In the thread re: curing disease in a message which seems to have

I keep hearing these stories about the dangers of low cholesterol
levels but have seen no references quoted concerning the source
material for these comments. Can you quote the sources of this
evidence ?  

Also how are these "low cholesterol levels" defined ?

Current "desirable levels" in New Zealand ( for people who do not
already have Coronary Heart Disease ) seem to be:

                             mmol/L         mg/dL

Total Cholesterol            < 5.2         < 201
HDL                          > 1.0         >  39
** LDL                     1.7 to 4.5     66 to 174
Triglycerides                < 1.5           131

Risk Ratio: Total Cholesterol/HDL   < 4.5

( NOTE:
    ** LDL levels quoted above are the normal range of values for
    LDL found in NZ testing laboratories. I have not seen a
    "desirable level" quoted for LDL by New Zealand authorities.
    I do not know why.)  

The trend is that these levels are constantly being revised
downwards. It is therefore important to examine the evidence for the
undesirable effects of reducing cholesterol to low levels - and
again it is necessary to numerically define what exactly "low
levels" are.  

As for anecdotal evidence - some of the healthiest people I know
have Total Cholesterol values of 4.5 mmol/L ( 174 mg/dL ) or lower.
Also there have been studies of populations with very low Total
Cholesterol levels eg Japanese and Eskimos ( I think ).

Bye,

Recently in Europe, there have been new guidelines published by the European
Atherosclerosis Society: these guidelines use the patient's risk in addition to
their cholesterol.

If there are no risk factors, the total cholesterol level should be not greater
than 5.2 but only dietary measures are indicated unless cholesterol is greater
than 7.8.  As the number of risk factors (smoking, hypertension, ischaemic  
heart disease etc.) increases, the need to reduce cholesterol to less than 5.2
increases.

--
Dr. Tim Reynolds                 | Interests: Medical computing

Consultant Chemical Pathologist, | Essential fatty acids and calcium metabolism
Burton Hospital.                 | Renal stones

: > Current "desirable levels" in New Zealand ( for people who do not
: > already have Coronary Heart Disease ) seem to be:
: >
: >
: >                              mmol/L         mg/dL
: >
: >
: > Total Cholesterol            < 5.2         < 201
: > HDL                          > 1.0         >  39
: > ** LDL                     1.7 to 4.5     66 to 174
: > Triglycerides                < 1.5           131
: >
: > Risk Ratio: Total Cholesterol/HDL   < 4.5
: >
: > The trend is that these levels are constantly being revised
: > downwards. It is therefore important to examine the evidence for the
: > undesirable effects of reducing cholesterol to low levels - and
: > again it is necessary to numerically define what exactly "low
: > levels" are.  
: >

: Recently in Europe, there have been new guidelines published by the European
: Atherosclerosis Society: these guidelines use the patient's risk in addition : to their cholesterol.

: If there are no risk factors, the total cholesterol level should be not : : :greater than 5.2 but only dietary measures are indicated unless cholesterol :is greater than 7.8.  As the number of risk factors (smoking, hypertension, :ischaemic heart disease etc.) increases, the need to reduce cholesterol to :less than 5.2 increases.

The figures I quoted were mainly those issued by the Lipid Research
Groups of the Christchurch and Otago Schools of Medicine. The NZ
National Heart Foundation would probably not substantially differ
from those values. I am not sure that we have a NZ Atherosclerosis
Society.  

The leaders in NZ medical circles, concerning cholesterol, tend to
be the Hospital Cardiologists and the Lipids Research Groups of the
Medical Schools. The GPs are better informed than they were and
their knowledge and awareness seems to be increasing fairly rapidly.
At one time regular {*filter*} Pressure tests were considered a
reasonable measure of the risk of heart problems. Lipids profile
tests are now far more common than they were.

What your figures for Europe probably show is the quite considerable
variation in thinking on lipid levels throughout the world. Also
Europe is a large place with many diverse populations, diets and
lifestyles.

However, your figure of 7.8 for Total Cholesterol would seem high in
view of the fact that I have been told ( on excellent authority )
that even strict diet adherence will at best only achieve a 10%
reduction in TC level. So 7.8 could reduce to 7.0 at best.

Sole use of TC values as guidelines also ignores the importance of the
total lipids profile ( TC; HDL; LDL and Triglyceride levels ).
Dr Kenneth Cooper of the USA, in his 1988 book "Controlling Cholesterol"
devotes an entire chapter to "The Great Principle of Balance" in
relation to cholesterol (lipids) profiles.

Quite a bit has also been said about the use of exercise to increase
the desirable HDL levels but I cannot recall seeing any controlled
study results showing what can be achieved in HDL increases. The
statements that HDL increase with exercise are not usually
accompanied by any percentage values. Perhaps I have missed seeing
this evidence ?  

And in the final analysis it is still all a matter of opinions :-)

Bye,

The best response to diet in a pure hypercholesterolaemia was a reduction from
10.0 mmol/L to 4.5 mmol/L (the patient lost 56 pounds and cut out chocolate (a
great hardship)) and in a mixed hyperlipidaemia from trig 62.5 mmol/L ,
Cholesterol 15 mmol/L to trig 2mmol/L, cholesterol 5.8 mmol/L (the patient
had a diet that consisted almost entirely of bacon fat with no vegetables (her
husband had all of the meat), we taught her to eat properly and she was cured)).

Otherwise I think I'd agree that on average the change due to diet is usually
small (no greater than 1.5 mmol/L change).
--
Dr. Tim Reynolds                 | Interests: Medical computing

Consultant Chemical Pathologist, | Essential fatty acids and calcium metabolism
Burton Hospital.                 | Renal stones