By consumer affairs reporter Amy Bainbridge and Alex McDonald (Updated Mar 2016, 3:53pm)
The notion that moderate drinking can help you live a longer and healthier life is being challenged by new research released today.
- Researchers found studies linking moderate drinking to improved health were based on flawed science
- They found many of the studies were comparing moderate drinkers to abstainers
- The group of abstainers could include people who had given up alcohol due to poor health
A team of international researchers found that a number of studies linking one or two drinks per day with a range of health benefits were based on flawed science.
Curtin University's Tanya Chikritzhs, the principal investigator for the project, said her team analysed 87 studies and found most of them used questionable methodology.
Professor Chikritzhs said the main problem was how the studies compared drinkers with non-drinkers to gauge which group was healthier.
Moderate drinkers were more often than not being compared to abstainers, she said.
Professor Chikritzhs said the problem with that approach was that the group of abstainers included former drinkers, who had given up alcohol because of poor health.
"What these studies tend to do when they're trying to identify an abstainer group is to mix up in there a whole bunch of people who haven't drunk in the last 12 months with a whole bunch of people who used to drink 10 years ago, five years ago and so on," Professor Chikritzhs told the ABC.
"So essentially they set up a situation where an abstainer group looks as if they're in worse health than the drinker group.
"What we identified is when you account for this bias built into the methodologies of these studies, you actually don't find a protective effect of alcohol at all."
Professor Chikritzhs said there were other ways to look more accurately at the health impacts of drinking.
"What we found in our study is the best comparison group is not non-drinkers at all, but occasional drinkers, so these are people who drink in such small amounts that biologically alcohol could have no effect on their body in terms of protection," she said.
"What we actually found in terms of these occasional drinkers in terms of the longevity stakes — who lives longer — it's the occasional drinker who live the longest, so they outdo the people who are drinking at moderate levels."