Beer : Health and Nutrition

The Impact of Alcohol on Health 125
come through the diet. The quantity of cholesterol produced is increased in proportion
to the level of saturated fatty acids in the diet (polyunsaturated fatty acids reduce
blood cholesterol), and also the trans saturated fatty acids, i.e. those that are produced
industrially by catalytic hydrogenation (Krisetherton 1995). High sugar intake can lead
to high formation of saturated fats in the body. Indeed, any imbalance in metabolism
such that there is an excess of calories over those needed to sustain the body will lead
to an accumulation of fat. Obesity, hypertension, diabetes, sedentary living and the use
of cigarettes all increase the risk of atherosclerosis.
As cholesterol and other lipids such as the triglycerides are insoluble in aqueous
systems, they are transported through the body by combination with proteins, as lipoproteins.
The principal carrier of cholesterol is low-density lipoprotein (LDL) and there
is a strong positive correlation between its level and the risk of atherosclerosis. Hence
LDL is frequently referred to as ‘bad cholesterol’.
A lower percentage (20–30%) of the blood cholesterol is in the form of high-density
lipoprotein (HDL), which is responsible for transporting cholesterol away from the arteries
to the liver where it is metabolised. This role has caused HDL to be named ‘good
cholesterol’, such that high levels of HDL appear to afford protection against heart attack.
Thus there is an inverse correlation between levels of HDL and atherosclerosis.
There is now a plethora of papers arguing that moderate consumption of alcohol
counters coronary heart disease [see, for example, Dyer et al. 1977; Hennekens et al.
1978; Ramsey 1979; Marmot et al. 1981; Gordon & Kannel 1983 (the Framingham
study); Kozarevic et al. 1983; Yano et al. 1984; Moore & Pearson 1986; Klatsky et al.
1992; Maclure 1993; Verschuren 1993]. Alcohol causes a lowering of LDL cholesterol
in the plasma and an increased level of HDL cholesterol (HDL 2 and HDL 3 ) and apolipoproteins
A-I and A-II (Clevidence et al. 1995; Goldberg et al. 1995; Jansen et al.
1995; Parker et al. 1996).
Alcohol also appears to lower the risk of blood clotting by reducing the level of
brinogen in blood plasma (Stefanick et al. 1995) and lessening the tendency of blood
platelets to aggregate (Renaud et al. 1992). The bene ts apply to both men and women
(Nanchahal et al. 2000).
Doyens of the eld have included Arthur Klatsky in Oakland, California, Norman
Kaplan of the University of Texas Southwestern Medical Center, and Sir Richard Doll
in Oxford, England.
The phenomenon has taken the name the ‘French paradox’, on account of the unexpectedly
low risk of cardiovascular disease in a country noted for its intake of very fatty
foods. We can look back nearly two centuries to the rst noting of this effect, when
an Irish doctor, Samuel Black, remarked on the much greater incidence of angina in
France as opposed to Ireland, which he believed was ascribable to ‘the French habits
and modes of living, coinciding with the benignity of their climate and the peculiarity
of their moral affections’ (Black 1819). The occurrence is now sometimes called