Scientists have known for a long time that there is less coronary heart disease in regions of the world where the normal diet includes high amounts of fruits, vegetables and also red wine, even when other health dangers - high fat consumption, smoking and stress, for instance, are similar. Studies now suggest that it is the high antioxidant properties in this type of daily diet, which provide such healthy protection. Special attention was given specifically to health benefits of red wine despite its alcohol content.

            For so many years, evidences and recent scientific studies have accumulated and suggested that drinkers of alcohol in moderate quantities, specifically red wine, have lower risk of heart diseases compared to nondrinkers and heavy drinkers. However, questions such as how and what were the components responsible for that have always been raised. 

            The debate on the benefits of alcohol began from research in France showing a remarkably lower death rate of French people from coronary heart disease compared to other industrialized countries. This is due to their moderate intake of red wine despite their high fat diet, contributing to the explanation for what they have stated as the “French Paradox”.

            Red wine, despite its alcohol content, is a rich dietary source of phytonutrients in the form of phenolic compounds and or flavonoids. These compounds are considered to be the nonalcoholic component of red wine, recently thought to have a role in the prevention of oxidative stress-linked diseases mainly due to their antioxidant capablity.

            Although some still believe that the beneficial effects of red wine consumption are due largely to their alcohol component, many others believe that it is the nonalcoholic components. This debate led scientists to research and study further on the component of red wine that is responsible for its protective effect, specifically on heart diseases.

 

COMPARING RED WINE WITH OTHER BEVERAGES

Researchers have discovered that one reason for the low rate of coronary heart disease is the presence of phenol related compounds such as resveratrol and flavonoids in wine, especially red wine.

Red grapes are one of the richest known sources of these compounds, which are concentrated in the seeds and skin. These nutrients may make red wine a healthier choice than white wine.

Red wine is made by allowing the red grape juice to remain in contact with the seeds and skins during the fermentation process. The extended contact between red wine and grape seeds and skins ensures a high flavonoid content in that beverage.

In contrast, white wine is made by juicing grapes, which immediately separates the seeds and skins from the wine before fermentation. The negligible contact between white wine and the grape seeds and skins during the fermentation process minimizes enrichment with flavonoids. Studies show that these compounds can lower harmful low density cholesterol while boosting beneficial high density cholesterol levels.

In addition, researchers from UC at Davis, also found that flavonoids in commercial white and red grape juices significantly inhibited the oxidation of LDL, as well as in extracts of rosemary, green tea, berries, and peaches. Therefore, grape extracts and juices, especially red grape juices, many fruits and green tea provide significant sources of flavonoid antioxidants that like wine may have potential beneficial health effects in protecting against atherosclerosis and other degenerative human diseases. They represent a positive potential in our diet that requires further research to improve our understanding of their mechanism of action.

 

PHYTONUTRIENTS AS ANTIOXIDANTS IN RED WINE       

            As mentioned earlier, one of red wine’s essential components are the phytonutrients or phytochemicals that are present in the form of phenolic compounds and flavonoids.

            The term “phytonutrients” became familiar to us nowadays due to its antioxidant and cancer-preventing capacity. These phytochemicals refer to hundreds or even thousands of biologically active compounds found in plants. While these phytonutrients perform vital functions for plants, it is their effect on humans, when ingested on fruits and vegetables that interested scientists. Essentially, phytonutrients protect us from the harmful effects of substances called free radicals, which accumulate in the body through natural metabolic processes, as well as through exposure to environmental contaminants and stress.

            To understand how phytonutrients act as “antioxidants”, we must learn what antioxidants and free radicals are. Antioxidants have been shown to protect cells against the destructive activities of molecules called free radicals. These free radicals, whether produced by the body’s own metabolism, carcinogens or radiation, can attack DNA in cells through a process called oxidation. The genetic mutation that can result plays a key role in the development of cancer. Antioxidants also prevent the oxidation of unhealthy LDL cholesterol into plaque, the substance that clogs arteries and contributes to cardiovascular disease. This form of cholesterol injures the lining of blood vessels, leading to the build-up of cholesterol deposits. These deposits block flow through blood vessels, causing symptoms such as angina. If a piece breaks free, it can block a small blood vessel in the heart, resulting in a heart attack. Reducing the amount of oxidized low density cholesterol in the blood is a good way to decrease the chances of heart disease.

Scientists generally agree that dietary antioxidants appear to help prevent both heart disease and cancer, known to be the leading causes of death in the U.S., by protecting the body from oxidative damage.

 

 

PHENOLIC COMPOUNDS FOUND IN RED WINE

            Of the many fruits and vegetables containing phytonutrients, grapes have been the subject of many research by many scientists for so many years now because of several compounds found in it, having positive effects on our health.

            Responsible for much of the flavor, color and body of wine, grapes, containing phenolic compounds, are a major component of wine. Benzaldehyde (vanillin) and Benzoic acid (Vanillic and Gallic acids) are the phenolic compounds one tastes the most in wines. However, chemical compounds like resveratrol and three others, catechin, anthocyanin, and quercetin, collectively known as flavonoids or phenols are also found in red wine.

            Catechins may make up the largest quantity of phenols. Anthocyanins are responsible for the pigmentation of red wine, and are present in proportion to the color of the wine. Resveratrol (trans-3,5,4'-trihydroxystilbene), a compound found largely in the skins of red grapes, attributed with reducing cholesterol, is also one of the major components of red wine.

 

HEALTH BENEFITS OF RED WINE WITHOUT ALCOHOL

            Since debate on what really is responsible for most of the health benefits of red wine, researches and studies have been made to somehow clear the issue. Experimentations have also been conducted and comparison between the role of alcoholic and nonalcoholic components of red wine has been established.

            The American Journal of Clinical Nutrition reports that red wine, without the alcohol, is also good for the heart. Dr. Jennifer R.C. Bell and her colleagues at the University of California took a 1996 Cabernet Sauvignon and removed the alcohol content. They then asked 5 men and 4 women, all healthy, to drink about ½ cup of the de-alcoholised wine, with water added on one day and water and ethanol added on the other. The levels of flavonoid - catechin - the wine component credited with heart benefits –were monitored before and after consumption.

The researchers found that the dealcoholised wine produced a greater benefit than the standard red wine. The half-life of the catechin was significantly shorter (3.17 hours) when subjects, irrespective of gender drank alcoholic red wine than when they drank the dealcoholised version (4.08 hours).

Also, researchers at University of California at Davis have discovered that an alcohol-free wine substitute raised flavonoid levels higher and kept them in the bloodstream longer than did the red wine with its alcohol content intact.

 

PLASMA ANTIOXIDANT CAPACITY OF RED WINE POLYPHENOLS

            Serafini et. al. investigated the hypothesis that the ingestion of alcohol-free red wine increases the antioxidant potential in humans and that this effect is due to the prompt absorption of the wine’s polyphenol fraction. They evaluated the effect of nonalcoholic fraction of red and white wines on total radical-trapping antioxidant parameter (TRAP) and on total plasma polyphenols in vivo in humans.

In order to determine the contribution of the alcohol in wine to this effect, a group of 10 healthy people drank 113 mL of tap water, alcohol-free red wine and alcohol- free white wine at one-week intervals. After each session, measurements were made of their plasma antioxidant capacity (reported as total radical-trapping antioxidant parameter (TRAP)), and whether this response was associated with increased phenolic compounds in their plasma.

            They showed that alcohol-free red wine displays a stronger in vitro antioxidant activity than alcohol-free white wine having its phenolic contents as the only consistent difference. Their findings suggest that the in vitro peroxyl-radical scavenging activity of alcohol-free red wine is proportional to its higher phenolic compound concentration. In vivo studies showed that the antioxidant potential in humans responds to the oral ingestion of phenol-rich beverages such as red wine. This response was believed to be elicited by the rapid absorption into the circulation of polyphenols, showing that the reduced LDL oxidation after dietary consumption of red wine was associated with an increase in total polyphenol levels in plasma LDL. They also demonstrated that the nonalcoholic fraction of red wine does significantly increase total plasma antioxidant activity, which is directly proportional to an increase in plasma concentrations of phenolic compounds. Thus, the changes in plasma antioxidant potential may be attributed to the nonalcoholic, phenolic fraction of red wine.

The researchers in Ankara also did not find antioxidant potential in ethyl (drinking) alcohol. A 1997 study in the American Journal of Cardiology found that wine, but not ethyl alcohol, inhibits LDL oxidation, suggesting that wine have benefits independent of its alcohol content.

 

ROLE OF ALCOHOL COMPONENT IN RED WINE

            Due to the results of other studies conducted, showing and suggesting a separate role for the alcoholic component of red wine, the issue or debate still was not solved. Alcohol apparently offers protection independent of any antioxidant benefit. A review of 42 studies conducted between 1965 and 1998 recently published in the British Medical Journal found that moderate alcohol consumption raised levels of some heart-friendly compounds, including "good" cholesterol (high-density lipoproteins--HDL-C). It also lowered concentrations of fibrinogen, a substance that can contribute to blood clots. Reviewers estimated that the rise in HDL-C levels alone would decrease heart disease risk by 16.8%.

            Scientists found out that the positive effects of moderate quantities of alcohol were attributed in part to an increase in plasma levels of HDL and to an inhibition of platelet aggregation through a reduction in thrombotic tendency. Alcohol has also been shown to affect platelet activity indirectly, through an HDL-mediated stimulation of the production of prostacyclin, a potent vasodilator and platelet anti-aggregator. There are, however, also contrary effects of alcohol. Ethanol metabolism is responsible for the generation of free radicals. It may also enhance lipid peroxidation and may reduce glutathione levels in hepatic cells.

            Serafini et. al. reported that the ethanol moiety of wine is likely to improve the absorption of phenolic compounds by reducing its interaction with salivary proteins.

            On the other hand, chronic alcohol intake predisposes an individual to more frequent and more severe illnesses. Although many environmental factors contribute to this, studies indicate that ethanol is directly immunosuppressive, which is derived from free radical damage. As mentioned, ethanol is a powerful generator of oxygen free radicals when detoxified in the liver. Studies have also shown that alcohol consumption suppresses the immune system. Reductions in NK (natural killer) cells’ activity and T-cell dependent reactions have also been documented. A study done by Percival and Sims tested the hypothesis contradicting the immunosuppresive effect of ethanol consumption, wherein in the form of red wine, ethanol consumption would not suppress an immune response because of the antioxidant activity of phenolics found in red wine. They tested the lymphocyte response to lipopolysaccharide challenge after ingestion of alcohol in the form of red wine in comparison to those who ingested ethanol only. Their results supported that hypothesis and they have concluded that some of the phytochemicals in red wine, although not specifically identified, can overcome the detrimental effects of ethanol on the immune system, wherein the protective effect may be related to the alterations in the enzymes responsible for detoxification of alcohol.

            Lab tests performed in UK, found that antioxidant levels for red wines were greater than 15 milimols per liter (mmol/L). Only tea had levels equal to or higher than red wine, although researchers speculate that the presence of alcohol in wine helps maintain the stability of the antioxidants and enhances absorption.

"Alcohol allows antioxidants to dissolve more freely and encourages absorption into the body. Wine solubilizes the polyphenols better and absorption prevents the deterioration of antioxidants," explained Dr. Martin, a research scientist with Randox Laboratories Ltd., the United Kingdom-based company that developed the test.

            It has also been found out that once in the body, wine's phenolic fraction is precipitated by proteins; however, increasing amounts of alcohol in wine will partially restore the antioxidant activity lost as a consequence of this interaction. Thus, the alcoholic fraction of wine, by reducing the chemical interactions between proteins and red wine phenolic compounds, may contribute indirectly to the antioxidant capacity of wine by increasing the bioavailability of its phenolic compounds

 

OTHER HEALTH BENEFITS OF RED WINE

            For hundreds of years moderate wine consumption has been recommended due to its various health benefits. In addition to its protective effect on the heart specifically on reducing certain heart diseases such as CHD, it has also been discovered as helpful for the treatment of iron deficiency anaemia, to help vegetarians increase their mineral absorption, and to help reduce the incidence of troublesome sleep disorders. The traditional use of wine with meals offers many benefits including aiding the digestive process.

            From the prevention of neurodegenerative diseases such as Alzheimer's and Parkinson's Disease to the prevention of cardiovascular diseases, from preventing food poisining, dysentery and so-called "traveler's diarrhea" to reduction in human mortality rates, the benefits of red wine consumption are piling up. Indeed, more than 100 scientific reports have been published since 1991 providing strong evidence that moderate wine consumption can be part of a healthy lifestyle.

            Most recently, a carefully designed study from researchers at the University of California, Davis, found that mice fed with wine solids were free of cancer tumors 40% longer than sibling mice with no wine in their diets. Wine-fed mice were found to have much higher concentrations of catechin, a wine compound previously shown to possess antioxidant properties.

"We discovered that the wine solid supplement delayed tumor onset, that intact catechin was absorbed, and that the supplemented diet supported normal growth and reproduction for three generations," explains Andrew Clifford and colleagues in the American Journal of Public Health.

Along with catechin, other phenolic compounds plentiful in wine, fruits and vegetables have been the subject of additional recent studies involving cancer. Trans-resveratrol in red wine, in a study from researchers at Old Dominion University in Virginia, was measured for its potential estrogenic activity—high estrogen being one of the known factors positively associated with breast cancer. The results suggest, say researchers R.L. Williams and colleagues, that trans-resveratrol is "a very potent antagonist" to estrogen binding, "which may provide some beneficial effects in areas such as breast cancer."

Another common wine phenolic, quercetin, has been found to inhibit growth of human breast cancer cells. Recently, a research team from the University of Western Ontario found that orange juice flavonoids most effectively inhibited breast cancer cell growth when combined with quercetin. Their study also pointed out that different antioxidant compounds may have more powerful anti-cancer effects at lower concentrations when combined synergistically.

       Compounds in wine have also been found to be more effective than Vitamin E in protecting LDL from oxidation, and beneficial effects appear to be widely distributed among a variety of major compounds.

Other research has found that phenolics in wine are indeed absorbed into the bloodstream, raising serum antioxidant levels in the blood. Wine consumption was also shown not to be associated with the potentially damaging "platelet rebound effect" sometimes responsible for sudden strokes after an episode of very heavy drinking.

            As studies over the past few years continue to associate general flavonoid intake with good health, researchers at UC-Davis continue to build data showing that wine's compounds are particularly potent. Compounds in wine have been found to be more effective than Vitamin E in protecting LDL from oxidation, and beneficial effects appear to be widely distributed among a variety of major compounds.

            Meanwhile, a separate study revealed that patients with heart disease should avoid wine. Considered the first study to investigate the effects of alcohol in secondary prevention of coronary heart disease, it appears that red wine can prevent heart disease but once the disease has developed, consuming red wine cannot alleviate it, according to a presentation at the 20th Congress of the European Society of Cardiology.

The researchers found that alcohol use was associated with increased blood pressure and increase glucose levels (both major risk factors for heart disease) among patients who ate a carbohydrate-rich Mediterranean-style diet. Alcohol also decreased platelet activity in the blood making blood particles stickier and more likely to clot among patients who ate a high-fat or Western-style diet.

The researchers say past studies on consumption of wine or other forms of alcohol have been performed with patients who are in relatively good health. "This study should lead us to seriously reconsider the current practice about alcohol recommendations to patients."

 

CONCLUSION

            As the current researches on the role of antioxidants points out, the beneficial effects seen among wine drinkers are likely to derive from the many components in wine—in addition to its ethyl alcohol content. The combination of alcohol and phenolic compounds, say some prominent researchers, could result in synergistic benefits not yet fully understood. Continued study of antioxidants promises to be one way to better understand and, potentially, prevent illnesses like cancer and heart disease.

The results of this new researches suggest that red wine provides two independent factors - one related to the alcohol content and the other to the flavonoid content - both capable of contributing to vascular health when consumed in moderation. In conclusion, these presented researches demonstrated that the consumption of wine in moderate amounts, and in particular red wine, is cardioprotective. It was also highlighted that the roles of the ethanol and phenolic components of wine in protection may be inter-related, where a synergistic combination of the differential effects of the different phenolic compounds may be necessary for maximum cardioprotection.

Since studies have repeatedly found that moderate daily wine consumption (one to two glasses per day) appears to be more beneficial than abstinence or over consumption. A glass of wine can be both pleasurable and relaxing and has a favourable influence on mood and sociability, some important ingredients of well-being. But remember that a healthy lifestyle also includes regular exercise and a diet that is low in fat and high in fresh fruit, vegetables and grains.

 

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