Professor Andrea Maier helps people live longer and healthier life spans and says Australians need to increase their day-to-day activity levels.

Making daily life "more difficult" is what Australians need to do to ensure they live well in old age.

Professor Andrea Maier from Royal Melbourne Hospital and University of Melbourne helps people to live longer and healthier life spans.

The professional fellow of aged care says living longer is relatively easy, but living healthy life spans requires effort.

With apps that allow you to do the weekly grocery shop online "it's not very easy" to be physically active in this society, acknowledges Prof Maier.

"But you just have to make your life a little bit more difficult - include your physical exercise in the daily living," Prof Maier told AAP.

Life expectancy has increased across the globe, and in South Korea it's creeping towards 90.

According to new life expectancy projections, published in The Lancet, Australian boys born in 2030 can expect to live to 84, four years longer than those born in 2010.

Girls born in 2030 can expect to live until they are 87.5.

Despite living longer lives we are "growing old as patients" because of health behaviour, Prof Maier told AAP.

"It's the diet, it is the physical inactivity, it's the smoking," she said.

Research shows people are being diagnosed with diseases younger.

A decade ago the average age the first incidence of disease was typically reported, says Prof Maier, was about 50. Now it's around the age of 45.

"We just diminish the potency of our health care system to live longer in a unhealthier way," said Prof Maier.

The good news is behavioural changes that have an impact can be made even at the age of 50 and 60.

It starts with being more active, both cognitively and physically.

The excuse that physical activity costs time and money is not good enough, Prof Maier says.

"We just should go back to our roots where we increase the physical exercise in the normal daily life, so make life a little more physically exciting" she said.

TIPS TO TAKE ADVANTAGE OF DAILY LIVING

• Brush your teeth on one leg - this increases your balance and strength and therefore reducing your risk of falls later in life.
• Use a small plate - this will help reduce over-eating and aid weight loss and therefore reduce disease risk caused by obesity.
• Walk down the street (to get the milk).