QPMPA Journal September 2011 - Qualified Private Medical ...

medical science
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demystifying the
cholesterol myth
Low blood cholesterol
and cancer
So far, advertisers and news media have
concentrated on the supposed danger
from high levels of blood cholesterol. The
dangers of low blood cholesterol levels
have largely been ignored. Countries with
diets high in saturated fats also tend to
have high levels of colon cancer. In 1974
a review of the Framingham data and
those from Keys’ ‘Seven Countries’ study
was carried out. It was expected to show
that the cancer could also be blamed on
high blood cholesterol. However, the baffled
researchers found the opposite: those
with the cancer had cholesterol levels that
were lower than average.
Reports of more than twenty studies into
the relation between blood cholesterol
and cancer have been published since
1972. Most have reported an association
between low blood cholesterol and cancer.
The authors of the Renfrew and Paisley
Study conclude:
“It may be a mistake to assume that
dietary advice given to the general
The wisdom of the body decides the level of cholesterol and liver
produce it as required. To kill a few rats, should we burn a house!
Prof. B. M. Hegde
Nature has taken good care that theory should have little effect on practice.
– Samuel Johnson
population to reduce the intake of saturated
fat will necessarily reduce overall
mortality.”
In a study from the USA published in
1990, changes in blood cholesterol over
time were studied in patients with colon
cancer. The doctors found that there had
been an average thirteen percent decline
in blood cholesterol levels in the ten years
prior to diagnosis of the cancer compared
with an average increase of two percent
in the control group. Both those with
the cancer and those free from it had similar
blood cholesterol levels initially.
It is possible that the decline in blood
cholesterol levels was a result of the cancer,
not the cause of it, but the investigators
rule this out. They compare cholesterol
studies with apparently contrary
findings and show that in reality they
are consistent. Comparing those that
reported normal or high cholesterol
readings several years prior to diagnosis
with others where, at the time of diagnosis,
levels were low, they conclude that
it was a long term lowering of blood
cholesterol levels that gave rise to the
cancers. Interestingly, the average blood
cholesterol level of those who developed
the cancers declined to an average 5.56
mmol/l and yet the British government’s
Health of the Nation strategy still aims
to reduce everyone’s levels to below
5.2 mmol/l.
Low cholesterol means
more strokes
Published at about the same time was a
very large study in Japan, covering two
decades, which concluded that low levels
of blood cholesterol also increase the
incidence of stroke. Over the past few
decades, Japan has experienced a rapid
change in its living and eating patterns.
The Japanese are eating more total fat,
saturated fatty acids and cholesterol,
animal fats and protein, and less rice
and vegetables. This has provided a
unique opportunity for a large-scale,
natural experiment into the effects of
those changes.
Investigators have shown that this
change to Western and urban eating patterns,
departing as it does from centuries
old traditions, has been accompanied by
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134
QPMPA.JMS . Vol. XXV . No. 3 . June-Sept. 2011