A small drop in the alcohol content of beer or other drinks may reduce its harmful effects such as injuries or deaths due to accidents, as well as alcohol-related chronic diseases like cancer.
Alcohol accounts for significant death and disability worldwide. According to the World Health Organisation (WHO), nearly one-quarter of deaths among those aged 20-39 can be attributed to alcohol, researchers said.
"The idea is that a small reduction in alcohol - such as beer with four per cent ethanol content versus six per cent - would reduce alcohol intake per drinker even if the same overall amount of beverage is consumed," said Jurgen Rehm, from the Centre for Addiction and Mental Health in Canada.
A decrease in ethanol, the most harmful ingredient in alcoholic beverages, would be expected to lead to lower blood alcohol levels in drinkers, researchers said. This could reduce immediate harms such as injuries or accidents, as well as alcohol-related chronic diseases that develop over time, such as liver cirrhosis or cancer.
A key concern is that drinkers would notice the difference in alcohol content, and consume more to compensate or switch to other beverages with more alcohol. "We know from experiments that consumers can't distinguish between beers of different strengths," said Rehm.
In one study set at three fraternity parties, the amount party-goers drank did not differ with weaker versus stronger drinks. In another study, participants were given lower- and higher-strength beer on two different occasions, and most did not report differences in how they felt after these sessions.
In both studies, participants had a significantly lower blood alcohol concentration with lower-alcohol drinks. The researchers also found some studies on the broader, societal impact.
The Northern Territories of Australia levied a tax on alcohol with more than three per cent ethanol, which led to greater availability of lower-strength beer. This policy change resulted in fewer alcohol-related deaths, but also took place in combination with educational efforts, greater controls on availability and new treatment services.
Another approach to reducing alcohol harms identified would be offering alcohol-free drinks as a cheaper alternative in bars or restaurants. The drawback is that not only does it require drinkers to choose this option, but there is limited evidence that it affects drinking levels or alcohol-related harms.
Whether lower-strength alcohol can reduce the burden of alcohol harms will depend on how any measure is implemented and evaluated, researchers said. However, the evidence suggests it is worth considering as a "win-win" for public health efforts and alcohol producers.
The study was published in the journal Lancet Gastroenterology and Hepatology.
