Australia is ranked among the fattest countries in the world. There has been a steady rise in the number of obese and overweight people over the past 30 years, around one in five adults is currently obese or overweight. According to the 2011-2012 statistics, around 70 per cent of males and 56 per cent of females aged 18 or above were obese or overweight.

"Prevalence of overweight and obesity in adults aged 18 years and over has continued to rise to 63.4 per cent in 2011-12 from 61.2 percent in 2007-08 and 56.3 per cent in 1995," according to the findings of Australian Bureau of Statistics (ABS).

In Australia, the wellbeing cost of obesity has risen by nearly $50 billion a year since 2005-06, Sydney Morning Herald reported in March, 2013.

COAG Reform Council finds the situation alarming. "It's concerning to see that so many Australians are overweight or obese but the fact that the situation is getting worse suggests that it needs urgent attention from our governments to prevent flow-on effects across the system," John Brumby, chairman of COAG, had said in May 2013.

There are a "myriad of factors" that is driving Australia's epidemic, according to a report by department of health, Government of South Australia. The factors include the food industry boom that has increased the consumption of "high in energy, protein and fat and low in complex carbohydrate" diet. In the last two decades, the family structure and lifestyle have changed, and also Australians are putting in long hours at work, leading to increasing demand for convenience food that is low on nutritional value.

The report by department of Heath, Government of South Australia also suggests that "people are losing control over the composition of the foods they eat, with this often left in the hands of the food manufacturer," which is a major factor for the rising number of overweight and obese people in Australia.

A group of scientists, however, would like to disagree. They have put the blame on a gene called FTO for causing obesity. BBC reports that a study, published in The Journal of Clinical Investigation, finds that FTO alters the level of the hunger hormones, ghrelin and also makes junk food more tempting.

Obesity has a strong family link and it is highly likely that some Australians' genetic codes are driving the obesity epidemic. The researchers at the University College London, tested two groups of men and discovered that men with fatty genes found pictures of high-fat foods more appealing than the men with no fatty genes, BBC reports.

Our advice: blame the obesity on genes but change the lifestyle. And, don't let the visuals of beguiling junk food on T.V make you consume low on nutritional value food. Eat healthy and exercise. Go for a cycle ride!