more such studies have been
published since then.
It has been mentioned before, but it is
worth repeating, that more than 90 percent of those who die from a
heart attack or a stroke have passed the age of 65. You may also
recall that high cholesterol is not a risk factor for women, or for a
number of other population groups.
But there is more comfort for those who
have high cholesterol. At least fifteen studies found that total
mortality was inversely associated with either total or
LDL-cholesterol, or both. This means that it is actually much better
to have high than to have low cholesterol if you want to live to be
very old.
Many studies have found that low
cholesterol in certain respects is worse than high cholesterol. For
instance, in nineteen large studies of more than 68,000 deaths,
reviewed by David R. Jacobs and his co-workers from the Division of
Epidemiology at the University of Minnesota, low cholesterol
predicted an increased risk of dying from gastrointestinal and
respiratory diseases. Most gastrointestinal and respiratory diseases
have an infectious origin. Therefore, a relevant question is whether
it is the infection that lowers cholesterol or the low cholesterol
that predisposes to infection. You have probably already guessed
what the directors of the cholesterol campaign have said, but is it
true?
To answer that question David Jacobs´
group followed more than 100,000 healthy individuals in the San
Francisco area for fifteen years. At the end of the study, those who
had low cholesterol at the start of the study had been admitted more
often to hospital because of an infectious disease of the respiratory
system or because of another type of infection. This finding cannot
be explained away with the argument that the infection had caused
cholesterol to go down, because how could low cholesterol, recorded
when these people had no evidence of infection, be caused by a
disease they had not yet encountered? Isn´t it much more likely
that low cholesterol in some way made them more vulnerable to
infection, or that high cholesterol protected those who did not
become infected. Much evidence exists to support that
interpretation.
Heart disease may lead to a weakening
of the heart muscle. A weak heart means that less blood and
therefore less oxygen is delivered to the arteries. To compensate
for the decreased power, the heart beat goes up, but in severe heart
failure, this is not sufficient. Such patients become short of
breath because too little oxygen is delivered to the tissues, the
pressure in their veins increases because the heart cannot deliver
the blood away from the heart with sufficient power, and they become
edematous, meaning that fluid accumulates in the legs and in serious
cases also in the lungs and other parts of the body. This condition
is called congestive or chronic heart failure.
There are many indications that
bacteria or other microorganisms play an important role in chronic
heart failure, and also that the risk of heart failure is much
greater in people with low cholesterol.
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