Is wine good for you?
The botanical name for the common grapevine is Vitis vinifera and of the thousands of cultivars only around 30 grape varieties are commonly cultivated for wine production. Wine is made by the fermentation of grape juice obtained by crushing the grapes and then adding yeast to convert most of the natural sugars (glucose and fructose) in the grape juice into alcohol and carbon dioxide. The carbon dioxide is then released from the wine mixture into the air and the alcohol remains. After the primary fermentation, the liquid is transferred to vessels for the secondary fermentation or â€œageingâ€ process whereby the remaining sugars are slowly converted into alcohol and the wine becomes clear. Fining agents are used during winemaking to remove tannins, reduce astringency and remove microscopic particles that cloud the wines.
Wines are aged in either oak barrels or stainless-steel tanks before bottling. Sometimes oak chips are added to wine that is fermenting in stainless steel in order to enhance the taste. This process is mainly used in cheaper wines.
Red wines are produced by de-stemming and crushing the grapes into a tank and leaving the skins in contact with the juice throughout the fermentation. The presence of grape skin makes the wine red in colour. The most popular red varieties used in Australia include Cabernet Sauvignon, Merlot, Pinot Noir and Shiraz, while Cabernet Franc and Grenache are often used in blends.
White wines are mostly processed without de-stemming or crushing and are transferred from picking bins directly to the press. In contrast to the production of red wine, the juice is not left in contact with the grape skins while fermenting, resulting in a wine that varies in colour from golden yellow to a very pale yellow or light straw colour. The most common types of white wines include Chardonnay, Sauvignon Blanc, Riesling and Semillon.
RosÃ©-style wines are made by pressing ripe, red grapes but leaving the juice in contact with the skins for just a short time to extract the desired colour, usually a pale pink. The skins of the grapes are removed halfway through fermentation. Consequently, the flavour of rosÃ©s falls midway between whites and reds.
Sparkling wines contain carbon dioxide and come in red or white varieties. There are various methods by which those refreshing bubbles make it into your wine. Carbon dioxide may be injected into the wine, but this produces big bubbles that dissipate quickly in the glass. The Metodo Italiano, or the Charmat process, is one in which wine undergoes a secondary fermentation in bulk tanks and is bottled under pressure, producing smaller, longer-lasting bubbles. This is now used widely around the world to produce light, delicate, sparkling wines that are ready to drink. Then thereâ€™s the traditional method or mÃ©thode champenoise. With this method, the bubbles for more complex wines are produced by secondary fermentation in the bottle. This method is used for the production of Champagne and other quality sparkling wines and is more expensive than the Charmat process.
Dessert wines are sweet, containing between 50 and 400 grams of sugar per litre of wine and are often drunk after meals in place of or with dessert. They are made by the premature cessation of the fermentation process, which ensures that varying residual sugar levels remain in the wine. In other cases, the winemaker may choose to hold back some of the sweet grape juice and add it to the wine after the fermentation is complete, a technique known as sussreserve.
Fortified wines such as port are more alcoholic than other wines. The fermentation process is halted with the addition of a spirit, such as brandy, or the additional spirit may be added after the fermentation process is complete.
Wine contains many intriguing antioxidants. They are generally found in much higher concentrations in red wine as they mainly occur in concentrated amounts in the skins of the grapes, which are included in the red wine fermentation process. The OPCs are an exception, being found in the seeds of the grapes.
- Produced by grapevines, in response to injury
- Concentrations tend to be higher in cooler climates because of its role in the defence of the vine against fungal infections
- Plays a role in the prevention of cardiovascular diseases
- Prevents blood-clot formation
- Reduces LDL cholesterol levels
- Reduces the risk of atherosclerotic plaque build-up
- A phyto-oestrogen â€” may be beneficial for menopause support
- Inhibits the growth of certain cancerous cells
OPCs (oligomeric procyanidin complexes)
- Found in grape seeds
- Help protect against the effects of environmental stresses such as cigarette smoking and pollution
- Hve vasodilatory properties
- Lower blood fat
- Lower blood pressure
- Prevent blood-clot formation
- Counteract the negative effects of high cholesterol on the heart and blood vessels
- Naturally occurring in grape skins and stems
- Protects grapes from ultraviolet light damage â€” the more grapes are exposed to sunlight, the more quercetin they contain
- Levels are also higher in wines derived from thick-skinned grape varieties, such as Cabernet Sauvignon, which have a high skin-to-volume ratio
- Reduces blood clotting
- Reduces LDL cholesterol levels
- Inhibits the growth of certain cancerous cells particularly in the breast, colon, prostate and lung
- The primary catechins in wine are catechin, epicatechin and gallate epicatechin
- Catechins react with tannins to make the primary flavour component in red wine and are the main source of astringent and bitter sensations
- Dilate blood vessels
- Lower LDL cholesterol levels
- Reduce atherosclerotic plaque formation
Wine in your body
Alcohol consumed in low to moderate amounts is thought to help reduce the risk of heart disease. It has been proposed that wine consumption may explain why the death rate from coronary heart disease in France remains relatively low despite a diet very high in saturated fat. This phenomenon has become known as the â€œFrench paradoxâ€. A similar pattern of diet and alcohol consumption has also been found in other southern European countries where heart disease rates are lower compared with other parts of the world. A landmark study, the Copenhagen City Heart Study, published in 1995 in the British Medical Journal, concluded: â€œLow to moderate intake of wine is associated with lower mortality from cardiovascular and cerebrovascular disease and other causes.â€
Many research studies analysing the relationship between wine and heart disease have since been undertaken. Itâ€™s now known that a large proportion of the risk reduction is due to moderate alcohol intake raising HDL (â€œgoodâ€) cholesterol concentrations in the blood, inhibiting the formation of LDL (â€œbadâ€) cholesterol and reducing the risk of blood clots. Red wine, in particular, contains flavonoids such as quercetin and catechins that act as antioxidants, which help to reduce the build-up of atherosclerosis (collection of fat on the inner walls of arteries). The oligomeric proanthocyanidins (OPCs) are antioxidants found in red wine that help maintain the flexibility of the blood vessel walls and lower blood pressure by reducing endothin-1, a molecule involved in blood pressure regulation.
Your risk of stroke can be reduced with moderate alcohol intake (one to two glasses a day), while excessive amounts of alcohol can raise blood pressure and increase your risk of stroke. A 16-year Danish study on the relationship between wine and incidence of stroke has revealed that compared with abstainers, individuals who drank wine on a monthly, weekly or daily basis had a 16 per cent, 34 per cent and 32 per cent reduced risk of stroke, respectively. The effect of red wine on preventing ischemic strokes is thought to be due to its role in preventing blood clot formation.
The jury still appears to be out when it comes to wine consumption and cancer. While some studies have reported that light to moderate consumption of red wine is associated with a reduced risk of certain cancers such as lung and prostate cancer, other studies have shown that drinking even one glass of wine a day increases your cancer risk.
In February this year, a large study conducted in the UK, involving 1 million women, found that a daily drink of any type of alcohol significantly raised the risk of breast, liver and rectal cancer and was estimated to account for more than 7000 extra cases of cancer each year. A 2007 World Cancer Research Fund Report showed excessive alcohol intake increases the risk of cancers of the mouth, pharynx, larynx, oesophagus, colon and breast.
Another study, conducted in March 2009, found that, although women who drink more than 14 alcoholic drinks a week had a 24 per cent increased risk of breast cancer, this risk was not observed when the choice of alcohol was wine.
One thing is certain, though: excessive or binge drinking on a regular basis does increase your risk of developing many types of cancer.
Mood and memory
A drink or two can make you more sociable, carefree and uninhibited and can bring stress relief at the end of a hard day, but alcohol can also have negative effects on the mind. Alcohol can cause memory impairments and interfere with your ability to form new long-term memories, as well as cause memory blackouts. Alcohol affects memory by disrupting the hippocampus, a part of the brain crucial to memory and navigation.
Since alcohol is a depressant, it will have a greater effect on mood when a person is stressed or depressed. Alcohol will initially make you feel happy and more relaxed, but it also has the potential to increase anxiety and cause mood swings and depression, particularly when higher amounts are consumed.
Research has revealed that red wine may reduce the incidence of Alzheimerâ€™s disease. Red wine antioxidants block the formation of proteins that build the toxic plaques thought to destroy brain cells, and lower the toxicity of existing plaques, thus reducing cognitive deterioration.
Recent laboratory studies have shown that resveratrol was able to help a brain enzyme regenerate neural cells. The antioxidant was tested on human neural cells and found to make the brain cells grow extensions, which helped them to connect with each other. Itâ€™s believed this could help in the treatment of diseases such as Parkinsonâ€™s and Alzheimerâ€™s where the links between neural cells break down, causing mental confusion, dementia and muscle problems.
On the flipside, excessive alcohol consumption and binge drinking wreak havoc with your internal organs, leading to many serious health conditions, such as liver cirrhosis (irreversible scarring of the liver), stomach ulcers and gastrointestinal complications, and can lead to fertility problems, weight gain, depletion of certain vitamins and minerals, high blood pressure and increased risk of heart attack, cancer and other degenerative diseases.
Wine and sulphites
Sulphur-based preservatives such as potassium metabisulphite (224) and sulphur dioxide (220) are added to wine to prevent bacterial spoilage and ensure a longer shelf life. Up to 100mg/litre (of sulphur dioxide) can be added, but the â€œavailableâ€ or â€œfreeâ€ sulphur dioxide levels should be kept to 30mg/litre. Available sulphur dioxide should be maintained at this level until bottling. A final dose of sulphite is then added to help prevent unwanted fermentation in the bottle. The levels of sulphites in wine average 80mg/litre.
Sulphites are also naturally produced by the fermentation process, coming from the skin of the grapes, hence higher sulphite levels are used to preserve white wines. There are only a few types of wines on the market that are made without the addition of sulphites. In â€œpreservative-freeâ€ wine, no sulphur has been added to the wine and sulphite content is less than 10mg/litre of wine.
Sulphites have been linked to health symptoms, including headaches, rashes, hives, abdominal pain, nausea, vomiting, diarrhoea, respiratory problems such as asthma and other allergic reactions.
For wine to be certified organic, it must be produced using organic grapes and manufactured in a certified organic winery. The sulphite content of organic wine is limited to less than 20mg/litre. All stages in the cycle of wine production must comply with organic certification standards, from the cultivation and processing of grapes to the final packaging.
Some of the natural methods used by organic grape producers to manage pests, weeds and disease include disruption of pestsâ€™ breeding cycles (eg undervine weeding helps manage garden weevil populations), growing plants to create a habitat, which encourages beneficial predators (eg ladybirds help control unwanted pests) and planting beneficial weeds to out-compete with other weeds.
Biodynamic farming has similarities with organic farming, such as emphasising the use of manures and composts and excluding of the use of artificial inputs and genetically modified organisms on soil and plants. However, the biodynamic approach employs unique methods such as the use of particular fermented herbal and mineral preparations as compost additives and field sprays. Homoeopathic amounts of these preparations are applied to help improve soil quality and encourage vines to better assimilate nutrients, trace minerals and water for balanced growth.
The use of an astronomical sowing and planting calendar, ie planting by the moon, is also employed in accordance with bio-rhythms associated with plant growth, so depending on lunar cycles, some days are better than others for ploughing, planting or harvesting.
Guidelines to reduce health risks from alcohol
- The lifetime risk of harm from drinking alcohol increases with the amount consumed. For healthy men and women, drinking no more than two standard drinks on any day reduces the lifetime risk of harm from alcohol-related disease or injury.
- On a single occasion of drinking, the risk of alcohol-related injury increases with the amount consumed. For healthy men and women, drinking no more than four standard drinks on a single occasion reduces the risk of alcohol-related injury arising from that occasion.
- For children and young people under 18, not drinking alcohol is the safest option.
- For women who are pregnant, planning a pregnancy, or breastfeeding, not drinking is the safest option.
Source: The Australian Health and Medical Research Council, February 2009
If you enjoy the occasional glass of wine with dinner, choose red for its additional antioxidant properties, but ensure you keep it in check to avoid any nasty health complications. The recommended amount of alcohol consumption to avoid health risks for males under 65 is no more than two standard drinks a day. If youâ€™re a female of any age or a male 66 and older, the recommended amount is one standard drink a day to avoid health risks. A standard drink is 355mL of beer, 150mL of wine or 45mL of 80-proof distilled spirits.
If you have heart failure or a weak heart, or if you are pregnant, itâ€™s best to avoid alcohol completely. If you have questions about the benefits and risks of alcohol, talk to your doctor about specific recommendations for you.
Saskia Brown is a naturopath practising in Sydney from Neutral Bay Health and Wellbeing and specialising in allergies, asthma and healthy weight management. E: firstname.lastname@example.org