As a nation, we eat far too many processed foods and not nearly enough fruit and vegetables.

And, while alcohol consumption has, admittedly, declined over the years, we remain very much a country of drinkers.

Worryingly, roughly a third of our energy intake comes from discretionary foods such as cakes, biscuits, chocolate, sweets, pastries, potato chips, soft drinks and alcohol.

Most of the population knows the key to a healthy lifestyle lies in doing plenty of exercise and eating an abundance of fresh, whole foods.

Yet why do so many people struggle with this?

The Australian Institute of Health and Welfare’s recent “Nutrition Across the Life Stages” report indicates that most children get a decent start in life when it comes to exercise and diet.

Children aged 2 to 3 years do 75 per cent of the recommended physical activity each day and 22 per cent are overweight or obese, according to the report.

But by the time they are in the 14 to 18 age bracket, just 16 per cent exercise enough and 30 per cent are overweight or obese.

In adulthood it seems we pick up better exercise habits, but poor eating negates that – namely an increased alcohol intake.

At ages 19 to 30 there are 55 per cent who exercise enough but 47 per cent are overweight or obese. It is a steady decline in both categories from there until we hit 71 years or more.

Even with exercise, if you don’t eat properly, you won’t keep the weight off. This is a familiar warning that has been repeatedly ignored. 

But the reform starts with ourselves – with good food choices and carving out time to look after ourselves.

Our own example sets the model for all those who come after.

Without it, in an age of surfeit and ease, where poor food is cheapest the outlook is bleak.

National leadership may have failed on this but we can still choose. Our longevity depends on it.