Health effects of wine

Wine and health is an issue of considerable discussion and research. Wine has a long history of use as an early form of medication, being recommended variously as a safe alternative to drinking water, an antiseptic for treating wounds, a digestive aid, and as a cure for a wide range of ailments including lethargy, diarrhea, and pain from child birth.

Ancient Egyptian Papyri and Sumerian tablets dating back to 2200 BC detail the medicinal role of wine, making it the world's oldest documented man-made medicine. Wine continued to play a major role in medicine until the late 19th and early 20th century, when changing opinions and medical research on alcohol and alcoholism cast doubt on the role of wine as part of a healthy lifestyle and diet.

In the late 20th and early 21st century, fueled in part by public interest in reports by the United States news broadcast 60 Minutes on the so-called "French Paradox", the medical establishment began to re-evaluate the role of moderate wine consumption in health.

Historical role of wine in medicine
Early medicine was intimately tied with religion and the supernatural, with early practitioners often being priests and magicians. Wine's close association with ritual made it a logical tool for these early medical practices. Tablets from Sumerian culture and papyri from Ancient Egypt dating to 2200 BC include recipes for wine based medicines, making wine the oldest documented man made medicine.

Early history
When the ancient Greeks introduced a more systematized approach to medicine, wine still retained its prominent role. The Greek physician Hippocrates considered wine a part of a healthy diet, and advocated its use as a disinfectant for wounds, as well as a medium in which to mix other drugs for easier consumption by the patient. He also prescribed wine as a cure for various ailments ranging from diarrhea and lethargy to pain during childbirth. The medical practices of the ancient Romans involved the use of wine in a similar manner. In his 1st-century work De Medicina, the Roman encyclopedist Aulus Cornelius Celsus detailed a long list of Greek and Roman wines used for medicinal purposes. While treating gladiators in Asia Minor, the Roman physician Galen would use wine as a disinfectant for all types of wounds, and even soaked exposed bowels before returning them to the body. During his four years tending to the gladiators, only five deaths occurred, compared to sixty deaths under the watch of the physician before him.

Religion still played a significant role in promoting wine's use for health benefit. The Talmud noted wine to be "the foremost of all medicines: wherever wine is lacking, medicines become necessary." In his first epistle to Timothy, Paul the Apostle recommended that his young colleague drink a little wine every now and then for the benefit of his stomach and digestion. While the Islamic Koran contained restrictions on all alcohol, Islamic doctors such as the Persian Avicenna in the 11th century AD noted that wine was an efficient digestive aid but, because of Islamic laws, were limited to only using it as a disinfectant while dressing wounds. Catholic monasteries during the Middle Ages would also regularly use wine for various medical treatments. So closely tied was the role of wine and medicine that the first printed book on the subject of wine was written in the 14th century by a physician, Arnaldus de Villa Nova, with lengthy essays on wine's suitability for treatment of a variety of medical ailments such dementia and sinus problems.

Risks of consumption
The lack of safe drinking water during much of history may have been one reason for wine's popularity in medicine. Wine was still being used to sterilize water as late as the Hamburg cholera epidemic of 1892 in order to control the spread of the disease. However, the late 19th century and early 20th century ushered in a period of changing views on the role of alcohol and, by extension, wine in health and society. The Temperance movement began to gain steam by touting the ills of alcoholism, which was eventually defined by the medical establishment as a disease. Studies of the long and short-term effects of alcohol caused many in the medical community to reconsider the role of wine in medicine and diet. Public opinion turned against consumption of alcohol in any form, leading to Prohibition in the United States and other countries. In some areas, wine was able to maintain a limited role, such as an exemption in the United States for "therapeutic wines" that were sold legally in drug stores. These wines were marketed for their medicinal benefits, but some wineries used this measure as a loophole to sell large quantities of wine for recreational consumption. In response, the United States government issued a mandate requiring producers to include an emetic additive that would induce vomiting above the consumption of a certain dosage level.

Throughout the mid to early 20th century, health advocates pointed to the risk of alcohol consumption and the role it played in a variety of ailments such as blood disorders, high blood pressure, cancer, infertility, liver damage, muscle atrophy, psoriasis, skin infections, strokes, and long term brain damage. Studies showed a connection between alcohol consumption among pregnant mothers and an increased risk of mental retardation and physical abnormalities in what became known as fetal alcohol syndrome, prompting the use of warning labels on alcohol-containing products in several countries.

French paradox and the benefits of consumption
The 1990s and early 21st century saw a renewed interest in the health benefits of wine, ushered in by increasing research suggesting that moderate wine drinkers have lower mortality rates than heavy drinkers or teetotalers. In November 1991, the U.S. news program 60 Minutes aired a broadcast on the so-called "French Paradox". Featuring the research work of Bordeaux scientist Serge Renaud, the broadcast dealt with the seemingly paradoxical relationship between the high fat/high dairy diets of French people and the low occurrence of cardiovascular disease among them. The broadcast drew parallels to the American and British diets which also contained high levels of fat and dairy but which featured high incidences of heart disease. One of the theories proposed by Renaud in the broadcast was that moderate consumption of red wine was a risk-reducing factor for the French and that wine could have more positive health benefits yet to be studied. Following the 60 Minutes broadcast, sales of red wine in the United States jumped 44% over previous years.

This changing view of wine can be seen in the evolution of the language used in the U.S. Food and Drug Administration Dietary Guidelines. The 1990 edition of the guidelines contained the blanket statement that "wine has no net health benefit". By 1995, the wording had been changed to allow moderate consumption with meals providing the individual had no other alcohol-related health risk. From a research perspective, scientists began differentiating alcohol consumption among the various classes of beverages – wine, beer, and spirits. This distinction allowed studies to highlight the positive medical benefits of wine apart from the mere presence of alcohol. However wine drinkers tend to share similar lifestyle habits – better diets, regular exercise, non-smoking – that may in themselves be a factor in the supposed positive health benefits compared to drinkers of beer and spirits or those who abstain completely.

Moderate consumption
Nearly all research into the positive medical benefits of wine consumptions make a distinction between moderate consumption, heavy and binge drinking. What constitutes a moderate, healthy level of consumption will vary by individual according to age, gender, genetics, weight and body stature as well as the situation-i.e. is food being consumed as well, are any other drugs currently in the individual's system, etc. Women, in general, tend to absorb alcohol quicker than men due to their lower body water content and difference in levels of stomach enzyme so their moderate levels of consumption tend to be lower than a male of equal age and weight. Some doctors define "moderate consumption" as one 5 USoz glass of wine per day for women and two glasses per day for men.

The view of consuming wine in moderation has a history almost as long as that of wine's role in medicine. The Greek poet Eubulus believed that three bowls (kylix) were the ideal amount of wine to consume. The number of three bowls for moderation is a common theme throughout Greek writing; today the standard 750 mL wine bottle contains roughly the volume of three Kylix cups (250 ml or 8 fl oz each). However, the Kylix cups would have contained a diluted wine, at a 1:2 or 1:3 dilution with water. In his circa 375 BC play Semele or Dionysus, Eubulus has Dionysus say:

Three bowls do I mix for the temperate: one to health, which they empty first, the second to love and pleasure, the third to sleep. When this bowl is drunk up, wise guests go home. The fourth bowl is ours no longer, but belongs to violence; the fifth to uproar, the sixth to drunken revel, the seventh to black eyes, the eighth is the policeman's, the ninth belong to biliousness, and the tenth to madness and hurling the furniture.

Natural phenols and polyphenols
Although red wine contains many other chemicals which may have health benefits, resveratrol has been studied the most. Resveratrol and other such compounds mainly fall in the category of phenolics.

Cinnamates have been shown to have more antioxidant activity when exposed in vitro to the Fenton reaction (catalytic Fe(II) with hydrogen peroxide) than the other natural phenols present in wine.

Resveratrol
Research on potential health effects of resveratrol is in its infancy and the long-term effects of supplementation in humans are not known.

Resveratrol is a stilbenoid phenolic compound found in wine produced in the grape skins and leaves of grape vines. It has received a lot of attention in both the media and medical research community for its potential health benefits.

The production and concentration of resveratrol is not equal among all the varieties of wine grapes. Differences in clones, rootstock, Vitis species as well as climate conditions can affect the production of resveratrol. Also, because resveratrol is part of the defence mechanism in grapevines against attack by fungi or grape disease, the degree of exposure to fungal infection and grape diseases also appear to play a role. The Muscadinia family of vines, which has adapted over time through exposure to North American grape diseases such as phylloxera, has some of the highest concentrations of resveratrol among wine grapes. Among the European Vitis vinifera, grapes derived from the Burgundian Pinot family tend to have substantially higher amounts of resveratrol than grapes derived from the Cabernet family of Bordeaux. Wine regions with cooler, wetter climates that are more prone to grape disease and fungal attacks such as Oregon and New York tend to produce grapes with higher concentrations of resveratrol than warmer, dry climates like California and Australia.

Although red wine and white vine varieties produce similar amounts of resveratrol, red wine contains more than white, since red wines are produced by maceration (soaking the grape skins in the mash). Other winemaking techniques, such as the use of certain strains of yeast during fermentation or lactic acid bacteria during malolactic fermentation, can have an influence on the amount of resveratrol left in the resulting wines. Similarly the use of certain fining agents during the clarification and stabilization of wine can strip the wine of some resveratrol molecules.

The prominence of resveratrol in the news and its association with positive health benefits has encouraged some wineries to highlight it in their marketing. In the early 21st century, the Oregon producer Willamette Valley Vineyards sought approval from the Alcohol and Tobacco Tax and Trade Bureau (TTB) to state on their wine labels the resveratrol levels of their wines which ranged from 19 to 71 micromoles per liter (higher than the average 10 micromoles per liter in most red wines). The TTB gave preliminary approval to the winery, making it the first to use such information on its labels. While resveratrol is the most widely publicized, there are other components in wine that have been the focus of medical research into potential health benefits. These include the compounds catechin and quercetin.

Anthocyanin
Red grapes are high in anthocyanins, which are the source of the color of various fruit, such as red grapes. Anthocyanins have been found to be powerful antioxidants and anti-inﬂammatories, therefore it is possible that one of the mechanisms at work to explain why red wine has been associated with improved health is the significant presence of anthocyanins in red wine. The darker the red wine, the more anthocyanins present. This suggests therefore the darker the red wine the more effective antioxidant and anti-inﬂammatory the red wine.

Bones
Heavy alcohol consumption has been shown to have a damaging effect on the cellular processes that create bone tissue, and long term alcoholic consumption at high levels increases the frequency of fractures. Epidemiological studies (studies done by interviewing subjects and studying their health records) have found a positive association between moderate alcohol consumption and increased bone mineral density (BMD). Most of this research has been conducted with postmenopausal women, but one study in men concluded that moderate consumption of alcohol may also be beneficial to BMD in men.

Cancer
Alcohol is a toxin and damages cells. The International Agency for Research on Cancer of the World Health Organization has classified alcohol as a Group 1 carcinogen. Studies have linked even moderate consumption of alcohol to an increased risk for a variety of cancers including breast, colon, esophageal, and stomach cancer. Focus on wine's positive benefits regarding cancer has centered on the antioxidant properties of resveratrol, found in grapes, with some laboratory results showing a protective quality that inhibit cancerous changes in cells. The research is ongoing with no conclusive results, though some studies suggest that moderate wine consumption may lower the risk for lung, ovarian and prostate cancer. In early 2009, three independent studies published in the medical journal of Gastroenterology suggest that moderate wine consumption may reduce the risk of certain forms of esophageal cancers such as esophageal adenocarcinoma and the precancerous condition Barrett's esophagus. In one study, conducted by Kaiser Permanente in California, respondents who reported drinking no more than 1 glass of wine a day had a 56% decrease in the risk for developing Barrett's esophagus&mdash;a rate lower than that of heavy and non-drinkers. While heavy alcohol consumption has been proven to increase the risk of esophageal cancer, these studies suggest that antioxidants in wine may offer some benefit if consumed in moderation, but there is not a conclusive link. In response to these studies, Dr Prateek Sharma, MD, of the University of Kansas School of Medicine, notes that there may be other links such as people who drink wine lead generally healthier lifestyles by consuming less fats and eating more fruits and vegetables.

Research conducted at the Yale School of Public Health in 2009, suggest that wine may have some protective benefits against some forms of cancer. Women diagnosed with non-Hodgkin's lymphoma were questioned about their alcohol consumption patterns and followed for an 8 to 12-year period. Compared to non-drinkers, women who had been drinking wine for at least 25 years prior were 33% less likely to die over the five-year period following diagnosis and 26% less likely to experience a relapse or develop a secondary cancer during that same five-year period. Of all the women in the study, 75% of those who drank at least 12 glasses of wine over the course of their lifetime were alive after five years compared to 66% of the women who never drank any wine. Women who drank beer and alcohol spirits showed no differences.

While alcohol itself has been linked as increasing the risk of breast cancer in women, a 2008 study by researchers at the University of Nebraska suggest that resveratrol, which is found in grapes, may have some preventative benefits against breast cancer. Prolonged exposure of breast cells to estrogen has long been suspected as to be a major risk factor for breast cancer. This exposure can cause toxic estrogen metabolites to appear that react with DNA in the body to promote the development of tumors. Researchers at the University of Nebraska exposed human breast cells grown in the laboratory to low doses of resveratrol and found that it created numerous positive outcomes. The exposure to resveratrol not only decreased the production of estrogen metabolites but it also increased production of an enzyme that destroys these metabolites. It also appeared to limit interaction between these metabolites and DNA, limiting the promotion of tumor development. The amount of resveratrol used in the study was a low-dose concentration of 10 micromoles per liter. A typical glass of wine has a concentration between 9 and 28 micromoles per liter. However, this laboratory study does not suggest that consuming wine will produce the necessary concentration of resveratrol in the bloodstream to have these cancer fighting properties.

Cardiovascular system
Studies have shown that heavy drinkers put themselves at greater risk for heart disease and developing potentially fatal cardiac arrhythmias. Excessive alcohol consumption can cause higher blood pressure, increase cholesterol levels and weakened heart muscles. For moderate drinkers, medical research indicates moderate wine consumption may lower the mortality rate and risk of heart disease. Studies have shown that moderate wine drinking can improve the balance of low-density lipoprotein (LDL or "bad" cholesterol) to high-density lipoprotein (HDL "good" cholesterol), which has been theorized as to clean up or remove LDL from blocking arteries. The main cause of heart attacks and the pain of angina is the lack of oxygen caused by blood clots and atheromatous plaque build up in the arteries. The alcohol in wine has anticoagulant properties that limits blood clotting by making the platelets in the blood less prone to stick together and reducing the levels of fibrin protein that binds them together.

However these anticoagulant properties of wine only stay in the system for a maximum of 24 hours after consumption. While having a glass of wine the night before may lower the risk of having a heart attack the next day, there is still the potential of long-term effects of alcohol. These anticoagulant properties can also be amplified adversely by binge drinking, with the individual becoming over-anticoagulated and at increase risk of a stroke or heart attack.

Dementia and mental functions
One of the short-term effects of alcohol is impaired mental function, which can cause behavioral changes and memory impairment. Long term effects of heavy drinking can inhibit new brain cell development and increase the risk for developing major depressive disorders. Studies have linked moderate alcohol consumption to lower risk of developing Alzheimer's and dementia though wine's role in this link is not yet fully understood. A 2009 study by Wake Forest University School of Medicine suggest that moderate alcohol consumption may help healthy adults ward off the risks of developing dementia but can accelerate declining memory for those already suffering from cognitive impairment. The reason for the potential positive benefit of moderate consumption is not yet identified and may even be unrelated to the alcohol but rather other shared lifestyle factors of moderate drinkers (such as exercise or diets). If it is the moderate consumption, researchers theorize that it may be alcohol's role in promoting the production of "good cholesterol" which prevents blood platelets from sticking together. Another potential role of alcohol in the body may be in stimulating the release of the chemical acetylcholine which influences brain function and memory.

Diabetes
Research has shown that moderate levels of alcohol consumed with meals does not have a substantial impact on blood sugar levels. A 2005 study presented to the American Diabetes Association suggest that moderate consumption may lower the risk of developing Type 2 diabetes.

Digestive system
The anti-bacterial nature of alcohol has long been associated with soothing stomach irritations and ailments like traveler's diarrhea where it was a preferred treatment to the less palatable bismuth treatments. The risk of infection from the bacterium Helicobacter pylori, strongly associated with causing gastritis and peptic ulcers as well as being closely linked to stomach cancer, appears to lessen with moderate alcohol consumption. A German study conducted in the late 1990s showed that non-drinkers had slightly higher infection rates of Helicobacter pylori than moderate wine and beer drinkers.

Wine's positive effects on the metabolism of cholesterol has been suggested as a link to lower occurrences of gallstones among moderate drinkers since cholesterol is a major component of gallstones.

Headaches
There are several potential causes of so-called "red wine headaches", including histamines/tyramines and the breakdown of some phenolic compounds in wine that carry the chemical messenger for serotonin. One culprit that is regularly dismissed by allergists as an unlikely cause of red wine headaches is sulfites which are used as a preservative in wine. Wine, like other alcoholic beverages, is a diuretic which promotes dehydration that can lead to headaches (such as the case often experienced with hangovers). In 2006, researchers from the University of California, Davis announced finding from genetic mapping that amino acids in wine that have been slightly modified by the fermentation process may be the cause of wine related headaches. The research suggest changes in fermentation techniques may help alleviate the risk for wine drinkers sensitive to these amino acids.

Vision
The anti-oxidant and anticoagulant properties of wine may have a positive benefit in slowing the effects of macular degeneration that causes vision to decline as people age. An American study from the late 1990s showed that vision of moderate wine drinkers suffered less macular degeneration than non-drinkers

Weight management
Arthur Agatston, co-creator of the South Beach diet believes that wine can offer some positive benefit for weight management if it is consumed with food. Alcohol can stimulate the appetite so it is better to drink it with food. When alcohol is mixed with food, it can slow the stomach's emptying time and potentially decrease the amount of food consumed at the meal.

Compared to many beers and non-diet sodas, a serving of wine has a moderate amount of calories. A standard 5 oz serving of red wine (based on an average alcohol content of 13%) contains approximately 106 calories and 2.51 g of carbohydrates. A similar serving of white wine contains approximately 100 calories and 1.18g of carbohydrates.

Psychological and social
Danish epidemiological studies suggest that a number of psychological health benefits are associated with drinking wine. In a study testing this idea, Mortensen et al. (2001) measured socioeconomic status, education, IQ, personality, psychiatric symptoms, and health related behaviors, which included alcohol consumption. The analysis was then broken down into groups of those who drank beer, those who drank wine, and then those who did and did not drink at all. The results showed that for both men and women drinking wine was related to higher parental social status, parental education and the social status of the subjects. When the subjects were given an IQ test, wine drinkers consistently scored higher IQs than their counterpart beer drinkers. The average difference of IQ between wine and beer drinkers was 18 points. In regards to psychological functioning, personality, and other health-related behaviors, the study found wine drinkers to operate at optimal levels while beer drinkers performed below optimal levels. As these social and psychological factors also correlate with health outcomes, they represent a plausible explanation for at least some of the apparent health benefits of wine.

Heavy metals in wine controversy
In 2008, researchers from Kingston University in London discovered red wine to contain high levels of toxic metals relative to other beverages in the sample. Although the metal ions, which included chromium, copper, iron, manganese, nickel, vanadium and zinc, were also present in other plant-based beverages, the sample wine tested significantly higher for all metal ions, especially vanadium. Risk assessment was calculated using "target hazard quotients" (THQ), a method of quantifying health concerns associated with lifetime exposure to chemical pollutants. Developed by the Environmental Protection Agency in the US and used mainly to examine seafood, a THQ of less than 1 represents no concern while, for example, mercury levels in fish calculated to have THQs of between 1 and 5 would represent cause for concern.

The researchers stressed that a single glass of wine would not lead to metal poisoning, pointing out that their THQ calculations were based on the average person drinking one-third of a bottle of wine (250 ml) every day between the ages of 18 and 80. However the "combined THQ values" for metal ions in the red wine they analyzed were reported to be as high as 125. A subsequent study by the same university using a meta analysis of data based on wine samples from a selection of mostly European countries found equally high levels of vanadium in many red wines, showing combined THQ values in the range of 50 to 200, with some as high as 350.

The findings sparked immediate controversy due to several issues: the study's reliance on secondary data; the assumption that all wines contributing to that data were representative of the countries stated; and the grouping together of poorly understood high-concentration ions, such as vanadium, with relatively low-level, common ions such as copper and manganese. While some publications printed lists of countries showing the "worst offenders" and reported that wine from other countries did not pose a health risk, others pointed out that the lack of identifiable wines and grape varieties, specific producers or even wine regions, provided only misleading generalizations that should not be relied upon in choosing wines.

In a news bulletin following the widespread reporting of the findings, the UK's National Health Service (NHS) were also concerned that "the way the researchers added together hazards from different metals to produce a final score for individual wines may not be particularly meaningful". Commentators in the US questioned the relevance of seafood-based THQ assessments to agricultural produce, with the TTB, responsible for testing imports for metal ion contamination, have not detected an increased risk. George Solas, quality assessor for the Canadian Liquor Control Board of Ontario (LCBO) claimed that the levels of heavy metal contamination reported were within the permitted levels for drinking water in tested reservoirs.

Whereas the NHS also described calls for improved wine labeling as an "extreme response" to research which provided "few solid answers", they acknowledged the authors call for further research to investigate wine production, including the influence that grape variety, soil type, geographical region, insecticides, containment vessels and seasonal variations may have on metal ion uptake.