Events 13 April 2021

Wine and COVID-19: fake news or facts? Key takeaways

The WIC Scientific webinar on the topic of “Wine and COVID-19: fake news or facts?” took place on 2nd March 2020 and was presented by the Chair of the Wine Information Council, Prof. Nicolai Worm, German Nutritionist.

The webinar, which welcomed close to 100 participants, touched upon a number of important topics on the link between wine and COVID-19.

A summary of the key takeaways can be found hereunder.

1. ALCOHOLIC BEVERAGES AND THE IMMUNE FUNCTION

  • Consumption of alcoholic beverages can influence the immune system through multiple mechanisms, altering both innate and adaptive immune function. The innate immune response is the immediate responder part of the immune system and is non-specific to an invading pathogen, whereas the adaptive system is activated in response to a specific pathogen or antigen; it can recognize and immediately defend against a previously encountered pathogen, but it can also be activated by the innate immune response.[1] [2] [3]
  • The vast majority of research on alcohol and immune function and risk of infectious diseases is conducted on chronic heavy drinkers or people with alcohol use disorders.
  • Heavy drinkers are more susceptible to pneumonia and to bacterial and viral respiratory infections.[4]
  • Binge drinkingBinge drinking (consuming rapidly four or more alcoholic drinks over a short period of time) has bee... may also suppress immune response, but this response appears to be temporary.
  • In comparison, very few studies have been conducted among light and moderate drinkers.
  • Moderate drinking has been associated with either no risk or decreased risk of respiratory infections in some studies.[5]

⇒ To date there is no/insufficient evidence demonstrating an increased risk of infection associated with light or moderate drinking.

2. DOES WINE DRINKING (ALCOHOL / POLYPHENOLS) HELP FIGHT COVID-19?

In vitro/petri dish study:

  • In in-vitro studies, it was shown that polyphenols (flavanols, proanthocyanidins) in grapes and wine prevented the SARS-CoV-2 virus from attaching itself to human cells. This was only one study related to SARS-CoV-2 virus and it was an in-vitro study.[6]

Animal studies:

  • It was shown in animal studies that the spreading of the flu virus, NOT the SARS-CoV-2 virus, could be prevented by blocking its enzyme.[7]
  • Some wine phenolic compounds could prevent the multiplication of the Mers-virus (another corona virus but not SARS-CoV-2 virus), prevent the attachment or invasion in the host cell. [8]
  • FlavonoidsFlavonoids represent a structurally diverse group of polyphenolic bioactive compounds found in many ... in wine could stop the advancement of the flu and limit its symptoms. A possible mechanism may be that wine polyphenols influence the immune system through the gut microbiota.
  • Other possible mechanisms include that some (wine) polyphenols destroy the synthesis or composition of the genetic material or the shell of viruses.

⇒ However, whether these mechanism work against the Covid-19 virus in vivo in humans has not been studied/shown in any scientific study. More research is needed before any statement alleging that wine polyphenols can help fight COVID-19 can be made.

3. DOES WINE CONSUMPTION MAKE COVID-19 VACCINATION INEFFECTIVE

  • There is very limited research on light or moderate consumption of wine/alcoholic beverages and immune response to vaccines.
  • A small number of animal and human studies have examined the effect of alcohol consumption on the immune response following vaccination – however, no studies have been published so far on alcoholic beverages and response to a COVID-19 vaccine!
  • Some indication exists that moderate consumption of alcoholic beverages may assist the immune response to the vaccine, potentially through an anti-inflammatory effect of the wine polyphenols [9-10], however, there is an insufficient amount of research to form a conclusion.

Some basic research with wine polyphenols has been conducted in a petri dish but it is not possible to transfer these results to humans. Further animal and human studies need to be carried out.

[1] Molina, P. E., Happel, K. I., Zhang, P., Kolls, J. K., & Nelson, S. (2010). Focus on: Alcohol and the immune system. Alcohol Research and Health, 33(1-2), 97-108.
[2] Barr, T., Helms, C., Grant, K., & Messaoudi, I. (2016). Opposing effects of alcohol on the immune system. Progress in Neuro-Psychopharmacology and Biological Psychiatry, 65, 242-251.
[3] Romeo, J., Warnberg, J., Nova, E., Diaz, L. E., Gomez-Martinez, S., & Marcos, A. (2007). Moderate alcohol consumption and the immune system: A review. British Journal of Nutrition, 98, S111-S115 [back to text]

[4] Simou, E., Britton, J., & Leonardi-Bee, J. (2018). Alcohol and the risk of pneumonia: A systematic review and meta-analysis. BMJ Open, 8(8), e022344 [back to text]

[5] Ouchi, E., Niu, K., Kobayashi, Y., Guan, L., Momma, H., Guo, H., et al. (2012). Frequent alcohol drinking is associated with lower prevalence of self-reported common cold: a retrospective study. BMC Public Health, 12, 987 [back to text]

[6] Zhu, Y. and D.-Y. Xie (2020). “Docking Characterization and in vitro Inhibitory Activity of Flavan-3-ols and Dimeric Proanthocyanidins Against the Main Protease Activity of SARS-Cov-2.” Frontiers in Plant Science 11(1884). [back to text]

[7] Steed, A. L., et al. (2017). The microbial metabolite desaminotyrosine protects from influenza through type I interferon. Science 357(6350): 498-502. [back to text]

[8] Lin, S.-C., et al. (2017). Effective inhibition of MERS-CoV infection by resveratrol. BMC Infectious Diseases 17(1): 144. [back to text]

[9] Roseman, C., Truedsson, L., & Kapetanovic, M. C. (2012). The effect of smoking and alcohol consumption on markers of systemic inflammation, immunoglobulin levels and immune response following pneumococcal vaccination in patients with arthritis. Arthritis Research & Therapy, 14(4), R170. [back to text]

[10] Barr, T., Girke, T., Sureshchandra, S., Nguyen, C., Grant, K., & Messaoudi, I. (2016). Alcohol consumption modulates host defense in rhesus macaques by altering gene expression in circulating leukocytes. Journal of Immunology, 196(1), 182-195. [back to text]