In 1991, CBS news "60 Minutes" in the United States stated that the reason for the French having one of the lowest rates of heart disease, even though their diet is rich in fatty foods was perhaps their consumption of wine. My essay briefly discussed the "French Paradox" broadcast of 1991; the scientific evidence that alcohol prevents death including heart attacks; and described the mechanisms by which it works using epidemiologic and laboratory studies. I also discussed the advantages of wine and how it is believed to be even more healthful than alcohol.
Drinking two glasses of wine daily probably adds three to four years to one's life expectancy.
The French paradox. On November 17, 1991, 21.8 million American and Canadian households tuned in CBS news "60 Minutes" and learned about the French paradox. Why, with the French affinity for fatty cheeses, foie gras and rich heavy sauces, would the people of France have one of the lowest rates of heart disease, much lower than Americans and Canadians. The host of the program held up a glass of red wine, and proclaimed the answer to France's low rate of Heart disease "may lie in this inviting glass".
The explanation given on television that night was the consumption of alcohol, citing red wine in particular and the explanations given were supported by scientific data. The public as a result decided to try the theory for themselves. Between 1980 and 1990 red wine sales in the United States had decreased by 4.5% but following the T.V. broadcast in 1991, the sales for red table wine in 1992 increased by a whopping 39%.
My essay tonight will briefly discuss the "French paradox" broadcast of 1991, the scientific evidence that alcohol helps prevent heart attacks, and describe the mechanisms by which it works.
I will also discuss the way in which wine is different from other kinds of alcohol, and how it might be even more healthful than alcohol as a result.
When CBS was doing research for the T.V. program in 1991 on why the French remain healthy in spite of their diet, they interviewed Dr. Serge Renaud, a French scientist and Director with the Research Unit on Nutrition and cardiology at the French National Institute of Health Research in Lyons, France. He is half French, half Canadian, and came to Canada from France to study at age 20 (in the early 1950's). He was absolutely astonished that there was a population n the world that didn't drink wine with meals.
He very quickly became aware also that North Americans eat very little fruit and that the coronary heart disease rates in America were much higher than in France even though the French eat far too much in dairy products. For most countries, an increase in milk fat consumption inevitably leads to an increase in heart disease.
He commented on the fact that the French who drink larger quantities of wine, were found to be at lower risk of heart disease than the British who consumed the same amounts of milk fat but less wine.
Dr. Renaud stated that "nobody knows for sure what the perfect amount of wine for anyone who wants to optimize its health benefits but he advised to drink moderately (one to two drinks per day), preferably with meals, avoid drinking binges completely and a moderate diet. In his case he eats a great deal of bread. At noon he eats vegetables, fruit and yogurt. In the evening more bread and vegetables with a little bit of meat or fish. And, of course, there's the wine.
What is the evidence that alcohol prevents heart disease?
Epidemiology collects data from large populations, and then uses analytic techniques to infer relationships between conditions, such as diet and exercise, and diseases, such as heart attacks or cancer.
In the 1970s, Dr. Arthur Klatsky, a cardiologist with Kaiser Permanente health organization in California which provides comprehensive long-term health care for more than 100,000 people reviewed their computerized health care records to see if he could find factors that significantly affected the risk of heart disease. He found that abstaining from alcohol proved to be a risk factor independent of other risk factors. Drinking actually seemed to make the heart healthier. In later numerous studies, Dr. Klatsky confirmed that moderate drinkers, those who consume one to three drinks a day, have a lower risk of dying from heart disease than either those who abstain altogether or those who drink heavily, a pattern of results known as a u-shaped (or j-shaped) curve. This relation has been confirmed by researchers in many different countries working with widely divergent populations.
A word of caution. Some people are unable to drink moderately, e.g. those belonging to alcoholics anonymous, and heavy drinking raises the risk of some heart diseases and of death from all causes far above those associated with abstention. Let us not forget the social costs of alcohol abuse, including drunk driving and its effects on our society. Indiscriminate advice to non-drinkers to take up alcohol for health reasons is inappropriate.
The alcohol's major positive effects appear to be targeted directly at coronary heart disease and also appears to lower the risk of stroke. In fact, many studies find that moderate drinkers are at lowest risk of mortality from all causes - that, they simply live longer than heavy drinkers, or those who don't drink at all. The crucial consideration is that the effects of alcohol are dose-related.
A point of clarification. One drink equals 12 oz. of beer, 1.5 oz of liquor or 5 ounces of wine.
Overall, people living in North America are very modest consumers of alcohol. Dr. Klatsky reviewed the health records of 129,000 people and found that only 8% consumed more than three drinks a day. A study of 51,000 American health professionals by Dr. Eric Rimm at the Harvard School of Public Health found that only 3.5% consumed more than 3 to 4 Drinks per day. In other words, the vast majority of Americans who drink already fall in the moderate drinking category.
From several large epidemiologic studies, the reduction in risk of heart disease in those persons consuming 1 to 2 Drinks at day is 25 to 45%.
Alcohol appears to help by working against long-term clogging through atherosclerotic plaques forming within the blood vessel walls. Alcohol increased hdl levels (the good cholesterol) and reduced ldl (the bad cholesterol) levels. And alcohol also prevents short-term blockage, or thrombosis, by reducing the tendency of blood to form clots that can totally shut oft the flow of blood to the heart.
An epidemiologic study was done in Boston involving 340 men and women who had suffered heart attacks matched with people who had similar physical and socio-economic traits but who had not had heart attacks. All the subjects were interviewed about their dietary and life-style patterns, and their blood was analyzed. The researchers found that alcohol consumption was associated with increased levels of hdl's which co-related to decreased risks of a heart attack. The evidence in this study suggested that approximately 50% of the reduction in risk attributable to alcohol consumption was explained by the changes in total hdl's.
Dr. Renaud (our French paradox scientist) studied 1,600 men from South Wales that matched information about their dietary habits, including alcohol consumption with blood studies focusing on the ability of the blood to form clots. There was a correlation between alcohol consumption and the development of clots. Those consuming alcohol had a lesser degree of clot formation. Other studies add to the evidence. Researchers from the Montreal Heart Institute tested blood samples from 12 healthy people before and after they drank two ounces of cognac. Alcohol consumption in this study markedly inhibited a clot forming (through platelets in the blood coming together to form a clot (thrombus)). Alcohols ability to diminish thrombosis is perhaps even more important than its longer-term effect on arterial clotting through the formation of atherosclerotic plaques inside the arterial blood vessel.
After the French paradox appeared on American T.V., Klatsky (from Kaiser Permanente) re-examined his data to see if he could discover any advantage wine has over other alcoholic beverages among the patients studied at Kaiser Permanente, the analysis did in fact show that wine drinkers had lower risks of mortality than the others, both from cardiovascular diseases and from all causes. "Wine drinkers did better."
Wine is 85% water, 12% alcohol and the remainder consists mostly of solids extracted from grapes, including sugars, acids and phenolics. The phenols including the colouring matter, tannins and literally hundreds of other compounds and most importantly all phenols are antioxidants.
The phenols in the wine decreases the oxidative transformation of "bad" cholesterol in the body called low density lipoprotein (ldl) cholesterol. As a result oxidized ldl cholesterol is prevented from accumulating on the blood vessel walls, which if untreated could narrow an artery to eventually block blood flow causing a heart attack. Anti-oxidants such as vitamin E and Beta-carotene which may protect ldl cholesterol from this damage have been shown to reduce the risk of heart disease. It is believed that the anti-oxidants in wine prevent atherosclerosis by inhibiting the oxidation of ldl cholesterol.
In the laboratory, blood from healthy volunteers had various combinations of antioxidants added to the samples to examine their effects on ldl. The red wine components were significant inhibitors of ldl oxidation, their effects even stronger than vitamin E.
The phenols in wine which are antioxidants are derived largely from the skins of grapes and their concentrations vary by grape variety and wine-making techniques. Since skin contact is essential to their extraction, red wine contains significantly higher levels of phenols than white.
I am going to discuss the three main phenols in wine: quercetin, catechin and resveratrol.
Quercetin (which is also abundant in onions and apples, as well as other fruits and vegetables), and catechin are normal constituents of grapes. Resveratrol is a natural protective chemical produced when grapes are attacked by fungus, so its presence is determined by the amount of disease pressure during the growing season, normal quercetin levels are 10 times higher than resveratrol than quercetin.
Eight hundred Dutch men were studied over a five year period. Those who consumed large amounts of antioxidants in tea, apples and onions were only half as likely to get heart disease as those who consumed small amounts. Two glasses of wine a day would definitely put you in the top category of antioxidant consumption.
A Florida scientist has demonstrated that a component in grape skins causes blood vessels to dilate increasing blood flow and reducing the risk of heart attacks from arterial clotting or blockage.
A 1990 French study compared cholesterol levels and platelet aggregation in blood samples taken from people who had been given diluted alcohol, white wine and red wine. Red wine was the only one that both decreased aggregation, or clotting, and increased hdl. "Red wine had different effects to those induced by pure ethanol" and the researchers felt that it was the tannins present in the wine especially red wine.
In conclusion, wine isn't another form of alcohol. In many ways, it's only well preserved fruit. We know that a diet high in fruit and vegetables is good for you, and one of the reasons is that they are high in antioxidants. Wine is too. White wine is just as rich as many fruits and vegetables but red is even higher.
Drinking two glasses of wine daily probably adds three to four years to life expectancy as compared with not drinking at all, and heavy drinking of eight to ten years less life.
My advice to you, two glasses of wine a day will help keep the Doctor away.
