A Hearty Buzz from Alcohol
By Marjet Heitzer, Ph.D.
The Plateau-proof Diet Foundation
http://www.plateauproodiet.com
In recent years, moderate consumption of alcohol, particularly
red wine, has been associated with various health benefits
including lowering the risk of coronary heart disease (CHD,
atherosclerosis), ischemic stroke (interrupted blood flow to the
brain due to a blood clot or bursting of a blood vessel) and
cerebral thrombosis (blood clot in the brain). For example,
light to moderate drinkers have less risk of developing CHD than
abstainers (1). However, heavy drinking actually raises a
person's risk of developing CHD. This article will examine
scientific evidence associated with alcohol consumption and CHD.
However, this article is by no means promoting increased alcohol
consumption in order to attain cardioprotection. Alcoholism is
associated with many more health problems such as liver
cirrhosis, cancer, neurological diseases as well as heart
complications like alcoholic cardiomyopathy (weakening of the
heart muscle seen in some chronic alcoholics) and high blood
pressure. Individuals should discuss alcohol consumption with
their physician.
Part of the epidemiological evidence associated with the
benefits of alcohol consumption, particularly red wine, comes
from the French Paradox (2). Despite the high amounts of
saturated fat in their diet, the French have a relatively low
incidence of CHD. Comparing the eating and drinking habits of
European countries that have low rates of CHD resulted in a
common factor: consumption of more red wine as compared to other
countries. This led to the question: Could red wine consumption
lead to heart health benefits?
In the Copenhagen City Heart Study, 13,285 men and women were
observed for twelve years (3). Individuals, who drank wine, had
50% less CHD. In this study, beer and spirit drinkers had no
reduction in CHD. However, another similar study indicated that
moderate beer consumption decreased the risk of CHD by 22% (4).
So what is CHD? Atherosclerosis is the accumulation of fatty
plaques in blood vessels, leading to decreased blood flow to the
heart (See Above Figure). One of the initial steps in the
progression of atherosclerosis is the inability of the blood
vessels to relax or vasodilate. Smoking, hypertension (high
blood pressure), high cholesterol, and diabetes are just a few
complications that may be responsible for reduced vasodilation.
Proliferation and migration of smooth muscle cells underneath
the endothelium (cells lining the blood vessels) results in
decreased blood vessel relaxation and a thickening of the blood
vessel wall. In the end, the plaque ruptures and leads to either
a heart attack or stroke.
In laboratory studies, alcohol improves endothelial cell
function and inhibits vascular smooth muscle cell proliferation
and migration, resulting in more relaxed blood vessels (5).
Furthermore, red wine reduced the production of endothelin-1, a
protein involved in blood vessel vasoconstriction (6). Finally,
alcohol consumption leads to decreased LDL (bad cholesterol)
oxidation, increased HDL (good cholesterol) concentrations, and
decreased platelet aggregation, resulting in a better blood
lipid profile and less plaque formation (5). Taken together,
alcohol itself improves vascular function, resulting in reduced
risk of developing CHD.
So, why does wine especially red wine have additional health
benefits as opposed to beer or spirits? Studies using
dealcolized red wine showed that some of the cardioprotective
characteristics of red wine are independent of the alcohol.
Along with alcohol, red and white wine is composed of many other
chemicals from the grape, including polyphenols that act as
antioxidants. However, red wine typically has more antioxidant
polyphenols than white wine. Plant polyphenols are responsible
for the color of the grape. Red wine has a variety of
polyphenols including resveratrol (stilbene) and flavinoids. The
antioxidant function of red wine flavinoids decreases LDL (bad
cholesterol) oxidation (7). Because oxidized LDL reduces blood
vessel relaxation, it is a crucial step leading to heart
disease. Along with reducing oxidized LDL concentrations,
polyphenols may also reduce cholesterol absorption the gut,
leading to decreased serum cholesterol concentrations. Finally,
grape polyphenols decrease plasma triglyceride concentrations by
39% (8). All of these changes may result in suppression of
atherosclerosis, thus reduced risk of developing CHD.
What is moderate and heavy consumption of alcohol? Moderate
consumption of alcoholic beverages (1-2 drinks/day) 3 to 4 days
per week results in a 30% reduction in risk of developing CHD
and a 20% reduction in the risk of developing ischemic stroke.
Each drink consists of 1.5 ounces of liquor, 5 ounces of wine,
or 12 ounces of beer. However, heavy drinking as well as binge
or weekend drinking (5+ drinks for women and 9+ drinks for men)
are not associated with any cardioprotective effects. In fact,
heavy and binge drinkers had a higher risk of developing CHD as
compared to abstainers.
Do only healthy individuals benefit from moderate alcohol
consumption? Healthy individuals along with patients with a
history of heart attack or diabetes all may benefit from
moderate drinking. Men with a history of ischemic heart disease
had an increase in blood vessel size after ingestion of both red
and white wine (9). Furthermore, in a model of insulin
resistance, insulin resistant rats benefited from the
consumption of alcohol, red wine polyphenols, or both (10). In
this model of insulin resistance, rats are fed a high fructose
diet that leads to metabolic syndrome followed by glucose
intolerance, visceral obesity, hypertension, insulin resistance,
and dyslipidemia. Drinking alcohol or red wine polyphenols led
to increased insulin sensitivity, in turn resulting in lower
blood glucose and normal blood pressure. Rats that consumed
alcohol alone had decreased insulin resistance.
This article addresses the heart healthy benefits of moderate
alcohol consumption. Alcohol consumption only for the purpose of
cardioprotection is not advised, and people who abstain from
drinking alcohol should not start drinking alcohol for the
health benefits. Furthermore, increased consumption of alcoholic
beverages does not lead to increased protection. In fact, as
previously mentioned, heavy or binge drinking leads to increased
risk of developing CHD.
The Plateau-Proof Diet (http://www.plateauproofdiet.com)
considers the caloric contribution of beverages as well as
foods. As with anything you consume while participating in The
Plateau-Proof Diet (http://www.plateauproofdiet.com), consult
the CP and FP tables before consumption of any beverage
containing alcohol or not.
1. Rehm J, Sempos CT, Trevisan M 2003 Alcohol and
cardiovascular disease--more than one paradox to consider.
Average volume of alcohol consumption, patterns of drinking and
risk of coronary heart disease--a review. J Cardiovasc Risk
10:15-20
2. Renaud S, de Lorgeril M 1992 Wine, alcohol, platelets, and
the French paradox for coronary heart disease. Lancet 339:1523-6
3. Schnohr P, Jensen JS, Scharling H, Nordestgaard BG 2002
Coronary heart disease risk factors ranked by importance for the
individual and community. A 21 year follow-up of 12 000 men and
women from The Copenhagen City Heart Study. Eur Heart J 23:620-6
4. Szmitko PE, Verma S 2005 Cardiology patient pages. Red wine
and your heart. Circulation 111:e10-1
5. Augustin LS, Gallus S, Tavani A, Bosetti C, Negri E, La
Vecchia C 2004 Alcohol consumption and acute myocardial
infarction: a benefit of alcohol consumed with meals?
Epidemiology 15:767-9
6. Corder R, Douthwaite JA, Lees DM, et al. 2001 Endothelin-1
synthesis reduced by red wine. Nature 414:863-4
7. Deckert V, Desrumaux C, Athias A, et al. 2002 Prevention of
LDL alpha-tocopherol consumption, cholesterol oxidation, and
vascular endothelium dysfunction by polyphenolic compounds from
red wine. Atherosclerosis 165:41-50
8. Zern TL, Fernandez ML 2005 Cardioprotective effects of
dietary polyphenols. J Nutr 135:2291-4 9. Whelan AP, Sutherland
WH, McCormick MP, Yeoman DJ, de Jong SA, Williams MJ 2004
Effects of white and red wine on endothelial function in
subjects with coronary artery disease. Intern Med J 34:224-8
10. Al-Awwadi NA, Bornet A, Azay J, et al. 2004 Red wine
polyphenols alone or in association with ethanol prevent
hypertension, cardiac hypertrophy, and production of reactive
oxygen species in the insulin-resistant fructose-fed rat. J
Agric Food Chem 52:5593-7