From these studies it is estimated that half of the beneficial
effects of moderate alcohol intake is due to increased high density
lipoprotein cholesterol concentrations. This calculation may,
however, be an underestimate because it does not take into account
measurement error in the assessment of average alcohol intake
or biological variability in HDL-lipoprotein cholesterol concentrations.
Also potential confounding by other lifestyle factors such as
diet, obesity and physical activity were usually not considered.
Furthermore other biochemical variables such as fibrinogen, tryglycerides
and insulin were not measured in these simultaneous models claim
Rimm et al.
The study by Eric Rimm et Al, published in the BMJ (Volume 319,11th Dec 99) sought to clarify the perceived short comings of the above studies
by reviewing 42 experimental studies of alcohol, which provided 67
separate data records.
Rimm et al's study found that an experimental dose of 30g of ethanol
a day increased concentrations of high density lipoproteins (HDL)
by 3.99mg/dl, apolipoprotein A1 by 8.82mg/dl and triglyceride
On the basis of published associations between these biomarkers
and the risk of coronary heart disease 30g of ethanol a day would
cause an estimated reduction of 24.7% in risk of coronary heart
disease. The authors conclude;
'Results from our quantitative review suggest that moderate intake
is causally related to lower risk of coronary heart disease through
alcohol induced changes in lipids and haemostatic factors'.