What are the possible health benefits of drinking wine?

Wine, especially the red variety, has been studied extensively over many years with impressive findings suggesting it may promote a longer lifespan, protect against certain cancers, improve mental health, and provide benefits to the heart.

This Medical News Today article focuses on the health benefits of drinking wine. It includes a brief history of wine, as well as explaining what moderate wine consumption is. At the end of the article there is some information on resveratrol, a compound found in wine and some plants.

Most of the content and quotes in this article refer to red wine, however one study published by the Journal of Agricultural & Food Chemistry concluded for the first time that white wine may provide the same cardio-protective qualities as red wine.More studies on white wine are needed to confirm these results.However, as many more studies have focused on red wine, most of the content and quotes in this article refer to red wine.

What is moderate wine consumption?

“Moderate” wine consumption is said to be good for the health. But what is “moderate” wine consumption? How much wine you can drink in one sitting before the health benefits turn into dangers depends on many factors, including the person’s size, age, sex, body stature and general state of health, as well as whether it is being consumed with food or on an empty stomach.

Women absorb alcohol more rapidly than men because of their lower body water content and different levels of stomach enzymes. Therefore, moderate wine consumption will be a lower amount for women than for men.

According to “Dietary Guidelines for Americans 2010”⁴, published by the US Department of Agriculture, “If alcohol is consumed, it should be consumed in moderation – up to one drink per day for women and two drinks per day for men”.

The National Health Service⁵, UK, writes “Men should not regularly drink more than 3-4 units of alcohol a day. Women should not regularly drink more than 2-3 units a day.” One unit equals 10ml or 8g of pure alcohol. A 250ml (large) glass of 12% red wine has about 3 units of alcohol. A 175ml (medium) glass has about two units.

What are the possible health benefits of drinking wine?

Important note: All the health benefits associated with drinking wine that are listed below are only applicable to moderate drinking.

1) Reducing risk of depression

A team from several universities in Spain reported in the journal BMC Medicine that drinking wine may reduce the risk of depression.

The researchers gathered data on 2,683 men and 2,822 women aged from 55 to 80 years over a seven-year period. The participants had to complete a food frequency questionnaire every year, which included details on their alcohol consumption as well as their mental health.

The authors found that men and women who drank two to seven glasses of wine per week were less likely to be diagnosed with depression.

Even after taking into account lifestyle factors which could influence their findings, the significantly lower risk of developing depression still stood.

2) Preventing colon cancer

Scientists from the University of Leicester, UK, reported at the 2nd International Scientific Conference on Resveratrol and Health that regular, moderate red wine consumption can reduce the rate of bowel tumors by approximately 50%.

3) Anti-aging

Researchers from Harvard Medical School reported that red wine has anti-aging properties.

Specifically, resveratrol was the compound found to have the beneficial effect. The resveratrol in wine comes from the skins of red grapes. Blueberries, cranberries and nuts are also sources of resveratrol.

Head investigator, David Sinclair said “Resveratrol improves the health of mice on a high-fat diet and increases life span.”

Their findings, which were published in the journal Cell Metabolismoffer, was the first compelling proof of the definite link between the anti-aging properties of resveratrol and the SIRT1 gene.

Wine’s anti-aging properties have been talked about for over one thousand years. Monasteries throughout Europe were convinced that their monks’ longer lifespans, compared to the rest of the population, was partly due to their moderate, regular consumption of wine.

A study carried out at the University of London found that procyanidins, compounds commonly found in red wine, keep the blood vessels healthy and are one of the factors that contribute towards longer life spans enjoyed by the people in Sardinia and the southwest of France. The researchers also found that red wine made in the traditional way has much higher levels of procyanidins than other wines.

4) Preventing breast cancer

Regular consumption of most alcoholic drinks increases the risk of breast cancer. However, red wine intake has the opposite effect, researchers from Cedars-Sinai Medical Center in Los Angeles found.

In the Journal of Women’s Health, the scientists explained that chemicals in the skins and seeds of red grapes reduce estrogen levels while raising testosterone in premenopausal women – which results in a lower risk of developing breast cancer.

The authors emphasized that it is not just the red wine that has the beneficial compounds, but its raw material – red grape. They suggested that when women are choosing an alcoholic drink to consume, they should consider red wine. They reiterated that they were not encouraging wine over grapes.

The study surprised many researchers. Most studies point to a higher risk of breast cancer from consuming alcoholic drinks, because alcohol raises a woman’s estrogen levels, which in turn encourage the growth of cancer cells.

Study co-author, Dr. Chrisandra Shufelt, MD, said: “If you were to have a glass of wine with dinner, you may want to consider a glass of red. Switching may shift your risk.”

5) Preventing dementia

A team from Loyola University Medical Center center found that moderate red wine intake can reduce the risk of developing dementia.

In this study, the researchers gathered and analyzed data from academic papers on red wine since 1977. The studies, which spanned 19 nations, showed a statistically significantly lower risk of dementia among regular, moderate red wine drinkers in 14 countries.

The investigators explained that resveratrol reduces the stickiness of blood platelets, which helps keep the blood vessels open and flexible. This helps maintain a good blood supply to the brain.

Both white and red wines contain resveratrol, but red wine has much more. The skin of red grapes has very high levels of resveratrol. During the manufacturing process of red wine there is prolonged contact with grape skins.

Lead investigator, Professor Edward J. Neafsey, said “We don’t recommend that nondrinkers start drinking. But moderate drinking, if it is truly moderate, can be beneficial.”

Neafsey and colleagues wrote in The Journal of Neuropsychiatric Disease and Treatment that moderate red wine drinkers had a 23% lower risk of developing dementia compared to people who rarely or never consumed the alcoholic beverage.

In our look at the possible health benefits of wine consumption, here are numbers 6 to 13 for your consideration.

6) Protecting from severe sunburn

Wine and grape derivatives can help reduce the damaging effects of UV (ultraviolet) light, scientists from the University of Barcelona in Spain reported in The Journal of Agricultural Food and Chemistry.

The authors explained that when UV rays make contact with human skin, they activate reactive oxygen species (ROS), which oxidize fats, DNA and other large molecules, which in turn stimulate other enzymes that harm skin cells. Flavonoids, found in wine and grapes, inhibit the formation of the ROS in skin cells that are exposed to sunlight.

7) Preventing blinding diseases

Red wine can stop the out-of-control blood vessel growth in the eye that causes blindness, researchers at Washington University School of Medicine in St. Louis reported in the American Journal of Pathology.

Diabetic retinopathy and age-related macular degeneration, which is the leading cause of blindness among Americans aged 50+ years, are caused by an overgrowth of blood vessels (angiogenesis) in the eye.

The researchers explained that resveratrol is the compound in wine that protects vision. Grapes, blueberries, peanuts and some other plants are rich in resveratrol.

8) Damage after stroke

Red wine may protect the brain from stroke damage, researchers at Johns Hopkins University School of Medicine wrote in the journal Experimental Neurology.

Professor Sylvain Doré believes that resveratrol in red wine raises levels of heme oxygenase, an enzyme known to protect nerve cells in the brain from damage. When somebody suffers a stroke, the brain is ready to protect itself because of higher enzyme levels.

Doré added that nobody yet knows whether it is just the resveratrol that has the health benefits, or it is the alcohol in the wine which may be needed to concentrate the levels of the compound.

9) Improving lung function and preventing lung cancer

Dutch scientists reported on a study that looked at the effects of resveratrol, red wine, and white wine on lung function.

They found that:

• Pure resveratrol was good for lung function
• White wine was also good for lung function
• Red wine made no difference

A reviewer of the study wrote “Resveratrol may well be just the bystander of something else present in wine. The beneficial effects on lung function are probably related to many compounds present in wine, and not just resveratrol.”

According to a number of scientific studies, moderate wine drinkers appear to enjoy better lung function, the authors added.

In another study, a team from Kaiser Permanente wrote in the journal Cancer Epidemiology, Biomarkers and Prevention that red wine consumption may reduce lung cancer risk. Chun Chao, Ph.D., said “An antioxidant component in red wine may be protective of lung cancer, particularly among smokers.”

10) Raising levels of omega-3 fatty acids

Wine is better than other alcoholic drinks in raising levels of omega-3 fatty acids in plasma and red blood cells, according to the IMMIDIET study involving European researchers from various countries.

The study, published in the American Journal of Clinical Nutrition, examined 1,604 adults from London in England, Abruzzo in Italy, and Limburg in Belgium. They all underwent a comprehensive medical examination with a primary care physician (general practitioner) and also completed an annual food frequency questionnaire which included details of their dietary and drinking habits.

They found that regular, moderate wine drinkers had higher blood levels of omega-3 fatty acids, which are usually derived from eating fish. We know that omega-3 fatty acids protect against coronary heart disease.

The scientists found that drinking wine acts like a trigger, boosting levels of omega-3 fatty acids in the body.

11) Preventing liver disease

A study carried out at the UC San Diego School of Medicine concluded that modest wine consumption reduced the risk of non-alcoholic fatty liver disease by half compared to people who never drank wine. Their finding challenged conventional thinking regarding alcohol consumption and liver health.

The researchers reported in the journal Hepatology that regular, modest beer or liquor drinkers had more than four times the risk of non-alcoholic fatty liver disease compared to the wine drinkers.

12) Protecting from prostate Cancer

A study published in the June 2007 issue of Harvard Men’s Health Watch reported that male moderate red wine drinkers were 52% as likely to be diagnosed with prostate cancer as men who never drank red wine.

They defined moderate drinking as an average of four to seven glasses of red wine per week.

Initially, the Seattle researchers looked at general alcohol consumption and found no link to prostate cancer risk. However, when they went one step further and looked at different alcoholic beverages, they identified a clear association between red wine drinking and lower prostate cancer risk.

Even extremely moderate red wine consumption (one glass per week) reduced men’s risk of prostate cancer by 6%, the authors informed.

13) Preventing type 2 diabetes

In an animal experiment, scientists at the Chinese Academy of Sciences discovered that a chemical found in red wine and the skin of red grapes – resveratrol – improved sensitivity to insulin. Insulin resistance is the most important critical factor contributing to type 2 diabetes risk.

The researchers reported in the journal Cell Metabolism that resveratrol also increased levels of the enzyme SIRT1, which was found to improve insulin sensitivity in mice.

Study leader, Qiwei Zhai said that red wine may have some benefits for insulin sensitivity, but this needs to be confirmed in further studies.

Recognising an imbalance

It is important to note that the frequency you drink is not the sole indication of a potentially  imbalanced relationship with alcohol.  Periods of heavy drinking in a short amount of time  – referred to as binge drinking –  may be quite infrequent (for example, weeks or even months apart), giving rise to the misconception that binge drinking is less dangerous than full-blown alcoholism.

Dependence and addiction can creep up.  Australian residents can access more information, resources and support here.