Does Red Wine Prevent COVID? Scientists Question Study Suggesting It Can

Experts have voiced concern over a study that concluded red wine is associated with a protective effect against COVID.

A Chinese study, published in journal Frontiers, investigated data, including self-reported alcohol consumption, on over 470,000 people held in the U.K. Biobank database. 16,559 of those people were confirmed to have tested positive for COVID.

Overall, it found an increased risk of developing COVID along with increased alcohol consumption. Studies have shown that long-term alcohol abuse can make someone more susceptible to infections. But it also suggested that certain types of alcohol seemed to be associated with a protective role against COVID while others increased the risk.

It found that COVID risk was 10 to 17 percent lower in red wine consumers compared to non-drinkers. On the other hand, it also found that consumers of beer and cider had between seven and 28 percent higher COVID risk compared with non-drinkers. "That is, a higher amount of beer and cider corresponds to a higher COVID-19 risk," the study stated.

It added that "the protective effect of red wine for COVID-19 was significant regardless of the frequency of alcohol intake, but it only played the protective effect when subjects consumed alcohol above or double above the guidelines."

The authors suggested that there are "several possible explanations for the findings," including comparatively high levels of polyphenols in red wine which "have antioxidant properties." They also suggested red wine could have the benefit of "activating proteins that prevent cell death."

The study stated that it only looked at baseline alcohol consumption and "we did not know about potential changes during the COVID-19 pandemic" and also that ingredients of alcohol sub-types were not considered.

While some news outlets have referred to the study as a "U.K. study" it was actually carried out by researchers at two hospitals in China before being published in the journal Frontiers in Nutrition on January 3rd, 2022.

Experts voice skepticism

Newsweek has spoken to multiple experts who have voiced skepticism about the study's findings.

Colin Angus is a senior research fellow at the Sheffield Alcohol Research Group at the University of Sheffield in the U.K. He has suggested that rather than red wine being the beneficial factor, it is the associated lifestyle and socioeconomic background of red wine drinkers that reduces the risk of COVID.

"The idea that the polyphenols in wine could reduce your risk of developing COVID by a staggering 17 percent is simply not credible," he told Newsweek. "All this study shows us is that the kinds of people who drink wine are also the kinds of people who have lower COVID risks because of many other factors unrelated to their wine drinking.

"Drinking a bottle of Bordeaux doesn't help stop you getting COVID, not being poor does."

Angus said that although the study authors took education level, employment status and a measure of deprivation called the Townsend Index into consideration, socioeconomic status is very complex and it is "notoriously difficult" to control for it.

"We know that risks of COVID infection are associated with many, many things, including geography, ability to work from home, health, whether you have had a COVID vaccination etc. For many of these things there is also a strong association with socioeconomic status," he added.

Angus' point was echoed by Edward Hutchinson, a senior lecturer at the Centre for Virus Research at the University of Glasgow. He told Newsweek that while the authors note that there will be "confounding factors," including socioeconomic factors, "it's not clear to me what steps they took to stop these clouding their conclusions."

Ian Jones, Professor of Virology at the University of Reading, said he was "not convinced" by the study, sharing concerns about confounding factors.

"The biggest risk is contact with the virus in the first place and I note that wine and fortified wine tend to be consumed in small groups or at home while beer and cider [is generally consumed] in more collective gatherings outside so exposure is different," he told Newsweek. "There are so many variables that even if the models attempt to compensate for them they fail. So, they did the study, they got what they got, but making sense of the outcome is up for anyone and I don't buy it."

The U.S. National Institute on Alcohol Abuse and Alcoholism states that drinking alcohol "does not prevent or treat coronavirus infection" and may actually impair immune system function.

Newsweek has contacted the study authors for comment.

Red wine benefits?

Both Jones and Angus also noted that the study is not unique; several papers have suggested that red wine has some health benefits and sometimes point to its antioxidant properties.

But Angus said there is "absolutely no robust evidence that wine is any better for you than any other type of alcohol," adding: "What these studies have instead found is that being well-off is good for you."

Some studies have shown that a polyphenol known as resveratrol can have beneficial impacts in small studies with mice. However, the resveratrol content in wine is so low that it is not possible to absorb the recommended therapeutic doses by drinking it, according to a 2016 study.

There have also been claims that red wine may help people avoid heart disease, but evidence for this has been described as weak by Dr. Kenneth Mukamal, an internist at Harvard-affiliated Beth Israel Deaconess Medical Center, and studies to this end have been observational rather than proving cause and effect, according to Harvard Medical School's health blog.

Red wine
A stock photo shows red wine being poured into a glass. Experts have voiced skepticism regarding a study that suggested red wine may have a preventative effect against COVID. NatashaPhoto/Getty