Dr Danny Donaghy is professor of dairy systems at Massey University and a specialist in pasture agronomy and physiology.
An extensive study of the medical records of 473,957 people tracked alcohol consumption and Covid infection during the pandemic. While noting that "adverse effects of alcohol consumption have been widely documented, the observed reationships between alcohol consumption and diseases are often non-linear, with low-to-moderate alcohol consumption being protective and heavy alcohol consumption being harmful". The study found that compared with non-drinkers, the Covid-19 risk was 10-17% lower in red wine consumers and 7-8% lower in white wine and Champagne drinkers.
Beer and cider drinkers, on the other hand, had a 28% increased risk of Covid infection.
The beneficial effect could be the result of polyphenols, which are higher in red wine than in white wine. "Red wine provides additional benefits to other alcoholic beverages, probably due to its higher polyphenolic content, by decreasing blood pressure, inhibiting the oxidation of low-density lipoprotein particles and other favourable effects on the cellular redox state, improving endothelial function, inhibiting platelet aggregation, reducing inflammation and cell adhesion, and activating proteins that prevent cell death," noted the study.
Most of us will struggle to understand that scientific explanation. However, the bottom line seems to be that wine drinkers, particularly red wine drinkers, may gain some protection from Covid. They should of course stay within the recommended guidelines of alcohol consumption which are two standard drinks a day for women and no more than 10 standard drinks a week, and three standard drinks a day for men and no more than 15 standard drinks a week.