Friday, March 26, 2010

Wine boosts the body’s antioxidant system

It’s hardly news that wine contains powerful antioxidants, just like other superfoods including blueberries, acai, and pomegranates. What isn’t so obvious though is how these compounds are absorbed into the body and whether or not they actually do any good. This problem of how food-derived nutrients, along with drugs and supplements, are taken up and delivered to “target” tissues throughout the body is called “bioavailability.” There are numerous compounds that perform miracles in a test tube but just aren’t absorbed very well from the digestive tract when taken orally. Resveratrol is a classic example of this; with more than 3,000 research articles published, it’s considered a fountain of youth in a pill (or a glass of wine) by many, but it turns out to have poor bioavailability. There must be something else in wine that explains its long list of health benefits.

Researchers at 2 universities in Spain provided some insight into the role of wine as an antioxidant in a recent study. They used eight volunteers who consumed a standardized diet low in antioxidants, and compared the antioxidant capacity of their blood plasma with and without the addition of red wine to the diet. Samples were taken at days 2 and 7 of the regimen, during the week with wine and without. A significant increase in antioxidant capacity was observed with wine in the diet, as one would hope. (A similar study was done in Chile several years ago, with similar findings and also noting that wine was better than vegetables high in antioxidant vitamins.) This proves that something in the wine is being absorbed and circulated through the body, and having a positive effect. It is probably not resveratrol though, as previous studies of this type have shown that it does not achieve significant levels in the blood after oral ingestion.

Interestingly, dark chocolate is another superfood that has measurable effects when eaten. In this case, it causes the blood vessels to relax and lowers the blood pressure. The cocoa-derived compounds responsible are much the same as antioxidant molecules found in red wine, known as flavonoids. What is important here is to distinguish between studies that actually test what happens in a clinical experiment from what occurs in a laboratory test. Too many supplements are rushed to market based on an incomplete understanding of how they actually work in the human body. It seems we always come back to the point where drinking wine and eating the right foods works better than popping pills. Who would have thought?

Thursday, March 18, 2010

Wine may help breast cancer patients receiving radiation

Despite advances in screening and early diagnosis of breast cancer, little has changed in how it is treated over the past ten or twenty years. For most women, it comes down to a choice of mastectomy or removal of the tumor (lumpectomy) and radiation. If it has spread, then chemotherapy is recommended. The good news for women choosing mastectomy is that breast reconstruction techniques have improved substantially, but for patients opting for “breast conserving therapy” an ordeal of several weeks of radiation treatment is still standard treatment. And despite the fact that the breast is conserved, the radiation causes irreversible changes and even some disfigurement on top of the dent left after the lumpectomy. But now there is some evidence that wine may help prevent some of these changes, despite lingering controversy about the role of alcohol in breast cancer risk.

The data comes from a study from the Catholic University in Campobasso, Italy, a center where wine and health research has been particularly fruitful in recent years. The researchers assessed skin toxicity (redness, irritation) from radiation in each of 3 groups of women receiving different treatment doses. Overall, women who drank wine had a lower incidence of skin toxicity compared to nondrinkers (22% vs. 38%), and the amount of daily drinking had an influence as well. Women who drank a half a glass or less had a 32% incidence, while only14% of those consuming a glass a day experience significant skin irritation. However, the percentage increased as drinking increased above a glass a day, with 2 glasses about as high as none. Those who are familiar with my book Age Gets Better with Wine will recognize this as a J-shaped curve, where moderate drinkers enjoy benefits not associated with abstinence or heavy drinking.

Earlier reports on various types of cancer have revealed that polyphenol molecules in wine, including but not limited to resveratrol, have the effect of protecting cells from the toxic effects of radiation while simultaneously sensitizing cancer cell to it. That would provide an explanation to the findings of this clinical study. What isn’t known, and cannot be directly inferred from this type of study is whether supplements of wine-derived compounds will have the same effect. Clinical trials should provide the answers within the next few years.

Tuesday, March 9, 2010

Is red wine the new women's diet drink?

Why is it that we act so surprised when each new study showing that wine is a healthy drink comes out? This week it was a very large study from Brigham and Women’s Hospital in Boston, showing that women who drink red wine are less likely to gain weight. To be fair, although there are several studies already pointing in that direction, this one adds heft to the data because of its size (nearly 20,000 women) and length of follow-up (nearly 13 years.) But if you have read my book or have been following my posts here, your response is more likely to be “well, duh.”

Here are the particulars: The study, published in the Archives of Internal Medicine, identified a population of middle-aged women of normal weight and recorded their lifestyle habits as a baseline. Over the period of follow-up, some 42% became overweight and 4% obese, as determined by Body Mass Index. After statistically adjusting for factors such as exercise habits, smoking, and non-alcohol caloric intake, they found that moderate drinkers were much less likely to gain weight as compared to nondrinkers. The pattern was most dramatic for women who drank red wine.

We do know of course that people who drink red wine regularly and in moderation have other healthy habits, but a significant aspect of this study is that those factors were neutralized. There is clearly something more to the red wine connection than just being a marker for a better diet or regular exercise. This study doesn’t tell us what that might be, but we have some ideas, don’t we?

Monday, March 8, 2010

Is resveratrol the new aspirin for heart attacks?

The newswires are abuzz this month about a recent report suggesting that resveratrol, the polyphenol molecule from red wine, helps restore blood flow and limit muscle damage after heart attack. The typical headline reads something like “Red wine component pill successful during heart attacks” or something similar, with the clear implication that some sort of clinical trial has been done. In fact, it was a study in mice, and while the results were impressive it is only one small step toward the giant leap of clinical practice. What happens in mice doesn’t always happen in humans, so we are no where near the point where your cardiologist is going to give you a resveratrol pill when you show up in the E.R. with chest pain.

Nevertheless, the results are encouraging. What happens in a heart attack is that the plaques that build up in the coronary arteries that feed the heart muscle cause a clot to form, completely obstructing the vessel and depriving the heart of oxygen. It’s similar to what happens to the brain in a stroke. This oxygen starvation is called “ischemia” and when the clot is dissolved and blood flow re-established, it is called “reperfusion.” Paradoxically, this rush of blood flow releases toxins that have built up in the cells, resulting in what is called “ischemia-reperfusion injury.” Transplant surgeons deal with a related issue. The ability of resveratrol to counteract the detrimental effects of ischemia-reperfusion has been well documented in numerous studies, and the recent one in mice confirms those findings. But a mouse heart is tiny, and the question of whether the same effect applies in the large muscle mass of the human heart remains speculative.

A likely scenario is that one of the synthetic derivatives of resveratrol, many of which are much more potent, will emerge as a viable therapy for heart attack and stroke. But clinical studies on resveratrol are few in number, as I have pointed out here recently.

Thursday, March 4, 2010

The politics of drinking: is there room for moderation?

Much political hay has been made after President Obama’s recent physical exam, with the doctor’s recommendation of “moderation of alcohol intake.” The polarized lens through which American political debate is viewed sees this as an indictment of the president’s drinking habits, as though any level of alcohol consumption sets a bad example, and there is no middle ground between alcohol abuse and abstinence. But as we know, at least in the case of wine, the healthiest place to be is moderate drinking (see “modern view of moderation” posted February 15.) Abstinence and excess share the same risk profile for heart disease and many other conditions; it’s the moderates who are the clear winners here, but I will leave it up to you to interpret the political parallels.
The president’s cholesterol has been creeping up too, and dietary changes were recommended. Here’s where the opportunity for what is called these days a “teachable moment” was missed. Moderate drinking, especially wine with meals, is one of the more effective means of improving cholesterol profiles. In fact, in the words of Dr. R. Curtis Ellison, Professor of Medicine and Public Health at Boston University School of Medicine, “…only stopping smoking would have a larger beneficial effect on heart disease than for a non-drinker to begin having a drink or two each day.” But our government has a long and proud tradition of suppressing information about healthful drinking, as I describe in my book.
See the full report on the president’s exam here: