By his own admission, the 45-year-old advertising executive is a "drinker of some renown".

"I like getting drunk. I'm a big fan of it. Working as a media buyer there is booze everywhere. Any function you go to, every achievement, every win, every loss, it's all celebrated with booze. There's as much of it as you want and it's all free."

This weekly ritual, played out in workplaces and bars around the country, is not a new phenomenon.

But in recent times, Swifte has noticed a change at Friday night drinks.

"If the beer and chips come out at 4.30, by 5.30 all the kids under 30 are gone," he said.

"When we were starting out in our 20s if the office turned on booze you would literally sit around and drink until there was nothing left. Now the younger staff might have one beer or not drink at all.

"They just don't seem to have the same alcohol focus as the era when I grew up."

It's an observation that neatly encapsulates an emerging shift in Australia's drinking culture. An increasing number of young people are turning their back on alcohol. Yet, at the same time, older drinkers show no signs of slowing.

Experts warn the health burden for those in their 40s, 50s and 60s is starting to bite.

"This is almost an invisible group, partly because when people get older the pattern's been entrenched for a long time it's sort of seen as this is just what they do," said Professor Jon Currie, director of the National Centre for the Neurobiological Treatment of Addiction.

There is now concern that while attention has been focused on binge drinking among young people, their parents and grandparents have quietly been drinking themselves into oblivion.

"Binge drinking in older people can become more risky even than in younger people because of falls, confusion, cognitive impairment. Even the ability to tolerate moderate drinking becomes much less in the older population," Currie said.

"Their resilience is depleted and the damage that alcohol can do increases because there's less reserve in terms of brain capacity."

Generational changes in the way we drink can be seen in figures from the most recent Australian Institute of Health and Welfare's National Drug Strategy Household Survey – considered the most detailed snapshot of our nation's legal and illegal substance use.

Between 2004 and 2013 the number of 12 to 17 year olds abstaining from alcohol rose from 54 per cent to 72 per cent, while binge drinking among this age group dropped.

And, although 18 to 24 year olds are still the group most likely to binge drink, the trend is on a downwards curve.

In 2013, 57 per cent were drinking more than four drinks in one sitting at least once a month, compared to 47 per cent in 2004.

The proportion drinking at very high levels – 11 drinks or more – has dropped from 24 to 18 per cent.

Among 18 to 39 year olds, the number at risk of alcohol-related harm on a single occasion, or drinking in a way that puts them at long-term health risk, has continued to drop in the past five surveys, carried out every two to three years.

Conversely, over the past decade there has been little change in alcohol consumption in the over 40s and, in some older age groups, it is gradually increasing.

Among 40 to 49 year olds, 31 per cent are binge drinking once a month or more, compared with 29 per cent in 2004, and 27 per cent in 2001.

Those aged over 70 are the most likely to drink every day.

"Alcohol blunts all of life's little disappointments. As you get older there's more pain, there's arthritis, there's hips, there's aches, there's often depression, the finishing of careers, boredom and feeling of loss, impending mortality. All of these are immense drivers towards drinking," said Currie, former chairman of the committee that produced Australia's current alcohol guidelines.

Overall consumption dropping but risky drinking remains high

His concerns seem hard to reconcile with figures released in May by the Australian Bureau of Statistics, revealing alcohol consumption is at its lowest level in 50 years.

The alcohol industry trumpeted the 2013-14 data as proof Australia's binge drinking problem had been inflated by an over-zealous public health lobby.

But the picture is more nuanced than the figures suggest.

While overall we are drinking less than we have since the early 1960s, those in the prevention field say there is an emerging polarisation between those who are choosing not to drink at all and those who are consuming alcohol in acutely harmful ways.

A study published in the Medical Journal of Australia last week showed a major spike in alcohol-related ambulance call-outs in a decade in Victoria, with almost 13,000 in 2013-14 - an average of 45 a day – compared with 4000 in 2004-05.

One of its authors, Associate Professor Diana Egerton-Warburton, director of emergency medicine research at Monash Medical Centre, said that while young people remained over-represented in emergency departments, doctors were seeing casualties from all age groups.

"People often under-estimate how much they're drinking. So while there are a lot of people just making a bad decision on a night out and ending up with serious injuries and assaults as a result of alcohol harm, there are also terrible outcomes with chronic alcohol consumption."

Chris Raine, the 27-year-old chief executive of alcohol behaviour change program Hello Sunday Morning, said their research showed many fitness-conscious young people were giving up booze because it was more socially acceptable to embrace sobriety or moderate drinking.

While they are not the ones who make the headlines, many have heeded messages targeted towards them in a public health blitz that began in 2008 with then prime minister Kevin Rudd's national binge drinking strategy.

The shift is reflected in the changing demographics of those who sign up to the online program, which encourages users to take a break from drinking and chart their progress on social media and a smart-phone app.

In 2010 when the movement began, most were in their early 20s. Now the average age is 36.

Almost 70 per cent of Hello Sunday Morning's 50,000 users are aged between 40 and 64.

Most do not consider themselves alcoholics but are looking for help to change their relationship with alcohol after many decades of habitual and sometimes problematic drinking.

"The problem of changing 20, 30, 40 years of daily drinking for people in their 40s, 50s and beyond is much more nuanced and complicated than saying to young people to stop their binge drinking ways. Older people are often using alcohol to de-stress at the end of the day so they are afraid of how they'll cope without it," Raine said.

"The bulk of Australia's alcohol challenge is in your mum and dad's house behind closed doors but there's no sense of how you get policy or programs to help people make better choices in that age group."

John Rogerson, chief executive of the Australian Drug Foundation said government must invest in targeted programs for at-risk age groups, rather than taking a population approach to harm reduction.

Nick Swifte, who signed up to Hello Sunday Morning in January and gave up drinking for nearly a month, believes alcohol is part of Australia's cultural fabric.

"When I went to a few lunches and didn't drink people were like, 'Jesus, have you got cancer or something? Are you raising money?' It's just so much accepted that this is what we do.

"But I think if we've got no health complaints, we're relatively fit and as long as you have one or two days a week alcohol free you're OK."

jstark@fairfaxmedia.com.au

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