The truth about a glass of wine a day

An assessment of previous studies found the evidence in favour of moderate drinking to be riddled with flawed conclusions. Photo / Getty

It may be the news most of us don't want to hear. Despite countless stories about our favourite tipple having health benefits, and moderate drinking helping us live longer, a new study has sadly put those previous findings in doubt.

A team of scientists from the University of Victoria, Canada, have gone through 87 previous studies with a fine-toothed comb, and found the evidence in favour of moderate drinking to be riddled with flawed conclusions.

The Canadian research team found some of the previous studies drew from groups of alcohol abstainers who were in poor health due to former heavy drinking, or who did not drink due to exiting health issues. This created an abstainer bias that made all moderate drinkers look healthy in comparison.

Previous studies were found to be based on shaky, insignificant evidence and, according to Dr Tim Stockwell, director of UV's Centre for Addictions Research, linked moderate drinking to "an implausibly wide range' of health benefits."

In some of the previous research, moderate drinkers were shown to have lower risks of deafness and liver cirrhosis, as well as better overall health, than people that abstained from drinking.

Previous studies have defined moderate drinking as a couple of standard alcoholic drinks per day, which has now been labelled as a "biologically insignificant" amount. Meaning the moderate drinkers were not ingesting enough alcohol to have any impact on their health.

After the Canadian reasearchers corrected their studies to account for the abstainer biases, moderate drinkers were shown to have no advantage over those who shunned alcohol.

Only 13 of the 87 analysed studies avoided biasing the non-drinking group, and only 6 of the previous studies were considered high quality, the UV researchers discovered.

While the latest research did not look at the claim that certain types of alcohol had more health benefits than others, Dr Stockwell believes that line of thinking is false too.

"If that were the case, it would be unlikely that the alcohol content itself deserved the credit."