New evidence on the relationship between moderate wine consumption and cardiovascular health

Light and moderate consumption of wine is associated with a lower risk of cardiovascular complications, according to a multicentre study led by researchers from the University of Barcelona, the Hospital Clínic and the August Pi i Sunyer Biomedical Research Institute (IDIBAPS), the Physiopathology of Obesity and Nutrition Networking Biomedical Research Centre (CIBEROBN) and the University of Navarra (UNAV). The study, published in the European Heart Journal, is based on the analysis of a biomarker of wine intake — specifically, tartaric acid, present in grapes. It was carried out in 1,232 participants in the PREDIMED project, a major scientific epidemiological study in nutrition on the effects of the Mediterranean diet on cardiovascular health.

According to the researchers, “there is no doubt that excessive alcohol consumption has serious health consequences. However, the effects of moderate and responsible wine consumption are still the subject of debate in the scientific community. The results of this study and others should help to place moderate wine consumption in its rightful place as an element of the Mediterranean diet, considered to be the healthiest in the world”.
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The principal authors of the study are the researcher Inés Domínguez, from the UB’s Faculty of Pharmacy and Food Sciences and the Nutrition and Food Safety Research Institute (INSA); Professor Ramon Estruch, from the UB’s Faculty of Medicine and Health Sciences and IDIBAPS; Rosa María Lamuela, professor and ICREA Academia, and member of INSA, and Professor Miguel Ángel Martínez, from the University of Navarra (UNAV); all members of CIBEROBN.

​​​​​​​Controversy over the effects of wine

Today, there is much controversy about the health effects of moderate consumption of alcoholic beverages in general and wine in particular. Ramon Estruch stresses that “part of this debate is due to conflicting results of studies that have pointed to a protective effect of wine, while others have found no such effect”. These differences could be explained by possible errors in wine consumption records. “Epidemiological studies assessing the role of wine in the rate of cardiovascular events are often based on self-reported information on wine consumption. These are reliable data, but subject to measurement errors due to inaccurate recall or biased perceptions about the social desirability of drinking alcoholic beverages”, he explains. In response to this problem, the researchers in this study measured wine consumption by means of food intake frequency surveys, which they confirmed with an objective biomarker: the concentration found in urine of tartaric acid, a molecule produced mainly in grapes and rarely synthesized by other plant species.

A reduction from 38% to 50%

Using this methodology, the study analysed wine consumption and cardiovascular outcomes in a cohort of PREDIMED patients. In total, 1,232 participants were evaluated, including 685 who had a cardiovascular event (cardiovascular death, myocardial infarction, stroke or heart failure) and 625 who were randomly selected.

Analysis of the data shows that light wine consumption (between one glass per week and less than half a glass per day) reduces the risk of having a cardiovascular complication by 38%, but this reduction reaches 50% when consumption is moderate (between half a glass and one glass per day). However, when consumption exceeds one drink per day, the protective effect disappears. The researchers also warn that “when we talk about moderate wine consumption, it is always with meals, never between meals”.

More studies to confirm the results
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Despite these conclusions, Inés Domínguez points out that “the observational design of the study limits the ability to establish causality”, and the experts point out that more research is needed: “The results of cohort studies should always be confirmed for greater certainty”. In this regard, they point to two potential avenues for action. The first would involve the design of randomized nutritional intervention studies, by randomly assigning participants to groups with different wine consumption. “These are very expensive studies to conduct. There is one underway now, but the results will still take four to five years”, they add. The second would be to study the mechanisms of these protective effects of wine on the cardiovascular system, such as research on the anti-inflammatory power of wine polyphenols — such as resveratrol and other phenolic compounds. “Knowing the mechanisms gives a lot of plausibility to the results of epidemiological cohort studies”, they conclude.​​​​