Life is likely to be long for Orin Murphy and Fyfe Atkins. The pair of six-week-olds have more chance of surpassing 100 years of age than anyone else who has lived before them.

But as our years grow longer, will the number of each person's healthy years be extended as well?

While some health experts have suggested this would be the first generation not to live to the age of their parents, data shows otherwise.

Despite obesity rates, diabetes conditions, lack of exercise and poor food choices, the emergence of public health improvements and scientific breakthroughs mean people are still going to keep on living, according to demographer Mark McCrindle.

"Almost regardless of personal choice we're living longer," Mr McCrindle said.

But there is a dark lining to this silver cloud.

While life expectancies had increased, the quality of life had not and the length of the healthy part of life had remained the same.

It is expected to put more pressure on national health services.

"We might be living longer but the quality of that life doesn't necessarily go along with the length of that life," Mr McCrindle said.

Edna Emery is one of Canberra's 48 centenarians. Despite living for so long, it hasn't stopped life's bumps and bruises from hurting her.

Ms Emery celebrated her 100th birthday in a Melbourne hospital with a broken arm, and soon after moved to the nation's capital.

She will turn 103 in three months and was not quite sure just how she had lived so long.

"I guess I've been very lucky with my health – I should have been dead years ago," said the woman who is older than Canberra.

Had Ms Emery been born about 40 years earlier she would have been one of only two centenarians in Canberra and of 203 in Australia.

Today she is one of 4252 people aged 100 years or over in Australia, according to the latest ABS statistics from a year ago.

Australia's ageing population will peak in about the middle of the century.

The latest intergenerational report from 2010 shows that by 2050 about 22.6 per cent of the population will be aged 65 and over.

At the same time it is predicted 5.1 per cent of the population will be older than 85.

Data from the Australian Bureau of Statistics shows that in the past 40 years, average life expectancy has risen 10 years.

Males born in 1971 could expect to live to about 68 and females to about 75.

Now men can anticipate living to 79.5 and women to 84.

By the middle of this century Orin Murphy and Fyfe Atkins are expected to be toasting their 38th birthdays.

For now Orin's mother Ilinka Budisic just wants him to experience what all mothers want for their children.

"I think it's always the same, you want them to be healthy and happy and to be a contributing member of society," she said.

Mother Amy Chin-Atkins said she aimed not to be an overprotective "helicopter parent" with six-week-old Fyfe, and the rest of her children Lian, 14, Kira, 10, and Sian, 4.

She wants her children to experience life for themselves without her hovering over their every move.

"Children have a very good sense of self preservation," Dr Chin-Atkins said.

While it may be hard to predict just how many centenarians there will be in Australia in the year 2112, Orin and Fyfe could well be two of them.