Is Drinking a Bottle of Wine Each Night Harmful to Health?

Drinking that much alcohol every day increases the risk of a range of serious illnesses (e.g. cancers and liver disease) and, depending on the context, potentially also increases risk of injuries.

The degree of risk varies according to specific diseases. It is important to note that this is only risk and not certainty. It means that if a population of 1000 people each were to drink half a bottle of wine a night for 30 years, there would be a significant increase in the rates of different diseases and injuries they would experience collectively compared with the situation in which they drink less alcohol or none at all. The risk for any individual person would be relatively small but still significant.

It is well established for example that even one glass of wine a day increases a woman’s risk of breast cancer. The extent of this risk was illustrated in a recent BMJ Open paper showing that the increased risk of cancer from 10 drinks of alcohol per week was the same as from 10 cigarettes a week for women.

It’s also important to emphasise that there is now serious scientific dispute about the veracity of purported health benefits from moderate drinking. The evidence for these is based on uncontrolled observational studies of how lifestyle behaviours like drinking predict future health outcomes. There are now a number of established biases and confounding effects that impact such studies which make people who continue to drink moderately appear healthier than those who become abstainers over the life course.

Work is ongoing to estimate the full impact of these factors and whether any significant benefits remain at all e.g. in relation to cardiovascular disease and diabetes.

Aside from its flavours, and capacity to help people relax, wine has gained something of a reputation as a “healthy” alcohol — with researchers in the past noting associations between red wine drinking in France, and lower incidence of heart disease.

However, wine drinking is also known to increase risks of serious health issues, including liver cirrhosis, sudden cardiac death, alcoholic cardiomyopathies and cardiac rhythm disorders. Excessive consumption and chronic misuse of alcohol are risk factors contributing to an increase in global disease.

How does the average drinker know what to believe? And how much wine is safe? As medical researchers, we published an in-depth analysis of the anatomy of wine. This included analysis of the risks and benefits of consumption, comparisons with other alcoholic beverages and a discussion around wine’s much publicised health benefits.

Wine and heart disease

Modern scientific intrigue surrounding wine has grown immensely since the 1970s, when large, international studies first reported a link between light-to-moderate consumption of alcohol and lower rates of ischemic heart disease (IHD) occurrence and associated deaths. IHDs are a group of diseases characterised by a reduced blood flow to the heart, and account for significant deaths worldwide.

Similar results have been reported individually for wine, specifically red wine. This phenomenon was eventually coined “the French paradox” after Renaud and de Lorgeril, two scientists who became known for this work, observed a relatively low risk of IHD-associated mortality in red wine drinkers despite a consumption of a diet rich in saturated fat.

Does this mean red wine is good for the heart? This is a complex question and as yet there is no consensus on the answer. More than one factor needs to be considered in order to explain this situation. Drinking patterns, lifestyle characteristics and dietary intake are all important for individuals to obtain a healthy cardiovascular profile.

The Mediterranean diet has been put forward as one explanation. This diet emphasizes consumption of plant-based foods in addition to the moderate consumption of red wine and has been labelled as beneficial by scientific advisory committees.

In the Mediterranean diet, the low-consumption of saturated fat, emphasis on a healthy lifestyle, and more independently, alpha-linoleic acid (an essential fatty acid) and red wine, may allow this diet to confer the much researched cardio-protective benefits.

Cholesterol, inflammation, blood pressure

Red wine contains over 500 different chemical substances. One class, called “polyphenols,” has been widely investigated for imparting the apparent antioxidant and anti-inflammatory effects of red wine.

Alcohol and polyphenols are thought to have several positive health impacts. One is a contribution to an increase in HDL-cholesterol or “good cholestrol” and a decrease in LDL-oxidation or “bad cholesterol.” They also contribute to a decrease in inflammation. They are thought to increase insulin sensitivity. And they are understood to improve blood pressure.

There is no consistent pattern when wine is compared to beer and spirits. Some report wine’s superiority in a reduction from IHD and mortality. Others report it for beer and spirits. Others suggest there is no difference. This suggests that alcohol and polyphenols both contribute to explaining the French paradox, in addition to lifestyle factors.

Despite the beneficial effects of wine and alcohol consumption, drinking is still a potential risk-factor for atrial fibrillation, the most-common “rhythm alteration” of the heart.

How much should you drink?

In much of the research, adverse effects were increasingly observed with excessive or binge-consumption of wine, while low-to-moderate intakes lowered IHD and mortality risks.

In response, various governing bodies have come forth with guidelines for alcohol consumption. These follow similar patterns, but vary remarkably by country and source. And the definition of “one standard drink” used in each guideline is highly variable, and discrepant between country borders. This causes great confusion. Readers should be wary of this when interpreting alcohol consumption guidelines.

The World Health Organization recommends low-risk alcohol consumption of no more than two standard drinks per day with at least two non-drinking days during the week. Here one standard drink is defined as 10 g of pure ethanol.

The American Heart Association recommends alcohol in moderation — less than or equal to one to two drinks per day for men and one drink per day for women. Here one drink is defined as 12 oz. of beer, 4 oz. of wine, 1.5 oz. of 80-proof spirits, or 1 oz. of 100-proof spirits.

The Dietary Guidelines for Americans 2015 – 2020 developed by the United States Department of Agriculture recommends a moderate consumption of alcohol. This equates to up to two standard drinks per day for men and one for women. Here, one standard drink is defined as 14 g of pure ethanol.

The Canadian Centre for Addiction and Mental Health guidelines recommend low-risk alcohol consumption — up to three drinks per day for men and two for women. One drink is defined as 12 oz. of 5 per cent beer, 5 oz. of 12 per cent wine, and 1.5 oz. of 40 per cent spirits.

Observational data around alcohol consumption and heart health suggests that a light-to-moderate intake, in regular amounts, appears to be healthy. However, when mathematical models have been applied to determine causation (an approach known as Mendelian randomization) the results have been mixed.

Some studies have found light-to-moderate drinking beneficial, while others have reported long-term alcohol consumption to be harmful for the heart.

For doctors, it is quite clear what to recommend to patients when it comes to diet, exercise and smoking. Given the inconsistencies in the findings relating to alcohol, and wine specifically, recommendations for consumption are less obvious.

For wine drinkers too, definitive answers on wine and health remain elusive. There is, however, immense research potential in this area for the future.

And as all the guidelines say, one or two glasses of red wine is ok. In relation to the question, a bottle of wine is 750ml and taking the WHO recommendation of a standard drink of wine being 140ml – that would mean each bottle has 5.4 standard drinks. So half a bottle (~2.7 glasses) each night is over the health recommendations.

This answer was adapted from an original article that was originally published on theconversation.com.

Yes, in any case, it is not recommendable to drink half bottle of wine every night. Wine is an alcoholic beverage that contains mostly alcohol and polyphenols. Polyphenols are bioactive compounds that have shown several health benefits. Alcohol consumption is always dangerous at high doses; although at moderate doses, it can also have protective effects, especially against coronary heart diseases (CHD). However, even at moderate doses, it is a well-known risk factor of stroke and many cancers (such as cancer of breast, upper digestive tract, colorectum and liver). Recommendations on alcohol consumption are based on epidemiological studies, showing J-shaped association curves with overall mortality. A methodological criticism of these studies is that the group of non-consumers is very heterogeneous, including sick people and former high drinkers. Moreover, the main cause of mortality some years ago was CHD; while nowadays, stroke and cancer are much more prevalent than before.

Each country has different recommendations for moderate alcohol consumption. For example, in Spain, the advice is not to drink more than 1-2 drinks and 2-3 drinks in women and men, respectively. One drink is equal to 10g of alcohol that is approximately 125mL of wine. However, most of the governments are reducing their recommendations up to 1 drink for women and up to 2 drinks in men during the entire day, not all at the same time. Moreover it is advised to consume the wine in a friendly and social atmosphere.