We begin with a review of some of the published studies regarding the health benefits from wine and other alcoholic beverages. The following is taken mostly from the writings of Elisabeth Holmgren, director of the Department of Research and Education at the Wine Institute. Although she represents the wine industry, her writings seem to be relatively even handed. Nothing that follows is meant to obscure the fact that prolonged excessive alcohol consumption is detrimental to one’s health. Joel’s comments are in brackets [JM].
Wine’s Role in the “French Paradox” Receives Confirmation
A new study by original “French Paradox” researcher Serge Renaud offers more evidence that moderate wine consumption is associated with a significant reduction in all-cause mortality, cardiovascular disease and cancer among men. The findings (Epidemiology, March, 1998) were based on a large cohort study [JM - cohort studies are epidemiological studies that use individuals having a statistical element in common, such as race, gender, age, etc., as opposed to a random selection of individuals. As such, the results cannot always be projected to the population as a whole.] of middle aged men in eastern France. Daily, moderate drinkers who consumed mostly wine were compared to non-drinkers and heavy drinkers.
Renaud and colleagues from the University of Bordeaux found that moderate wine consumption (2-3 glasses a day) was associated with a 30% reduction in the death rate from all causes; a 35% percent reduction in death rates from cardiovascular disease; and an 18-24% reduction in death rates from cancer. “The results of the present study,” the researchers write, “appear to confirm the speculation that the so-called French Paradox is due, at least in part, to the regular consumption of wine. [JM - The French Paradox, of 60 minutes fame, is the observation that, although the French and Americans have similar high fat diets, the French have a much lower incidence of cardiovascular disease. Speculation was that this is due to the protective effects of wine consumption, since the French drink much more wine than we do. Of course, there are many other possible explanations.]
How Wine Works: Emerging Research on Mealtime Alcohol Consumption
It is known that alcohol consumption reduces the risk of coronary heart disease and overall mortality. [JM - This statement is a bit strong. Statistical studies show a relationship between two variables (here, moderate alcohol consumption and reduced incidence of heart disease), but they do not establish a cause and effect relationship - “proof” that one causes the other. The recent wealth of data should give us more confidence in a cause and effect relationship, but we are not nearly to the point of “proof.” It took decades and hundreds of studies before the Surgeon General was willing to declare that smoking causes cancer.] But it has been less clear just how alcohol works to protect the body against heart disease and death.
A new study from researchers at the University Hospital of Zurich, Switzerland. identifies a mechanism for how alcohol favorably effects arterial muscle cells. According to Wilhelm Vetter, M.D., and colleagues, alcohol, when consumed around mealtime, reduces the proliferation of smooth muscle cells (SMC) within the arteries. SMC growth is a key element in the develop-ment of atherosclerosis, which commonly leads to heart attacks and strokes.
The study found that the ingestion of alcohol. equivalent to two glasses of wine or three beers, with a high-fat meal resulted in a 20% decrease in the growth of arterial muscle cells. Researchers suggest these results could have a profound effect on heart disease “considering the amount of time humans spend in the postprandial state during their lifetimes.”
Other mechanisms may be at work. Several researchers have suggested that the apparent health benefits of wine ingested at mealtime may be due to the ability of alcohol and other phenolic compounds in wine to counter adverse effects of fatty foods during the critical digestive phase. Renaud has written of the positive effect of wine during meals on platelet aggregation , finding that wine “consumed with meals is absorbed more slowly, and thus has a prolonged effect on blood platelets at a time when they are under the influence of alimentary lipids known to increase their reactivity.”
An Israeli study by Fuhrman et al, published in the American Journal of Clinical Nutrition, found that drinking red wine with meals resulted in a 20% reduction in the LDL (“bad”) cholesterol oxidation. A Dutch study, published in the British Medical Journal, found that alcohol consumed with a meal may prevent blood clotting triggered by fat.
Women Wine Drinkers Have Fewer Kidney Stones
A new study from Harvard University researcher Gary Curhan and colleagues, using more than 81,000 women participants drawn from the Nurses’ Health Study, found that an increase in fluid intake significantly reduces risk for kidney stones and that risk reduction was greatest for wine compared with other beverages. Out of 17 beverages, including tea, coffee, fruit juices, milk and water, wine was associated with the highest reduction in risk - 59%.
Researchers noted: “Intakes of caffeinated and decaffeinated coffee, tea and wine were associated with decreased risk.” Curhan and colleagues reported similar results for men and kidney stones in 1996. Wine consumption was associated with highest risk reduction - 39%.
Moderate wine consumption cuts stroke risk
The moderate consumption of wine (but not beer or spirits) is associated with a reduced risk of stroke, according to a new report. The authors believe wine’s protective effects may be linked to disease-fighting compounds other than alcohol. “Intake of wine is associated with lower risk of stroke,” concludes a 16-year Danish study led by Dr. Thomas Truelsen of Copen-hagen University Hospital (Journal of the American Heart Association, December, 1998).
Previous studies have suggested that moderate wine consumption (a glass a day, for example) may provide cardiovascular benefit. This phenomena is exemplified by what the Danish team call the ‘French paradox’ - “a low incidence of cardiovascular disease in the (wine-drinking) French population despite an unfavorable exposure to known cardiovascular factors (such as smoking).” Investigating further, the authors tracked the stroke incidence of over 13,300 Danes for 16 years.
They report that, compared with abstainers, individuals who said they drank wine on a monthly, weekly, or daily basis had a 16%, 34%, and 32% reduced risk of stroke, respectively. The researchers found “no association between intake of beer or spirits on risk of stroke.”
These findings suggest that other compounds in wine besides alcohol may have a positive impact on cardiovascular health. “Wine contains flavonoids and tannins,” the authors explain, “which are components presumed to prevent cardiovascular disease.” They speculate that drinking patterns specific to wine lovers may also influence cardiovascular health. Wine is more commonly consumed at mealtimes than either beer or hard liquor, and “these differences in ‘timing’ may be important,” according to the researchers. One recent study concluded that mealtime alcohol consumption reduced unhealthy alterations in blood composition that can occur after eating.
In a press release, the American Heart Association “does not recommend that individuals start drinking to reduce their risk of heart disease and stroke.” Experts point out that excessive drinking can actually raise the likelihood of cardiovascular disease, heart attack, and stroke.
Regular, Moderate Alcohol Consumption Protects Against Atherosclerosis
New Data from the Bruneck Study (Italy) was reported by Australian and Italian researchers in the May 1998 issue of Stroke. They conclude that light to moderate alcohol consumers faced a lower risk of atherosclerosis (early atherogenesis) than either abstainers or heavy drinkers. Arteriosclerosis, the gradual build-up of fatty deposits in the arteries, is the leading contributor to coronary heart disease and fatal heart attacks.
Notably, alcohol consumption during meals offered advantages. “Alcohol ingestion during meals tended to offer more protection, probably due to a delayed absorption and prolonged mode of action at a time when platelet reactivity increases under the influence of alimentary lipids,” explained the researchers, led by Innsbruck University’s Stefan Kiechl, M.D.
Cohort Studies From Around the World Link Moderation to Longevity
In recent years dozens of cohort studies from all over the world have associated moderate alcohol consumption with reduced risk for cardiovascular disease, decreased overall mortality rates and other potentially improved health conditions. This growing worldwide research consensus has resulted in certain changes in the world view of alcohol during just the last few years. In a significant departure form the past, major public health organizations and governments around the world now officially recognize that moderation can be part of a healthful diet for those who choose to drink. The World Health Organization, the United States government, the United Kingdom’s government and the American Heart Association are among the health policy leaders that recently have issued balanced alcohol statements expressing caution in terms of alcohol abuse, but highlighting scientific findings that associate cardiovascular benefits with moderate consumption.
In varying degrees, wine, beer and spirits have been shown to confer certain health advantages for those who consume in moderation. The most recent review study on the subject of alcohol and longevity was by esteemed British epidemiologist Richard Doll, M.D. In the British Medical Journal, Doll concluded, “The consumption of small and moderate amounts of alcohol reduces mortality from vascular disease by about a third.” In his review, Doll looked over three dozen studies published over the last decade. We will discuss some of these cohort studies from around the world which are highlighted in the table below.
Alcohol and Wine’s Effects on Mortality - Findings From Around the World
United States Europe Asia/Australia
Framingham Heart Study (MA) Seven Countries Study Japanese Physicians
Kaiser Permanente (CA) British Regional Heart Study Busselton Study (Austral)
Nurses Health Study (MA) British Doctors Study Dubbo Study (Austral)
Physicians Health Study (MA) Copenhagen City Heart Study New Zealand Cohort
Health Professionals (MA) MONICA (WHO) Shanghai China Cohort
NHANES (USA) Italian Rural Cohorts Study
Honolulu Heart Study (HI)
Well-Established Cardiovascular Benefits of Moderation
As early as 1980, the Honolulu Heart Study reported that moderate alcohol consumption was associated with a 50% reduction in the rate of coronary heart disease. Dozens of studies around the world have since confirmed this for both men and women. In the 1990’s, large-scale studies including the Health Professionals Follow-Up Study (over 44,000 men) and the Nurses’ Health Study of over 85,000 women have convincingly demonstrated reduced risks for heart disease. The data are so clear on this issue that leading Harvard researchers included moderate alcohol consumption as one of the best ways to cut heart attack risk. In 1996, they credited “one or two drinks of beer, wine, or liquor per day” to “a reduction in risk of 20-40%.
The latest research has also found associations between moderation and other cardiovascular diseases. In early 1997, data was published showing that moderate alcohol con-sumers reduced their risk for stroke, angina pectoris (a painful precursor of heart attacks) and for peripheral artery disease, a condition in which internal blood clots form in the extremities.
It was Dr. Arthur Klatsky of Kaiser Permanente Hospital in California who first noted that the association between consumption and heart disease resembled a “U” with moderate con-sumers at the lowest risk in the curve, and abstainers and abusers at higher risk. This U-shaped relationship between alcohol intake and disease continues to be seen for both cardiovascular and overall mortality studies. Moderate consumption appears to be most advantageous.
Moderation and Reduced All-Cause Mortality
Some of the most respected population studies find that consuming wine, beer or spirits in moderation has been associated with an increased life expectancy. Researchers report that although substantial decreases in mortality risk for moderate drinkers can be attributed to reduced risk of heart disease, this factor alone does not entirely account for their favorable mortality profile. Moderate drinkers compared to abstainers, both male and female, appear to be at lower risk for all causes of death, including cancer and other chronic diseases, while heavy drinkers increase their mortality risk. This U-shaped relationship was seen in the Honolulu Heart study and subsequently in an American Cancer Society Study which found that subjects who consumed moderate amounts of alcohol (less than 3 drinks per day) were less likely to die during the research period than either abstainers or heavy drinkers. Several studies with similar findings have led the American Heart Association to state in 1996, “The lowest mortality occurs in those who consume one or two drinks per day.”
A 13-year follow-up of a British Physician’s Study found that the overall death rate for 12,000 male doctors in middle or old age who had an average of one to two drinks per day of wine, beer, or spirits was at least 1/6 lower than that for abstainers. Investigators for the Danish government’s Copenhagen City Heart Study similarly analyzed 10-12 years of follow up data on 7234 women and 6051 men aged 30 to 79. A U-shaped curve emerged: consumers of 1-6 drinks per week had the lowest risk for all causes of mortality. A 1997 Shanghai Cohort Study, the first major Chinese study, examined 18,000 men in Shanghai and found a 19% lower mortality rate for all causes in moderate drinkers.
The Nurses’ Health Study (1995) found a reduced overall mortality rate for light-to-moderate drinkers among 85,000 women. They concluded, “For women as a group, light to moderate alcohol consumption offers significant survival advantages. It was associated with a decreased risk of death from cardiovascular disease; heavier drinking was associated with an increased risk of death from other causes, particularly breast cancer and cirrhosis.” Benefits were most pronounced for women with risk factors for heart disease and those 50 years and older.
Other Harvard University cohort studies, the Framingham Heart Study as well as the Kaiser Permanente Study confirm overall mortality benefits for moderate drinkers. The National Health and Nutrition Examination Survey (NHANES), the largest government survey of Americans’ health and lifestyle habits, reported that for white males, “Moderate drinking increases the time until death from any cause by about 3 percent.”
At the same time, scientists point out that more research is needed to provide a true risk/benefit analysis for different gender and age groups that considers not only coronary heart disease and overall mortality, but also various types of cancer. In particular, some studies find a link between alcohol consumption and breast cancer in women. However, most researchers feel that the cardiovascular benefits of moderate alcohol consumption far outweigh the breast cancer risks (Cardiovascular disease is very common; breast cancer is rare in comparison).
Wine Phenolics and Disease Prevention
While some researchers believe that all alcoholic beverages provide equal benefit, several scientists believe wine offers benefits in addition to its ethyl alcohol component. The beverage-specific data from the ongoing Copenhagen City Heart Study reported that wine drinkers were least likely to die from any cause during the 12-year study period. “Our finding, that only wine drinking clearly reduces both the risk of dying from cardiovascular and cerebrovascular disease and the risk of dying from other causes”, write researcher Morton Gronbaek and colleagues, “suggests that other more broadly acting factors in wine may be present.”
Research programs on other factors in wine has resulted in several studies in the past few years on the antioxidant and protective effects of wine compounds. Several phenolic compounds in wine (such as quercetin, epicatechin and resveratrol) inhibit platelet aggregation and act as antioxidants to prevent the breakdown of LDL cholesterol into atherosclerotic plaque. One in vitro study even found that these compounds were more effective than vitamin E in inhibiting LDL oxidation. Since 1991 over three dozen studies have provided preliminary evidence that wine phenolics have positive health effects. However, as most of this research comes from animal studies, it has not yet been demonstrated that this is applicable to humans.
Key recent cohort studies (Harvard’s Physician’s Health Study and the American Cancer Society’s Cancer Prevention Study II) found lower mortality profiles for moderate drinkers. The ACS study was the largest on alcohol consumption to date, with nearly half a million subjects, finding all-cause mortality risk to be reduced by approximately 20% for both men and women who consumed one drink per day. Several published reviews have pointed out that higher levels of alcohol consumption can be detrimental to health in many ways. However, as Finnish researcher Kari Poikolainen wrote in a 1995 review in the Journal of Clinical Epidemiology, “The lowest risk of death seems to be at the average intake level of one drink per day.”
Key studies throughout the 1990’s (see Table last month) associate approx. one drink per day with increased longevity. In each study, all-cause mortality rates for moderate drinking men and women, in diverse populations such as the US, China and Australia, are significantly lower than rates for non-drinkers. Based on a decade of research findings, Richard Doll, M.D. (in the British Medical Journal) calls the evidence for alcohol’s beneficial effect “now massive. People should told the facts. These still need to be defined in detail, but in broad outline they are quite clear: In middle and old age, some amount of alcohol within the range of one to four drinks each day reduces the risk of premature death, irrespective of the medium in which it is taken.”
The U.S. Dietary Guidelines advises moderation, which is defined as no more than two drinks per day for men and no more than one drink per day for women. Forthcoming research will continue to clarify the effects of moderate wine and alcohol consumption in healthy diets and balanced lifestyles. It is hoped that these findings will be reflected in worldwide nutrition policies like the year 2000 Dietary Guidelines for Americans.
Drinking Wine May Lower Risk for Upper Digestive Tract Cancer
Many research studies have associated alcohol consumption with increased risk of upper digestive tract cancers. But Morton Gronbaek and colleagues at the Institute for Preventive Medicine in Copenhagen, Denmark, report just the opposite. They speculate that previous studies did not analyze data for specific types of beverages and/or did not distinguish between use and abuse. Although they acknowledge that their analysis may not be perfect, the Danish researchers tracked the 13-year incidence of mouth, throat and esophageal cancers among 28,000 Danes. They report that heavy drinkers experienced a 12-fold increase in upper digestive cancers compared with abstainers. But among moderate drinkers, those who consumed at least 30% of their alcohol intake in the form of wine were at slightly lower risk than non-drinkers for these cancers. “A moderate intake of wine probably does not increase the risk of upper digestive tract cancer.” They speculate that compounds found in wine, such as resveratrol, may exert powerful anticarcinogenic effects that protect against any cancer-causing effects of alcohol. “Wine contains several components with possible anticarcinogenic effects - these may exert their action locally in parallel with the possible effect of ethanol.”
New Research Developments of the Antioxidant Front
The Italian National Institute of Nutrition (Rome) found that phenolic compounds in wine are absorbed in the gastrointestinal tract and “might be directly involved in the in vivo antioxi-dant defenses.” This study clearly associated non-alcoholic components in wine with increased plasma antioxidant capacity, which may lead to a reduced risk in coronary heart disease.
A team of researchers from New York, Japan and the University of Illinois reported prelim-inary evidence that resveratrol (a compound found primarily in grapes and wine) may inhibit cancer growth in humans.
Moderate Drinkers’ Benefits Begin in Early Adulthood
A new study from the UK, published in The Lancet, has found that among young adults, moderate drinkers are at a reduced risk of psychological distress, poor general health and long-term illness compared to abstainers and heavy drinkers. Dr. Chris Powers and associates studied 9,605 men and women at age 23 with a follow-up at 33. They found that men drinking between 11-35 units of alcohol and women drinking between 6-20 units of alcohol per week experienced fewer health-related problems than nondrinkers and heavy drinkers. One unit of alcohol was the equivalent to a half pint of beer, one measure of spirits or one glass of wine.
Dr. Powers is from the Institute of Child Health (London) and the co-authors are from the Australian National University (Canberra). They hope to continue the research with the same subjects in order to see how they progress with age. This is one of the first studies to look at the effects of alcohol consumption in early adulthood and it’s long-term effects on health.
The information in this article is for educational purposes only. Wine should be enjoyed in a responsible manner as part of a well balanced lifestyle by healthy adults who choose to drink. “If you drink alcoholic beverages, do so in moderation, with meals, and when consumption does not put you or others at risk” ~ Advice for Today, 1995 U.S. Dietary Guidelines for Americans. Meanwhile, the research on the health benefits of wine continues!
Updates on Wine and Health
Wine linked with lower lung cancer risk
NEW YORK, Mar 01, 2000 (Reuters Health) -- Male wine drinkers may have a lower risk of lung cancer than those who drink beer or spirits. Dr. Eva Prescott and colleagues at Copenhagen University Hospital examined data from three Danish studies involving more than 28,000 adults. Overall, they found no association between low to moderate alcohol intake and lung cancer risk. When the analysis was limited to men, they observed that those who drank wine had a lower risk of lung cancer than those who did not drink wine. But the data also suggested an increased risk of lung cancer in men who drank beer or spirits. For example, men who reported drinking 1 to 13 glasses of wine per week had a 22% lower risk of lung cancer compared with drinkers of other types of alcohol. Men who consumed more than 13 glasses of wine per week had a 56% lower risk than other alcohol drinkers. The researchers suggest that the seemingly protective effect “may be related to the antioxidant properties of wine, and deserves further attention.” SOURCE: American Journal of Epidemiology 1999;149:463-470.
Light-to-moderate alcohol intake may prevent stroke
NEW YORK, Nov 17, 1999 (Reuters Health) -- People who consume as little as one alcoholic drink per day significantly reduce their risk of stroke, but drinking more does not increase the benefit, results of a study suggest. Previous studies have shown that “drinking moderate amounts of alcohol may have protective effects against subtypes of stroke,” according to Dr. Klaus Berger, from Brigham and Women's Hospital in Boston, Massachusetts, and colleagues.
The researchers analyzed the medical records of more than 22,000 male doctors aged 40 - 84. Over 12 years, 679 men experienced first strokes. Most of the strokes were caused by interruptions of the brain’s blood supply (ischemic strokes), while fewer than 15% were caused by brain bleeding (hemorrhagic strokes). Compared with other participants, the group of men who consumed at least one drink per week had a 21% lower risk of having any type of stroke.
The same group had a 23% lower risk of ischemic stroke, the scientists calculated. Drinking had neither a positive nor a negative effect on the risk of hemorrhagic stroke. After Berger and his colleagues accounted for other risk factors, they found that “the largest risk reductions were found among the men who had one to four drinks per week.” Blood pressure and exercise affected the impact of drinking on stroke risk, according to the investigators. Alcohol consumption benefited men whose blood pressure was 140 or higher or who exercised at least once a week. The authors conclude that “light-to-moderate consumption of alcohol (one to seven drinks per week) reduced the risks of total stroke and ischemic stroke.” SOURCE: The New England Journal of Medicine 1999;341:1557-1564, 1605-1606.
Red wine without the alcohol good for the heart
NEW YORK, Jan 03, 2000 (Reuters Health) -- It may not please wine connoisseurs, but red wine without the alcohol is also good for the heart, researchers report. Dr. Jennifer R.C. Bell and colleagues at the University of California, Davis, report the results of their study, in which they took a 1996 Cabernet Sauvignon and removed the alcohol. They then asked 5 men and 4 women -- all healthy -- to drink about a 1/2 cup of the wine, with water added on one day and water and ethanol added on the other. The investigators measured levels of the flavonoid “(+)-catechin” -- the wine component credited with heart benefits -- after consumption.
The researchers collected blood at baseline and then 30 minutes, 1, 2 3, 4 and 8 hours after consumption. They found that the half-life of (+)-catechin was significantly shorter (3.17 hours) when subjects drank alcoholic red wine than when they drank the dealcoholized version (4.08 hours). Bell and colleagues report that increases in total (+)-catechin in plasma were similar after ingestion of alcoholic and nonalcoholic red wine and that gender had no effect.
But moderate amounts of alcohol also make a contribution to heart health. Previous research shows that alcohol by itself increases concentration of HDL -- “the good cholesterol” -- in the blood, the researchers note. “The results (of this study)... suggest that red wine provides two independent factors capable of contributing to vascular health when consumed in moderation,” the investigators write, namely the HDL-boosting effects of alcohol and the increase of flavonoids in the blood. SOURCE: American Journal of Clinical Nutrition 2000;71:103-108.
One drink is good, more than two isn't
NEW YORK, Jan 03, 2000 (Reuters Health) -- Consumption of one alcoholic drink per day appears to reduce the risk of heart disease in middle-aged men, but more than two drinks each day may offset these benefits by increasing the risk of some cancers, researchers report. “Our observational research shows that there seems to be benefit of light to moderate alcohol consumption,” Dr. J. Michael Gaziano told Reuters Health. “However, people shouldn’t drink instead of doing other preventive activities such as stopping smoking, controlling cholesterol and exercising.” And the data from US physicians participating in the Physicians’ Health Study show that excess consumption will cancel the benefits of moderate consumption, by increasing the risk of some of the less common cancers.
Any recommendation on alcohol consumption should be individualized through discussions with a physician, according to Gaziano of the Veterans Affairs Medical Center and Brigham and Women's Hospital in Boston, Massachusetts. People with liver disease or a history of alcohol abuse should not drink at all, while those with diabetes and hypertension may partake in light alcohol consumption, Gaziano said.
Gaziano and colleagues analyzed self-reported alcohol consumption of 89,299 male physicians between the ages of 40 and 84 years with no prior medical history of heart attack, stroke, cancer or liver disease. Their findings are reported in the January issue of the Journal of the American College of Cardiology. After an average of more than 5 years of follow-up the data revealed that, “light to moderate drinking -- perhaps one per day -- shows benefits in reducing risk of heart disease with no increased risk of cancer,” Gaziano said. SOURCE: Journal of the American College of Cardiology 2000;35:96-105.
Moderate drinking lowers diabetes risk in men
NEW YORK, Jan 06, 2000 (Reuters Health) -- Men who are ‘moderate’ drinkers -- between 5 to 10 drinks per week -- have a lower risk for adult-onset diabetes than either abstainers or heavy drinkers, researchers report. “Men with a high alcohol intake may be able to reduce their risk of developing type 2 diabetes if they drink less,” report Dr. Ming Wei and colleagues at the Cooper Institute in Dallas, Texas.
As reported previously by Reuters Health, numerous studies have suggested that having a drink or two per day appears to have a protective effect against cardiovascular disease. In their study, Wei’s team examined rates of type 2 diabetes -- the adult-onset form of the disease affecting 95% of all diabetics -- in over 8,600 Texan men. They found that diabetes risks were lowest in men who drank between 5 and 10 drinks per week, compared with either abstain-ers/infrequent drinkers (0 to 5 drinks per week) or heavy drinkers (10 to 22 drinks or above). In fact, infrequent or heavy drinkers faced twice the risk of type 2 diabetes of moderate drinkers!
Wei told Reuters Health that, according to previous studies, moderate drinking “reduces insulin resistance,” while heavy alcohol consumption “increases insulin resistance.” Insulin resistance -- in which the body gradually stops responding to the sugar hoarding effect of the hormone insulin -- is thought to precede full-blown type 2 diabetes. Based on their findings, the authors estimate that “24% of the incident cases of diabetes in (adult men) might be attributable to high alcohol intake.” While they do not recommend that abstainers take up drinking to lower their diabetes risk, they do urge that heavy drinkers cut back in order to lower their risk. SOURCE: Diabetes Care 2000;23:18-22
Study Suggests Why Red Wine Does a Heart Good
By Suzanne Rostler
NEW YORK (Reuters Health) - UK researchers have zeroed in on compounds in red wine that battle a protein linked to heart disease--a finding that provides clues to why the French have relatively low rates of heart disease despite a national diet rich in creamy cheese and buttery desserts. The investigators found that polyphenols--compounds in grape skins and present in red wine--decrease the production of a protein that causes blood vessels to constrict and reduces the flow of oxygen to the heart. The protein, endothelin-1, is believed to play a key role in the development of heart disease, explain Dr. Roger Corder and colleagues from Queen Mary University of London.
Their findings support the results of earlier studies showing that a moderate intake of red wine may lower the risk of heart disease. But while these studies focused on the antioxidant properties of polyphenols--their ability to quench disease-causing free radicals in the body--the results of the new study suggest a new mechanism by which red wine might bring benefits. According to the report in the December 20/27th issue of Nature, red wine polyphenols inhibit protein tyrosine kinases, a group of enzymes that play a key role in cell regulation. Compounds that inhibit these enzymes have been shown to suppress endothelin production, Corder told Reuters Health.
“We believe that red wines contain specific polyphenols that inhibit protein tyrosine kinases, and that this effect leads to suppression of endothelin synthesis,” he said in an interview. “The effects we describe are completely unrelated to any antioxidant properties of polyphenols.'”
White wine is made without the use of grape skins, while red wine is made by fermenting the juice from grapes along with the skins. Grape skin provides red wine with its color, and also contains the highest concentration of polyphenols. Other alcoholic beverages do not contain these compounds. “Consumption of one to two glasses of red wine per day with food might be considered part of a diet to reduce heart disease, provided there are no health grounds for avoiding alcohol, and that the person is not going to drive or operate equipment,” Corder said. The study findings are based on experiments with cow artery cells treated with alcohol-free extracts of various red, white and rose wines. The researchers also tried an extract of red grape juice, which inhibited endothelin production, but much less so than red wine did.
SOURCE: Nature 2001;414:863-864.
Updates on Wine, Alcohol, and Health
Moderate Drinking May Cut Women's Risk of Diabetes
NEW YORK (Reuters Health) - New research suggests that drinking moderate amounts of alcohol may help prevent healthy postmenopausal women from developing diabetes as well as heart disease. According to the report, women who consumed one to two drinks a day were better able to respond to insulin, a hormone that helps cells use sugar for energy. These women also had lower levels of insulin in their blood. High blood levels of insulin, as well as decreased insulin sensitivity, are risk factors for heart disease and type 2 diabetes.
In the study, 51 healthy, postmenopausal women rotated among three 8-week treatment periods in which they consumed either no alcohol, one drink a day, or two drinks daily, in addition to a diet to maintain their body weight. Blood samples drawn from the women revealed that insulin levels were nearly 20% lower after consuming two drinks compared to women consuming no alcohol. Levels of triglycerides, a type of fat associated with increased risk of heart disease, were about 10% lower in the two-drink-a-day group compared with the no-alcohol group. Insulin sensitivity rose by roughly 7% after two drinks. There was no effect on blood glucose.
The researchers attributed the findings to the effects of alcohol, but note that other compounds in red wine may provide additional protection. Whatever the beneficial component in alcohol may be, the findings are consistent with previous reports that have observed improved insulin sensitivity among nondiabetic adults who drink moderately.
SOURCE: The Journal of the American Medical Association 2002;287:2559 (5/15/02)
Moderate Drinking May Cut Dementia Risk -Study
NEW YORK (Reuters Health) - Moderate drinking may reduce an older person’s risk of developing dementia, a new study suggests. Researchers in the Netherlands found that among the 5,400 older adults they studied, those who had up to three drinks a day were less likely than non-drinkers to develop any type of dementia, including Alzheimer’s disease. And it did not matter whether the alcohol was wine, beer, liquor, or a fortified wine such as sherry. However, the relatively few who said they had four or more drinks in a day saw no such protective effect.
Past research has suggested that a drink or two a day might help ward off the mental decline associated with age. Since evidence also shows light-to-moderate drinking may benefit the heart, investigators speculated that alcohol might similarly help maintain blood flow to the brain by reducing clotting or improving cholesterol levels. Another possibility is that alcohol directly affects mental functioning through the release of the neurotransmitter acetylcholine. Substantial evidence indicates that ACH affects learning and memory. Low levels of alcohol stimulate the chemical’s release in humans, while higher alcohol levels inhibit it in studies with rats.
In the study, mentally healthy men and women aged 55 and older were followed for an average of 6 years. During the study, 197 participants developed dementia, most often Alzheimer's disease. Those who had said they drank one to three alcoholic beverages a day were 42% less likely to develop any type of dementia, regardless of the other health factors. They were 70% less likely than non-drinkers to be diagnosed with vascular dementia, an impairment caused by significant reductions in the brain’s blood supply.
In addition, a couple of drinks per day showed a protective effect among people who carried the gene variant ApoE4, which is associated with an increased Alzheimer’s risk. The researchers speculated that alcohol, possibly through improving cholesterol levels, might moderate dementia risk among ApoE4 carriers.
SOURCE: The Lancet 2002;359:281-286 (1/26/02)
Red Wine May Keep Prostate Cancer Cells in Check
NEW YORK (Reuters Health) - Compounds in red wine may keep prostate cancer cells from proliferating, results of a preliminary laboratory study suggest. Researchers from Spain found five different polyphenols, antioxidants found in red wine, tea, and certain fruits and vegetables, inhibited the growth of prostate cancer cells in a test tube and encouraged cancer cells to “commit suicide,” a natural process called apoptosis.
The findings, if confirmed by larger studies, may help to explain the higher rates of prostate cancer in the US and non-Mediterranean European countries. The rate of prostate cancer in Mediterranean countries, where intake of red wine and other polyphenol-containing foods is high, tends to be lower. The Mediterranean diet is considered to be protective against the endocrine cancers (including prostate cancer), and features a low animal-fat and meat content, with a high intake of fresh fruit, vegetables, pasta, and wine.
The study examined the effect of five polyphenols found in red wine--gallic acid, tannic acid, morin, quercetin and rutin--on prostate cancer cells. The researchers added varying amounts of these compounds to a dish containing prostate cancer cells. All five compounds inhibited cell proliferation and promoted apoptosis. The results point to a need for studies investigating the effects of these compounds in humans with the potential goal of developing recommendations for use in cancer prevention. Prostate cancer is the second-deadliest form of cancer for US men, after lung cancer, according to the American Cancer Society.
SOURCE: BJU International 2002;89:950-954.
Light Drinking May Help Keep Leg Arteries Clear
NEW YORK (Reuters Health) - Moderate drinkers may be less likely to develop blockages in the arteries that supply blood to the legs. In a study of almost 4,000 people over 55, Dutch researchers found that all women and non-smoking men who reported having 1 or 2 drinks a day were less likely than nondrinkers to have peripheral arterial disease (PAD). These results complement previous research that suggests light drinking can reduce cardiovascular disease risk.
The strongest effect was noted in non-smoking women who were 59% less likely to have PAD than teetotalers. PAD occurs when arteries in the legs become blocked by a buildup of fatty material, a process known as atherosclerosis. PAD can lead to leg cramps when walking. Atherosclerosis in general can bring on stroke and heart attacks. Alcohol may slow atherosclerosis by inhibiting the oxidation of cholesterol, which prevents it from accumulating inside arteries. Since atherosclerosis can lead to other cardiovascular problems, reducing this process may be the means by which light drinking promotes heart and blood vessel health in general. The benefits of alcohol may stem primarily from red wine. This could explain the stronger effect seen in women, since women tended to choose wine, whereas almost half of men liked beer best.
SOURCE: American Journal of Epidemiology 2002;155:332-338.
Alcohol May Benefit Heart Attack Patients
NEW YORK (Reuters Health) - Moderate drinking has been linked with a lower risk of a heart attack. Two new studies show that a drink a day may promote survival in patients after a heart attack, as well as help the elderly avoid heart failure. The researchers of both reports found that any type of alcohol had potentially healthy effects when consumed in moderation. Alcohol has been shown to raise HDL (“good”) cholesterol and prevent blood clots from forming.
One study of more than 1,900 adults who had been hospitalized for heart attack found that patients who consumed seven drinks a week in the year before their heart attack had a 32% lower risk of dying compared with teetotalers. And those who consumed less than seven drinks a week lowered their risk of dying by 21% over nearly 4 years, compared with patients who abstained from drinking. The findings suggest that alcohol consumption is probably safe after a heart attack for moderate drinkers. Patients who abstain from alcohol may need more aggressive treatment with drugs such as aspirin, beta-blockers, and cholesterol-lowering medications.
Another study found that elderly people who drank at least 1.5 drinks per day had a risk of heart failure 47% lower than abstainers, regardless of age, race, blood pressure, history of diabetes, smoking, and other factors. The study included 2,200 adults averaging 74 years of age.
SOURCE: Journal of the American Medical Association 2001;285:1965-1977.
Moderate Drinking Helps Preserve Women’s Mental Functioning
TORONTO (Reuters Health) - Consuming less than one alcoholic drink per day may help preserve the mental function of older women. Between 1995 and 1999, 9,072 women in the Nurses’ Health Study, aged 70 to 79, were interviewed. Mental function was assessed using seven different tests. Information about their alcohol use had been collected at the beginning of the study in 1980, and was updated through 1994. After adjusting for other factors that could affect mental function, the researchers found that the women who drank moderately had better average scores on five of the seven tests and on a score that combined all seven tests. The effect seen on cognitive function was the equivalent of being 1 or 2 years younger.
SOURCE: Presentation by Dr. Meir Stampfer (Professor of Epidemiology and Nutrition at Harvard School of Public Health) at the 2001 Congress of Epidemiology.
Study Sheds Light on Wine’s Benefits
(Molecules found in food and wine may help to extend life)
(Reuters) - In a research paper, Harvard scientists announced they have found a new class of chemicals that may extend life. The research is preliminary, but what makes it interesting is the chemicals can be found in some red wine.
Researchers have known for years that cutting calories can prolong life in everything from yeast cells to mammals. But an easier way to live longer may be as simple as turning a corkscrew. Molecules found in red wine, peanuts, and other products of the plant world have for the first time been shown to mimic the life-extending effects of calorie restriction. This could help researchers develop drugs that lengthen life and prevent or treat aging-related diseases. One of the molecules, resveratrol, was shown in a study to extend the life span of yeast cells by up to 80 percent. Resveratrol exists naturally in grapes and red wine.
David Sinclair, an assistant professor of pathology at Harvard Medical School and co-author of the study, said he and his fellow researchers hope the molecules will prove to prolong life not just in yeast but in multi-cellular organisms like worms, fruit flies, and perhaps humans. Sinclair, whose study appears in the journal Nature, said tests on worms and flies were already yielding “encouraging” results. Similar trials are already being planned on mice.
‘ENTHUSIASTIC’ OVER RED WINE
Sinclair said he has become more “enthusiastic” about the purported health benefits of red wine since his research began, and that experts who have reviewed his findings have had a similar response. “Not many people know about it yet, but those who do have almost invariably changed their drinking habits; that is, they drink more red wine,” he said.
The molecules that were shown to extend life in yeast belong to a family of compounds known as polyphenols. These include resveratrol, which is already thought to make red wine healthy in moderate amounts. Sinclair said the latest study may help explain why moderate consumption of red wine has been linked to lower incidence of heart disease and why resveratrol prevents cancer in mice.“We’re connecting many dots with this study,” he said.
Scientists have known for decades that putting organisms on a calorie-restricted diet dramatically reduces the incidence of age-related illnesses such as cancer, osteoporosis, and heart disease. In the 1990s, research showed that single genes can control how fast organisms age. Because of that, scientists have been racing to find ways of manipulating those genes.
Sinclair and his team have been looking for what he calls the Holy Grail of aging research: molecules that activate the enzymes that in turn influence the genes that regulate aging. Now, they say, they have found those molecules.
Sinclair’s team partnered with BIOMOL, a Pennsylvania company, to screen thousands of molecules to see which ones might activate the enzymes. Not only did they find a group of 18 molecules that fit the bill — resveratrol being just one — but all of them came from plants and were produced in response to harsh environmental conditions like drought.
“We think we know why these plants make these molecules. We think it’s part of their own defense response, and we also believe that animals and fungi that live on the plants can pick up on these clues,” he said.
To illustrate that theory, Sinclair noted that red wines from regions with harsher growing conditions — Spain, Chile, northern France, Argentina, and Australia — contain more resveratrol than those produced where grapes are not highly stressed or dehydrated.