An article entitled " Why Heart Disease Mortality is low in France - the time lag explanation" by Malcolm Law and Professor Nicholas Wald at the Wolfson Institute of Preventative Medicine appeared in the British Medical Journal 1999:318:1471-1480 in May. It criticised the French Paradox theory and proposed a new explanation for the phenomenon.
The French Paradox is the observation that the French, who have
a high cholesterol diet with full cream sauces and pates for example,
and smoke, have much lower mortality from ischaemic heart disease
than other western countries with a similar diet and smoking habits.
The French Paradox was explained by Professor Serge Reynaud in
1991 as due largely to the higher consumption of wine (particularly
red wine) by the French when compared to other consumers.
Law and Wald argue that all alcohol has a cardio-protective effect
and that, furthermore, the French Paradox is due to three other
factors: Firstly, that the French medical profession do not document
all manifestations of ischaemic heart disease, such as heart failure
as due to coronary heart disease, but list them as "poorly specified
cardiac causes". Thus there is an under reporting of the incidence
of ischaemic heart disease in France, which the authors argue
explains about 12% of he difference between the cardiac mortality
rate between France and Great Britain.
Secondly, French women smoke at a third of the rate of British
women which significantly reduces the rate of ischaemic heart
disease in French women compared to British women because smoking
contributes greatly to the pathogenesis of ischaemic heart disease.
The third and last reason forms the crux of their argument; Law
and Wald argue that the basis for the bulk of the French Paradox
is that the differences in levels of heart disease reflects the
lower cholesterol diet that the French enjoyed thirty years ago
and not their current high fat diet. A lower cholesterol diet
is associated with much lower rates of ischaemic heart disease
and, according to Law and Wald, it is this time lag in cholesterol
consumption that explains why the French have lower incidence
of ischaemic heart disease. Eventually, when their current high
cholesterol diet takes effect, their incidence of heart disease
will rise and match rates in other Western countries.
Comparisons of consumption of selected food based on FAO food
balance shhets show that 35 years ago the French consumed more
meat than the British and had similar fat intakes. What is important,
which has been propounded by Serge Reynaud and Curtis Ellison,
is that French consumption of fruit, vegetables and vegetable
oils, as well as red wine of course (rather than the British consumption
of animal and dairy fats) is higher, which has lead to the incorporation
of the Mediterranean diet as part of the French Paradox.
To me the vascular disease protection afforded by wine is multifactorial;
First of all there is the "alcohol effect". Alcohol is the medically
active component of wine, and alcohol in any form favourably alters
the balance of fats in the blood, stimulating the liver to produce
'good' high density lipoproteins (HDL), which leaches out cholesterol
from the blood vessel walls, carrying it to the liver for excretion
via the bile.
Alcohol also helps inhibit clotting as it decreases platelet aggregation
or 'stickiness'. This effect lasts for 24-48 hours; hence for
alcohol to have a protective effect it must be drunk regularly
and moderately. Beer and spirits are usually consumed on an empty
stomach, whereas wine is consumed slowly by sipping over a meal.
Hence the wine is absorbed slowly, because it is consumed slowly
and the stomach emptying time is much slower when it is full of
There is the anti-oxidant benefit of reducing 'bad' low density
lipoproteins incorporation into blood vessel walls due to wine's
potent anti-oxidants such as resveratrol, quercitin and epicatechin
and it doesn't matter if the wine is red or white. There have
been many studies by Troup(1), Vinson and Hontz(2) and Jung (3)
for example which have shown that white wine is just as effective
as red wine as a cardio-protective agent. Dark ales, stouts and
aged whiskies also possess this anti-oxidant effect. Polyphenols
also protect, together with alcohol, against blood clotting, and
may relax blood vessel walls to allow better blood flow.
If Law and Wald's argument is that it is mainly the different
levels of cholesterol in diets that accounts for the paradox and
not the alcohol consumption, then it follows by their logic, that
the rate of coronary heart disease (CHD) in countries with a similar
British genetic stock and diet as Great Britain should have a
similarly high rate of CHD independent of alcohol consumption.
This we can prove is not so. Let us follow the CHD track record
of British descendents overseas, who have a similar genetic pool
and diet, as related to their drinking habits. Dr. Rodney Jackson
from the Department of Epidemiology at the University of Auckland,
New Zealand (4) has shown that alcohol consumption significantly
reduces CHD when comparing abstainers, moderate drinkers and heavy
drinkers in Auckland. Dr. Kevin Cullen's Busselton study (5) has
also shown that alcohol consumption significantly reduces rates
of CHD, particularly in British genetic pool and diet, and it
was the first research in the world to show this effect in women.
It is, however, Professor Leon Simon's Dubbo study (6) which really
shows the benefits of moderate alcohol consumption on a British
based population. In his study moderate drinkers, both men and
women, lowered their mortality rate by 51% (compared to Dr. Cullen's
one third improvement) when compared to non -drinkers. This shows
that the marked health benefit of moderate consumption of alcohol
is still valid on a British population.
To conclude, Dr. Law and Professor Wald concentrate heavily on
consumption of animal fats, and fail to mention the importance
of the Mediterranean diet as part of the French paradox. The Mediterranean
diet encourages the consumption of less meat and more fish, grains
and cereals, vegetables, fruit, olive oil and of course wine in
the every day diet if CHD is to be reduced. Secondly, the tables
illustrate that the French have enjoyed a high fat diet since
1965, i.e. for more than thirty years. If the researchers' theory
were correct, France would be showing an increase in rates of
CHD whereas in fact rates continue to fall.
Perhaps Curtis Ellison's comments sum up the debate;
"All in all, this paper presents some interesting topics for discussion
over a nice bottle of wine, but adds little to a serious scientific
inquiry into what factors are protecting the French from coronary
Dr. Philip Norrie is a general practitioner, vineyard owner and
a historian of wine and health. He is a member of the AIM editorial
References: (1) Troup.G et al. Free Radical Scavenging abilities
of beverages: International Journal of Food Science and Technology
1995, 30,P 535-537. (2) Vinson.J and Hontz B Phenols antioxidant
index: Comparative Antioxidant Effectiveness of red and white
wines. Advance American Chemical Society Abstracts January 15th
1995. (3) Jung.C et al Moderate red and wine consumption and the
risk of CHD. Herz/Kreisl 31 (1/99). (4) Jackson.R. et al Alcohol
Consumption and risk of coronary heart disease BMJ Vol 303 p??.
Cullen.K et al Alcohol and Mortality in the Busselton Study. International
Journal of Epidemiology ???. (6) Simons.L et al Alcohol intake
and survival in the elderly: a 77 month follow up in the Dubbo
study. AUST NZJ Med.1996,26 p 662