The benefits of boozing: Why are we obsessed with the health effects of alcohol?

Jeremy Laurance explains that the one thing we love as much as drinking is studies that say it's good for us

Glass half full: reaching a conclusion on the health benefits or dangers of alcohol is difficult (AFP/Getty)

Going out for a drink is the most popular social pastime in Britain. But is studying the habit the most popular scientific pastime too?

One could be forgiven for thinking so. Reports on the health effects of drinking seem to pop up as frequently as daffodils in spring. It is at least three decades since the debate over whether moderate drinking might actually be good for us began. How is it that the question is not settled yet?

The latest study, which has made headlines this week, found that consuming up to seven drinks a week lowered the risk of heart failure by 20 per cent among men and 16 per cent among women.

Good news for the drinks industry, then. But no, the study was not funded by it. The research was led by Professor Scott Solomon of Harvard Medical school and paid for by the US National Heart Lung and Blood Institute together with a couple of charitable foundations.

So why did they do it? Surprisingly, this is the first study of the link between alcohol and heart failure. We know a lot about the link between alcohol and heart attacks – moderate drinking is believed to protect us from them. But the researchers wanted to know if the same was true of heart failure – a condition in which the heart can no longer pump blood around the body as well as it used to, usually because the heart muscle has been damaged by injury or disease.

A subtle distinction, you might think, especially as the outcome suggests the protective effect of alcohol in heart attacks is similar in heart failure. Is this evidence of an unhealthy obsession among scientists with the health effects of alcohol?

It may of course be that it is the regular reporting of these studies in the media that gives the impression they are being conducted with great frequency. In my experience, few items excite news editors like a report that drinking is good for you.

Even for those who never prop up a bar, alcohol is the most widely used social lubricant, enjoyed by adults of all ages and both sexes, which helps us relax, reduces inhibitions and enhances enjoyment.

Of course we like to hear that it is good for us. But what excites scientists, goading them to perform more and more studies, is that the truth is complex. Yes, a drink a day may reduce the risk of heart disease and now of heart failure, too. But previous research has shown it increases the risk of bowel cancer. In women, it increases the risk of breast cancer.

Alcohol affects men differently from women – in part because women are smaller (on average), have less water in their bodies and metabolise it differently – and it affects older people differently from the young.

Weighing up these competing risks and reaching an overall conclusion on the health benefits or dangers of drinking is difficult. It also depends on individual risk. If you have a family history of heart disease, moderate drinking may be beneficial. If you have close relatives with bowel cancer you may want to be more circumspect.

What most studies agree on is that people who drink some alcohol live longer than those who drink none – teetotallers. Yet even this is not simple to interpret. It may be people who don't drink have a reason for being teetotal associated with their health – that they were alcoholic or had an illness that prevented them drinking. So their poorer health may account for their shorter lives – not their lack of drink.

Of one thing we can be sure – our continued interest in this area will keep the research grants coming. Another round, anyone?