Wine & Health
A Look at the Latest Research and Most Promising Discoveries
(article from Wine Spectator, May 31, 2009)
Each week seems to bring forward a new study on the health benefits of moderate wine consumption. Evidence continues to mount that wine drinking goes hand in hand with a healthy lifestyle and is a powerful means of preventing heart disease. In addition, there has been solid research over the past few years regarding how wine may help prevent or relieve the effects of dementia, diabetes and even osteoporosis.
Many of the recent discoveries involve a compound in wine called resveratrol. What began as research into the unexplained health benefits of wine has turned into a fascinating quest to realize one of mankind's greatest dreams: to prolong the human life span. For more on scientists' efforts to unlock the potential power of resveratrol, see "Harnessing Wine's Healing Powers".
As in any area of scientific inquiry, the findings presented in this report should be viewed in context. The conclusions of any single study or group of studies are always subject to ongoing research. With that in mind, we interviewed six leading researchers and physicians for their advice on how to incorporate wine into a healthy diet.
As always, however, you must ultimately be your own advocate. Use this guide as a broad outline to help inform your decisions about wine and your health, and be sure to consult your physician before embarking on any new lifestyle regimen.
A USER'S GUIDE TO WINE SCIENCE
Summaries of recent findings and what they may mean for wine drinkers
by Kim Marcus and Jacob Gaffney, Wine Spectator, May 31, 2009
Tending to The Heart
The most important factor in gleaning health benefits from wine appears to be the amount of wine consumed. Many studies have shown that regular and moderate consumption (one to two glasses per day) of red wine is associated with the greatest amount of benefits, such as better circulation and overall heart health.
A fascinating new angle of study is being pursued by researchers at Stanford University, who have discovered that one of the factors behind alcohol's effect on the heart is that it activates an enzyme called aldehyde dehydrogenase 2. The enzyme, which helps process alcohol, also eliminates toxic byproducts created by the breakdown of fats in cells during a heart attack. Eliminating the byproducts prevents additional damage to the heart cells.
Several studies have not only amassed evidence that moderate wine-consumption may help delay the onset of Alzheimer's disease and other forms of dementia, but are also now detailing the complicated physiological processes at play.
Two proteins known as amyloid-beta peptides are associated with Alzheimer's. These long protein strands tend to clump together, forming plaques that kill surrounding brain cells. Researchers at the University of California, Los Angeles, and the Mt. Sinai School of Medicine in New York have found that grape seed polyphenols block the formation of the plaques. "If the amyloid-beta proteins can't assemble, toxic aggregates can't form, and thus there is no toxicity," says David Teplow, a UCLA neurology professor. "our work in the laboratory suggests that administration of the compound to Alzheimer's patients might block the development of these toxic aggregates, prevent disease development and also ameliorate existing disease."
Researchers in Sweden have found that drinking an average of five to 10 glasses of wine per week may cut the risk of developing rheumatoid arthritis by up to 50 percent, compared with the risk to nondrinkers.
In addition, other studies have found that moderate wine-drinking is linked to increased bone density in elderly women, possibly lowering their risk of osteoporosis.
Demystifying Wine Headaches
What causes some people to suffer headaches after drinking wine? Frederick Freitag, associate director of the Diamond Headache Clinic, says identifying the specific triggers that cause these headaches can be tricky, as there are different types of headaches that people experience when they drink wine. "There is a unique headache associated with red wines, which is different from the headache some people get from drinking wine of any sort, which is different still from the migraines some patients experience related to wine ingestion," he says.
Still, some conjectures can be ruled out. Freitag believes histamines, which are found in higher amounts in red wine, are an unlikely cause of headaches, as they exist in greater levels in other frequently consumed foods. "There is more histamine in 4 ounces of fish or a serving of eggplant than in 4 ounces of red wine," he notes, adding that a more common allergic reaction to histamines is a stuffy nose.
Similarly, the small amount of sulfites found in wines is often mistakenly identified as a headache-causing agent. These sulfites are also found in other food sources, such as dried fruit, baked goods and pickled vegetables. A serving of dried apricots, for example, contains almost 10 times the amount of sulfites of a serving of wine. And an allergic reaction to sulfites usually involves breathing trouble and rashes, not headaches.
Headaches could be triggered by the alcohol in wine, says Freitag, which would explain why red wine, which is generally higher in alcohol, seems to pose more problems for certain people. Another possible culprit is tyramine, an amino acid derivative that is produced during fermentation. Tyramine is especially suspected "for triggering migraines in up to about 40 percent of the migraine population," according to Freitag.
Heading Off a Cold
The Mayo Clinic recommends avoiding alcohol when you have a cold, because alcohol can contribute to dehydration. The good news, however, is that wine drinkers may be less likely to come down with colds in the first place. One Spanish study showed that participants who regularly drink eight to 14 glasses of wine a week are half as likely to develop a cold as those who drink beer, spirits or no alcohol at all.
Keeping the Flu Away
Researchers at the University of South Carolina say that a chemical found abundantly in red wine, apples and onions helps protect against influenza, especially after a rigorous respiratory workout, when the body is more susceptible to infection. The chemical, a polyphenol called quercetin, is a known anti-inflammatory found in the skins of fruit and vegetables.
Prior studies have theorized that quercetin helps reduce lung inflammation and inhibits the growth of prostate cancer. The specific anti-viral properties of quercetin remain unknown, but researchers speculate that the compound may block the ability of the influenza virus to replicate itself.
Lowering Diabetes Risk
People who consume moderate amounts of wine daily appear to be at an advantage when it comes to preventing type 2 diabetes; studies have shown that light to moderate drinkers may have a substantially lower risk of developing the disease. A Harvard School of Public Health study from 2003 found that women 25 and older who consumed a glass or two of alcohol a day were at a 58 percent lower risk of developing diabetes than nondrinkers.
Researchers speculate the alcohol consumption, and red wine specifically, might help regulate insulin sensitivity and blood glucose levels by slowing the passage of glucose through the digestive tract. Those diagnosed with diabetes may benefit from drinking wine as well - the risk of coronary heart disease was up to 55 percent lower in studies for diabetics who drank alcohol in moderation.
Wines vary somewhat in nutritional content, but the USDA National Nutrient Database for Standard Reference, which lists general nutritional information for table wines, reveals that the carbohydrate counts are lower than you might think. The average 5-ounce glass of Cabernet Sauvignon comes in a t 3.82 grams of carbohydrates; Merlot is similar, at 3.69 grams. A serving of non-light beer has more than twice the carbohydrates, and a sweetened soft drink may have up to 10 times the amount.
In addition, researchers in Spain report that the grapes used to make red wines contain significant levels of fiber. They've found that the fiber and antioxidants in Tempranillo in particular seem to reduce blood pressure and cholesterol better than other sources of dietary fiber, specifically oats and psyllium. The study is a follow-up to earlier experiments conducted by the same team that found that drinking 300ml or red wine per day increased soluble dietary fiber intake in Spanish men.
Reducing Throat Cancer Risk
Drinking wine in moderation may offer protection from the onset of Barrett's Esophagus, a precursor to esophageal cancer, according to a study released in March. Researchers found that subjects who consumed between seven and 14 glasses of wine weekly lowered their chances of developing the disorder by 56 percent. Barrett's Esophagus occurs when gastroesophageal reflux disease, or chronic heartburn, permanently damages the cells of the esophagus; the abnormal healing of the esophagus can lead to a cancer called adenocarcinoma. "Red wine and many foods, such as fruits and vegetables, contain antioxidants. It appears antioxidants may decrease the risk of getting Barrett's Esophagus," explains Douglas Corley, a gastroenterologist and one of the study's lead researchers.
Exercising and Wine
According to Douglas McKeag, director of the Indiana University Center for Sports Medicine, it is not "bad" for you health if you mildly imbibed prior to exercise; it does stimulate the heart somewhat, but so does a pre-workout warmup. Other physiological effects of alcohol in moderation include dilation of the peripheral blood vessels and relaxation of the muscles.
But McKeag also warns of the unwanted, even potentially dangerous depending on the type of athletic pursuit, effects of too much alcohol, such as sedation and inhibition of judgment. If a meal with wine is scheduled prior to your exercise session, McKeag advises limiting your consumption to one glass.
In a study published online by the Journal of the Science of Food and Agriculture, several winegrapes traditional to France and Italy were found to be rich in melatonin, a hormone that not only tells the body it's time to turn in for the night, but also acts as a powerful antioxidant and detoxifies cells. Eight varieties were tested in the study; Nebbiolo was found to contain the most melatonin, followed by Croatina, Barbera, Cabernet Sauvignon, Sangiovese, Merlot, Marzemino and Cabernet Franc. Alcoholic drinks before bedtime are discouraged by the National Heart, Lung and Blood Institute, however: "Alcohol robs you of deep sleep and REM sleep, keeping you in the lighter stages of sleep," the institute's healthy-sleep guide says.
Producing Fatty Acids
European scientists have linked moderate alcohol consumption, especially wine drinking, to higher levels of omega-3 fatty acids in the blood. These fatty acids, prevalent in oily fish, have been found to help lower the risk of heart disease. While the body cannot manufacture these fatty acids, it can apparently synthesize omega-3 from everyday vegetable oils with the help of alcohol.
Drinking Flawed Wines
Concerned about those off scents coming from your wine bottle? They could be caused by TCA (2,4,6-trichloroanisole), a chemical that contaminates the corks, or by excessive growth of brettanomyces, a common yeast present in most fermented beverages. The former produces smells such as mold of wet cardboard, while the latter can be identified by aromas such as leather or barnyard.
Despite the unpleasant scents, enologist Pascal Chatonnet of the University of Bordeaux reports there is nothing dangerous about them. Regarding the safety of drinking either corked wine or wine showing brettanomyces, he says, "Don't worry about your health, there is absolutely no risk. However, there is also no pleasure in tainted wines."
Wine and Health Glossary
Alcohol dehydrogenase ~ Enzyme found in the digestive tract that helps the body break down alcohol. Women typically produce less alcohol dehydrogenase than men (and so metabolize alcohol more slowly).
HDL cholesterol ~ High-density lipoprotein (HDL) cholesterol, aka "good cholesterol" in that it contains more proteins and less fat. A level of 60mg/dl of HDL is generally considered protective against heart disease by reducing inflammation in blood vessels and inhibiting the buildup of fatty deposits in the arteries. Low-density lipoprotein is known as "bad cholesterol"; an LDL of less than 100mg/dl is considered optimal. HDL cholesterol mops up LDL cholesterol and transports it to the liver, which breaks it down.
Polyphenols ~ A class of chemical compounds found in plants, polyphenols fulfill a variety of functions, from providing color in fruits to fighting off infections; high levels are also found in the skins of grapes and other fruits. Polyphenols are divided into two classes: flavonoids and nonflavonoids. Flavonoids, which are abundant in wine, include flavonols, procyanidins (condensed tannins) and anthocyanins. The levels of these compounds greatly influence the overall taste, color and longevity of finished wines. Tannins are the most abundant polyphenol among the 4,000 found in the plant world. Several polyphenols, including procyanidins and quercetin, are being studied for their potential health benefits.
Resveratrol ~ A polyphenol that functions as a plant's primary defense against damage from bacteria or fungi. Found in grape skins and red wine, resveratrol is the subject of intense study for its potential role in prolonging the human life span and in guarding against dementia, diabetes and cancer.
SIRT1 ~ A human gene, part of a family of genes called sirtuins, being researched for its role in the aging process. SIRT1 may be activated by resveratrol and other polyphenols.