Aren’t you sick of hearing about wine and health?

There are two things that seem to be getting up people's noses regarding current health issues. The first is the SARS-CoV2 coronavirus and its associated Covid-19 disease. People are sick of hearing about it, and want the pandemic “to be over”, so that they can go back to “the way things were 2¾ years ago”. The second topic is that when we read something new about wine and health, it seems to contradict the previous thing we read — sometimes wine is good for us, and sometimes it is not.

Let’s talk about the second of these topics, here.

I have actually addressed different aspects of this particular topic three times before:

• Wine and health is never a simple topic
• Wine and health — why is there so much argument, pro and con?
• Why we are never going to know whether wine is good for us, or not

However, lately, the situation seems to be getting worse. There seem to be more and more reports appearing in the wine-industry media, and they seem to be getting more and more contradictory. Take these two, as recent examples of apparent contradiction with each other:

• New study links wine to better cognitive function in elderly
• Moderate drinking linked to brain changes and cognitive decline

How on earth is the general public supposed to make heads or tails of this state of affairs? (Let alone someone who has had a glass or two of wine!) I am a biologist, and I am supposed to understand all of this, but I only partly do.

The basic issue, it seems to me, is that these reports appear in the general media, repeating some technical report that originally appeared in the specialist medical media; and the general-media writers do not quite understand the topic they are writing about. So, they either repeat the contents of some press release, often taking the words out of context, or they quote selected so-called experts, or they try to explain things in their own words, thus perpetuating their own misunderstanding.

I am sure that many of you have already guessed what usually happens. The original medical experiment was conducted under specific circumstances, and any valid conclusions need to take into account the limitations of that work. Sadly, this is not taken into account in the general media, so that the conclusions are generalized way beyond what the original medical authors intended. This may make for exciting news reporting, but it does not lead to better understanding by the general public.

Take this report, from a generally reputable part of the US media, as a classic example:

Just five alcoholic drinks a week will age you — and mess up your DNA

The report’s author arrives at conclusions that exaggerate the data:

The study, published in Molecular Psychiatry, revealed that consuming alcohol in excess can wreak havoc on DNA by causing damage to telomeres — like protective caps at the ends of a chromosome — which could eventually lead to age-related diseases and the formation of cancer.

There were many such reports about this particular piece of medical work, around the world, some of them more moderate than others in their conclusions, and some referring to five large glasses of wine and others to seven pints of beer.

The original report (Alcohol consumption and telomere length: Mendelian randomization clarifies alcohol’s effects) was a descriptive (or observational) study, rather than an experimental one, trying to find correlations between chromosomal telomere length and alcohol consumption or alcohol use disorder. The authors conclude that there is:

a potential threshold relationship between alcohol and telomere length. Our findings indicate that alcohol consumption may shorten telomere length. There are implications for age-related diseases.

This is a long way short of the conclusions reached in the general media, don’t you think?

I am not alone, of course, in despairing of some parts of the wine media. Tom Wark, for example, divides writers into four groups: Advocates, provocateurs, cheerleaders and journalists. That pretty much covers the field; and only the latter can be relied upon for accurate reporting

For a primer on how to do things properly in the general media, you could consult: Three takeaways from “Finding the story in the data”. The takeaways are:

• Learn to write a story from the data
• Take time to learn about the data
• Become familiar with the data challenges.

It is the last one that so often is lacking in the wine media.

The basic issue is that pigs can fly — all you have to do is put them in an airplane, which is the same way we can fly. However, this does not happen very often, for pigs, if at all — so, there is a big difference between can and will. Consequently, this next heading doesn't actually say anything: Eating grapes can extend your life by 5 years and reduce Alzheimer’s risk, study says. It doesn't tell us what will happen, or what will probably happen, but only what can happen. That does not inform us at all. This title is no better: Can wine protect you from having a stroke? Of course it can, because most things can do so; none of them are very likely to do so, however.

This leads me to conclude that we probably shouldn’t pay too much attention to wine-media articles about health.