Interviews with key experts 17 February 2021

Wine and cancer – an interview with Prof. Ramon Estruch*

We have a vast amount of scientific evidence that indicates that moderate alcohol consumption protects against cardiovascular diseases. There is also numerous evidence that moderate consumption of alcohol in general, and especially wine in particular, reduces overall mortality (all-cause mortality), which is the main parameter to assess in health (individual and public health). However, the relationship between alcohol and cancer is more delicate, as there are many confounding factors that blur this relationship, especially studies with breast cancer in women.

The Trump’s administration (USA) prevented the development of the MATCH15 randomized study, which would have provided an answer to this and other aspects related to the beneficial or toxic effects of moderate alcohol consumption). In the absence of randomized clinical trials, the recommendations for alcohol consumption are based on the results of epidemiological studies in which many confounders involved in the alcohol-cancer relationship must be controlled very closely.

The most important is the dose of alcohol consumed per day. Moderate consumption should be different for men (up to two-three drinks a day – 30 g / d) and women (up to one drink a day – 15 g / d). Part of the apparent increased risk of cancer among light–moderate drinkers may be substantially due to underreporting of intake. Bad registration of the actual consumption of alcoholic beverages, especially in women. Several subjects report fewer doses than they actually drink.

Another important point is the pattern of alcohol consumption. It is not the same to consume a glass of wine a day (7 glasses a week) than 7 glasses in a single day – weekend). Binge drinkingBinge drinking (consuming rapidly four or more alcoholic drinks over a short period of time) has bee... is associated with a higher incidence of cancer. Many studies do not differentiate between the consumption pattern and the conclusions may be wrong.

It is also important to consider whether it is drunk with or without meals, as well as the dietary pattern. The effects are different if you eat a healthy diet (Mediterranean diet), with an adequate intake of vitamins (folic acid) than if it is not. We can go from “protection” to “induction”.

Finally, other lifestyle factors such as smoking (cancer induction) and physical exercise (protection) are also important. In most of the studies carried out these factors have not been taken into account, so it cannot be concluded that there is a cause-effect relationship between moderate consumption of alcoholic beverages (especially wine) and cancer.

Are there, according to scientific data, different  thresholds of “moderate consumption” for beer, wine, and spirits? If yes, what are they?

As the main toxic component of alcoholic beverages is alcohol (ethanol), the consumption threshold is based on the amount of alcohol.

The limits are:

  1. Up to 3 drinks a day (30 g/d) for men
  2. Up to 1-2 drinks a day (15 g/d) for women, independently of the type of alcoholic beverage consumed.

As far as the risk of cancer is at stake, are there any differences, based on scientific data, according to the way of consumption (ex: drinking with meals or between meals)?

As explained before, it is very important in the relationship between alcohol and cancer whether the alcoholic beverage is consumed or not with meals, but is also important the dietary quality of the meals. Mediterranean diet protects against cancer.

Are there scientific data that can evidence a difference of effects on health according to the type of alcoholic drink, for example between wine and spirits?

There are relatively few studies that differentiate the effects of the three types of alcoholic beverages (wine, beer and spirits) on cancer, but those that exist indicate that fermented beverages, especially wine, have a greater protective effect, mainly due to the non-alcoholic content , mainly polyphenols (resveratrol and others).

*Prof. Ramon Estruch, MD, PhD is Senior Consultant at the Internal Medicine Department of the Hospital Clinic (Barcelona) since 2002. He is also Associate Professor at the Barcelona University since 1996, Member of the Board of Directors of the CIBER Obesity and Nutrition, Institute of Health “Carlos III”, Government of Spain. For more information about his biography, click here.

The original interview was published in the Italian newspaper “Il corriere Vinicolo”, for more information, we invite you to click here.