Red wine and health: Flavonoids and Free Radicals
I didn't take this kind of news lightly. So I put down the glass long enough to place a call to an expert.
Wine Research in Wisconsin - Really!
Introducing Dr. John Folts. Folts and his colleagues who study polyphenolic compounds called flavonoids in the Coronary Artery Thrombosis Research and Prevention Laboratory at the University of Wisconsin Medical School. Folts's laboratory is a library crossed with a surgical room. In one corner sits an operating table, complete with a large lighting unit, surgical instruments, defibrillators and IV tubing. Look around the walls and you see books and books and books. Folts's filing system may not be quite mis en place, but his research is impeccable and he can usually find for what he is looking.
"A lot of people think that drinking red wine will reduce their chances for heart disease, and there's some reasons why," said Folts, pointing to a slide that shows mortality associated with drinking alcohol. "We see a drop in mortality at just half a drink a day."
He's quick to point out that there is still a drop in heart disease mortality at two and three drinks a day, but, he says, mortality from other causes like cancer, liver disease and "driving, walking, that sort of thing," increases substantially with consumption of more than 3 drinks per day.
Studies going back as far as 50 years ago show that moderate intake of alcohol reduce the risk of atherosclerosis (narrowing of the arteries due to plaque accumulation), the leading cause of heart attacks and many strokes. And since, as Folts put it "very few people drink pure alcohol," the question becomes this: what in alcoholic beverages is helpful?
The answer? Flavonoids, and they're found in all plant foods, especially in grape beverages. These flavonoids have good antioxidant and anti-clotting properties.
The Role of Red Wine and Flavonoids
Numerous studies have tried to unscramble the red wine puzzle. Some studies focused on alcohol alone, but according to those study results, there's no evidence that alcohol improves much of anything. The most promising studies, according to Folts, have focused on the role of flavonoids in the prevention of atherosclerosis.
"There are three things that we in the lab and other investigators think are important in the development of atherosclerosis," said Folts. One, platelets; two, free radicals; and three, endothelial cells.
The first, platelets, help our blood to clot. Platelets also get involved in forming atherosclerosis, so in general, lower normal platelet activity is desirable. When platelets become more active or "sticky," so to speak, they adhere to artery walls (smoking is an effective way to really increase your platelet activity).
Incidentally, pure alcohol, sans flavonoids, reduces platelet activity only at high blood alcohol levels, around 0.15 b.a.c. (well over legally intoxicated). Another reason to believe that the alcohol in the wine is really of no help.
The second, free radicals, are best described as outlaw molecules. Free radicals, on a molecular level, lack an oxygen atom needed to make them stable. On their quest to mate, they can damage your arterial walls. We have all smelled a free radical. That fresh smell in the air after a thunderstorm is ozone produced by lightening. The good news is that anti-oxidants neutralize the bad oxygen molecules, thus reducing the free radical damage. Free radicals will also oxidize and damage LDL ("bad") cholesterol, which makes LDL even more of a problem in our arteries.
The third, endothelial cells, are protective cells that line all our arteries and fight off atherosclerosis. When endothelial cells are healthy, platelets slide right off the surface. When endothelial cells are damaged, they become less protective. They fall off the wall of the artery and then are found circulating in the blood. Cigarette smoking also does this to endothelial cells (sense a theme?). "We want to find something to improve endothelial cell function and to protect them," he said.
Flavonoids to the Rescue
Flavonoids are super-heroes. Flavonoids inhibit platelet activity, help neutralize the effects of free radicals, and improve endothelial cell function. Hurrah! And better yet, red wine lovers, contact with the skins and seeds of grapes is important because most of the flavonoids hang out in the skin and seeds. Red wine has ten times as many flavonoids as white wine (rose` is in between, White Zin fans).
One of Folts's collaborators did a study on rabbits that were fed high cholesterol diets for 96 days. The rabbits were then given different alcoholic beverages (red wine, light beer, and hard spirits), and alas, red wine was only one to reduce the development of atherosclerosis.
However, alcohol is not needed for the effect. One of Dr Folts's graduate students, Dhananasayan Shanmuganayagam, showed that purple grape juice would do the same thing as the red wine. In fact, de-alcoholized wine, or wine with the alcohol removed, worked just as well as wine. Ouch.
Red wine has ample amounts of flavonoids; but so do fruits, vegetables and other grape products (fruits and vegetables probably have even more flavonoids than wine). If you eat grapes remember to eat the seeds as well, as they contain important flavonoids too! (Watch the teeth.)
What it means to you
When we eat, the fat and cholesterol levels elevate in our blood stream. Having a glass of wine with dinner is a great time to have a few extra flavonoids in your blood. Unfortunately, as research has shown, red wine does not guarantee a long life free of heart disease. You also have to quit and avoid smoking, watch your weight, and keep your blood pressure in check.
This is not new information. The recommendations of dieticians and physicians everywhere stands true, dear oenophiles: Eat your fruits and vegetables (more colorful, the better), and exercise regularly (exercise also protects endothelial cells from free radicals). Free radicals come in several different forms, and since every fruit and vegetable has its own set of anti-oxidants, it is important to eat a variety of them. And as the adage goes, "moderation in everything."
So neither you nor I have to give up our evening vino. But get used to the broccoli!
Side note: I did my master's thesis on people's attitude about red wine and health. On a scale from one to seven, respondents gave it [drum roll] a 4.6. While a 7 wouldda been the optimal result, at least people seemed realistic.
March 13, 2001