Is alcohol protection for the heart exaggerated?

In this week’s online New Zealand Medical Journal clinicians raise question marks over the protective effect for the heart of drinking moderate daily amounts of alcohol.

The writers of the viewpoint paper conclude that cardio-protection from alcohol is by no means certain and probably has been over emphasised in recent years.

"When viewed through the lens of two major early reviews in the mid-1980’s, then Sir Richard Dolls’s contributions in the mid 1990s, followed by two large meta-analyses a decade ago and two most recent overviews, the health giving properties of alcohol use becomes increasingly debateable," says one of the authors professor Doug Sellman.

Professor Sellman is Director of the National Addiction Centre at the University of Otago, Christchurch.

The writers raise the issue of the influence of the alcohol industry in some of the studies reviewed in relation to the exaggeration of positive effects on the heart and health generally.

They also point out that there are many other health downsides from heavy drinking, and that alcohol is now widely recognised as New Zealand’s most dangerous recreational drug.

The article stresses it is important to remember that the two major early reviews of the vast amount of literature on this subject came to opposite conclusions regarding alcohol’s protective effect on coronary heart disease (CHD). However, Sir Richard Doll’s sample of 34,000 UK doctors came down on the positive side or the argument.

The two meta-analyses a decade ago also equivocated. One said that alcohol reduces risks of CHD through changes in lipids and haemostatic factors, while the other said that the degree of protection from moderate drinking should be reconsidered and further research is needed.

Finally two recent overviews have also raised more doubts. An editorial in The Lancet said the benefit of light drinking have been over-estimated and warned of the health downsides of heavier drinking; increased blood pressure, risk of stroke, and risk of breast cancer increased by 9% for every additional standard drink.

"Essentially we believe that alcohol is still potentially a dangerous drug which can cause a range of acute and chronic health problems, so should not be promoted by anyone as a health tonic," say the writers of the article.

(Source: National Addiction Centre at the University of Otago, Christchurch: New Zealand Medical: Journal September 2009)