Does a glass of wine a day really keep the heart doctor away? Nantucket Cottage Hospital’s visiting cardiologist, Dr. Joseph Garasic, investigates the facts and fictions behind the French Paradox.
The idea that wine has miraculous health benefits is common cocktail party banter. “A toast to our health,” someone will say, raising a glass of wine. “Really, my cardiologist says that wine is good for the heart.” What is being referred to here is the epidemiologic phenomenon known as the French Paradox, the observation that the French — lovers of cheese, butter, pork and cigarettes — have lower rates of cardiovascular disease than other countries with seemingly healthier diets and lifestyles. For example, in one study, residents of Toulouse, France were shown to have an intake of cholesterol and saturated fat much higher than among residents of the United States, and more akin to levels seen in Belfast, Scotland. However, coronary heart disease mortality in Toulouse was 1/3 to 1/6 of that in Belfast. And it’s all because of wine, or so the French Paradox goes. Since the theory hit American audiences by way of a “60 Minutes” episode in 1991, US wine sales soared and everyone wants to know if we can really find good heart health in a glass. So what are the facts behind the French Paradox?
While alcohol has been used medicinally for centuries, the modern association between alcohol and cardiovascular health is considerably more recent. A paper in the British Medical Journal combined data from eighty-six prior studies investigating the association between alcohol consumption and many types of cardiovascular disease, coronary artery disease, and stroke. Compared to non-drinkers, alcohol drinkers had a 25% reduction in death from cardiovascular disease, a 29% reduction in the occurrence of coronary artery disease, and no significant difference between groups in the occurrence of having or dying from a stroke. Moreover, the lowest risk of dying from coronary artery disease was observed in those who had one to two alcoholic drinks daily. Moderate alcohol consumption, it seemed, really was good for us.
But don’t go trading in your gym membership for a wine-of-the-month club just yet. For those that wonder if a little alcohol is good, perhaps more is better, multiple studies have also shown an increase in death and hemorrhagic stroke (bleeding in the brain) with heavy alcohol consumption. Likewise, heavy drinking has been linked to high blood pressure, fatty liver and cirrhosis, and weight gain. Not to mention more bad decisions that seemed like good ones at the time. Given these issues, before any physician widely recommends alcohol as medicine, the French Paradox needs to emerge as a bit less paradoxical and considerably more grounded in scientific fact.
If one assumes that the decrease in cardiac events seen in France is in fact due to wine consumption, the next step then is to explain how low to moderate alcohol consumption may positively influence health. Perhaps it is the alcohol itself that reduces heart disease and saves lives, though data to support this theory is scant. Could there be other elements in wine that are beneficial? Leading candidates for consideration are resveratrol, procyanidins and polyphenols. Resveratrol is an anti-oxidant, anti-inflammatory compound found in relatively high concentrations in red wine, and derived from the skin of grapes. In the prevention of cardiovascular disease, resveratrol is believed to decrease the oxidation of low-density lipoprotein (LDL or bad) cholesterol and inhibit the aggregation of platelets. In cardiology speak, both are very good things for your heart.
There is also developing data on resveratrol as a contributor to longevity and its use in the treatment and prevention of cancers, diabetes and Alzheimer’s disease. In one study from 2003, resveratrol appeared to increase the life span of yeast cells by 70%. Alas, it was the life span of lowly yeast cells and not of humans — a far cry from the fabled fountain of youth. It is also not clear that we can consume enough resveratrol from red wine to achieve the potential health benefits seen in almost exclusively non-human experiments. How much wine would we need to consume? One thousand liters of red wine per day is the requisite amount, far too much for even the most voracious oenophile.
The other compounds to consider are Procyanidins, anti-oxidant agents found in tannins. Present in higher concentrations in some French red wines than in other wines, they are potentially linked to improved cardiovascular outcomes. Possible benefits include improved health of the blood vessel lining, decreased oxidation of good and bad cholesterol, and reduced blood pressure among others. Whether procyanidins represent a link to the success of the French lifestyle is as yet unproven.
While it is possible that moderate consumption of alcohol is the key to longevity and cardiovascular health, it is as likely that some other trait common to French culture is more in play. When Americans visit France, for example, many are highly impressed by the plentiful cheeses, breads and rich meals. However, eating like an American visiting France is not the same as eating a diet typically consumed by a French national. Reported rates of obesity are considerably lower in France than in the United States. How can this be?
To begin, overall caloric intake and portion size are both lower in France. The French generally eat three meals per day and do not snack between meals. Not only do Americans tend to snack between meals but those snacks are often high in fat (particularly trans-fats), low in nutrition and have a high refined sugar content. So, it is possible that while we draw attention to the high fat intake in the French diet, some would argue that the French diet contains naturally occurring fat from butter and cream and that these types of non-trans, non-hydrogenated fats are easier for the body to break down. Thus, other aspects of the French diet may be much healthier than the American diet and may play a substantial role in the apparent French Paradox, when in fact there is no paradox at all. Rather, the French experience is characterized by people eating smaller amounts of generally healthier food, thus protecting themselves against cardiovascular disease.
In the end, the French Paradox and the potential cardiovascular benefits of wine and moderate alcohol consumption will likely continue to be an intriguing hypothesis, supported by a large volume of population-based observational research, but lacking the Holy Grail of medical proof. To definitively answer the question at hand, a randomized study would be necessary wherein half of the study subjects drank wine moderately and half of the subjects did not. Cardiovascular event rates and mortality would then be compared in each group after a period of follow up. Such a study would require a large number of subjects, would be costly to undertake, and may require a long period of follow up. As a result, there is no prospective, randomized human data available to us in clarifying the veracity of the French Paradox, nor any on the immediate horizon. Thus, doctors will continue to grapple with whether or not to encourage alcohol consumption among their patients, not knowing for certain that the science supporting the paradox is as ironclad as we would like.The reason then to drink wine is for love of the romance, history and collegiality it brings. And maybe, just maybe, it is good for you as well.