…if you know where to draw the line
Amongst all the vexed and knotty questions of our time, one that keeps scientists foggy and perplexed is whether wine is good for you or not.
You may cynically wonder, of course, just how closely they are involved in the day to day experimental work on this issue, and how greatly that influences their level of fogginess. But that would be to under-estimate the complexity of the subject. So put the bottle down and focus.
Wine, specifically red wine, has been associated with various health benefits since the early 1990s, when the benefits of resveratrol and procyanidins in red wine were proposed as the reason that the wine-drinking French did not seem to suffer the levels of cardiovascular disease of other populations. These substances were thought to provide a protective effect on blood vessels, sufficient to reduce heart disease. Wine-drinkers cheered and raised their glasses, and more abstemious souls hurried to their health stores to stock up on red wine tablets (I know, but stranger things are sold, believe me).
The news got even better with the arrival of a 16-year long study that followed the stroke incidence of over 13,300 Danes. Compared with abstainers, those drinking wine weekly had a 34% reduced risk of stroke, and those drinking daily a 32% reduced risk. Letting your wine intake drop to merely monthly lowered your reduced risk to a meagre16%.  A global upsurge in demand followed, with wine producers delightedly contemplating the possibilities of labelling their stock as health food…
Beer and spirit manufacturers were unable to share the global glee, as no association was found between the intake of beer or spirits and the risk of stroke.
But before you ditch your whisky and check out the nearest vineyard, consider this. The Danish study was not controlled for confounding factors, and there are many, many potential confounding factors with this topic. For a bleary-eyed start, what about the social standing of different drinks? How about the fact that wine drinkers, especially a couple of decades ago when daily wine intake would not have been within the economic grasp of many social layers, might be better waged, with concomitantly better diets, better housing, and better health education? No one looked at the likelihood that regular red wine drinkers might be attending yoga classes and dining lightly on organic salad and salmon, thereby benefiting their cardiovascular health without any help from procyanidins.
The most recent contribution to this (red) hot topic appears in the form of a meta-analysis of 44 studies , and comes to a definite conclusion: it’s complicated…
A cardio-protective association (note the word ‘association’ – not as definite as ‘effect’) can be found between alcohol use and ischemic heart disease, but the benefits vary depending on many other factors.
- Are you female? In that case you can’t get away with anything more than a glass before the benefits start to disappear. Even with one drink per day the risk of breast cancer increases, although other health risks lessen.
- Do you binge drink once or more per month? (More than four drinks on one occasion for women or more than five for men.) This ruins the health benefits gained by light to moderate drinking.
- Are you predisposed to certain diseases due to your family genetics? Well this messes up the chances of drink protecting your health generally.
- Do you take Milk Thistle on a regular basis? Ok, this wasn’t mentioned in the study, but it’s the kind of factor that might be quite instrumental in improving outcomes – it protects liver cells from damage caused by alcohol , and has therefore gained a reputation as a good companion to a glass or two.
All of this explains why the study is hesitant about any conclusion other than moderate drinking is probably low risk, so long as women recognise that they can’t drink male quantities without harm.
It may well turn out that all daily low level red wine consumption can generally indicate is that you have sufficient spare cash to indulge in a crimson tipple, and sufficient self restraint to keep to one or two glasses. All of which might be an indicator of a generally healthy lifestyle. Cheers!
 Truelsen Dr T et al. Stroke 1998; 9: 2467-2472
 Michael Roerecke and Jürgen Rehm. Addiction 107: doi: 10.1111/j.1360-0443.2012.03780.x
 Saller R et al. Forsch Komplementmed. 2008 Feb;15 (1):9-20.