Wine producers undoubtedly raised a glass to toast the discovery! They were elated when Harvard researchers Konrad Howitz and David Sinclair showed that a compound found in wine had a possible life-extending effect. Granted, they only demonstrated the effect in yeast cells, but still, an increase in life expectancy by some 70 percent was pretty dramatic. There was more excitement when Marc Tatar at Brown University blended the substance into corn mush, fed it to his fruit flies, and found they lived 30 percent longer than untreated flies. And what was this life-extending dietary supplement? Resveratrol, a compound the scientific community had long been interested in, owing to indications that it was responsible for the reputed health benefits of red wine.
Howitz and Sinclair did not set out to investigate wine. They were interested in studying the aging process, for which yeast serves as a good model since yeasts with different longevity have been identified. Why did some yeasts live longer than others? The Harvard scientists traced the effect to a specific gene, named SIR2 (“silent information regulator”), responsible for the production of an enzyme, appropriately christened “sirtuin,” that had the ability to repair damaged DNA. And what determined the activity of this gene? Nutritional status, for one! When yeast cells were starved of nutrients, they produced more sirtuin and lived longer. This meshed with the long-standing observation that animals on calorie-restricted diets have a longer life expectancy.
Humans also produce a version of sirtuin, but most people rebel at the idea of upping their production of the enzyme if it means cutting their caloric intake to the verge of starvation. What’s the point of living longer, they muse, if you are constantly so hungry that you wish you were dead? That’s why Howitz and Sinclair decided to explore the possibility of increasing sirtuin levels by other means. So they devised a laboratory test that could measure the cellular production of sirtuin, and proceeded to bathe cells in various chemical solutions to determine the response. Lo and behold, the compound that led to the most sirtuin production was resveratrol, the very substance that had already reached a near-mythical status because of its presence in red wine. Had the life-enhancing potential of red wine finally been placed on a firm scientific footing? Not exactly.
You can’t mention the connection between wine and health without bringing up the “French Paradox.” How is it that the French—who smoke excessively and eat an abundance of high-fat cheeses, sugary pastries, and foie gras—have a lower heart attack rate than North Americans? Way back in 1819, pioneer cardiologist Samuel Black noted that angina was far more frequent in Ireland than in France, and attributed this to “the French habits and modes of living, coinciding with the benignity of their climate and the peculiar character of their moral affections.” Given that French morals are not likely to offer protection against heart disease, we are left with “modes of living.” And here, the most alluring possibility, of course championed by the huge French wine industry, is the consumption of red wine.
Although scientists generally are reticent to discuss the benefits of alcohol in public, there is little doubt that four to seven alcoholic drinks a week significantly cut the risk of a heart attack. Not only that, but this amount of alcohol can also improve sugar control for diabetics, reduce the risk of stroke and prostate cancer, and even improve cognition. So what’s the worry? That the body’s response to alcohol is in the form of a “J curve,” meaning that a little drink is more healthful than abstaining or drinking to excess. Not much more than a single drink a day is linked to breast and oral cancers, and even the smallest amount of alcohol during the first trimester of pregnancy can lead to a smaller head circumference, a crude measure of brain size. Then there are the car wrecks, liver problems, and social tragedies linked to excessive consumption. So it comes as no surprise then that researchers are interested in determining just what components of alcoholic beverages are responsible for health benefits.
Resveratrol certainly would seem to be a candidate since it reduces blood clotting and, at least in laboratory studies, prevents cholesterol from being oxidized to a more dangerous form. But the Health Professionals Follow-Up Study at Harvard, which monitored over 51,000 subjects for twelve years, revealed that beer and liquor, three times a week, were more strongly associated with protection against heart attacks than red wine. It seems likely that health benefits are due both to alcohol and various other compounds, including resveratrol, found in beverages.
All the talk about red wine and its supposed wonder component has resulted in resveratrol pills appearing in health food stores. Unfortunately, though, resveratrol is an unstable compound when not in wine, so these supplements have questionable value. One product, Longevinex, claims to be packed in airtight capsules under nitrogen and has been shown to produce antioxidant effects on human cells in culture, but as of yet, it has not even been tested in mice.
In truth, the red wine evidence for the French Paradox is not strong. Maybe the answer to the mystery lies in a greater consumption of fruits and vegetables by the French or, more likely, in a lower calorie intake. In spite of their reputation for gastronomy, the French just eat less than we do. Or there may be no French Paradox at all! Some contend that French record keeping is different, and some cases described as “sudden death” are not attributed to heart disease. But here is something that has been shown: dipping apples in a resveratrol solution can significantly increase their shelf life. And you know the story about an apple a day. Here then is a way that a wine component can really improve our health. The rest of the stuff about the links between wine and health is pretty confusing . . . enough to drive a man to drink.