What's really pushing up obesity in US

The obesity epidemic in the US has opened a pandora's box. An analysis has revealed that commonly-held assumptions about the causes that have pushed up the rates of obesity are mostly wrong.

Contrary to popular belief, people are exercising more today, have more leisure time and better access to fresh, affordable food - including fruits and vegetables - than they did in past decades, the study said.

While troubling disparities exist among various groups, most economic, educational, and racial or ethnic groups have seen their obesity levels rise at similar rates since the mid-1980s.

"The gap between groups is secondary to the increase that all groups experience over time," said Ruopeng An, a kinesiology and community health professor at University of Illinois, US.

So a reversal of the obesity epidemic would need universal intuitions rather than a focus on certain groups, he added.

So what is it that is making the waistlines larger in the US?

The easy availability of food could be one of the factors.

"Overall, food is more accessible and affordable than ever in the US, and this may be an important factor in the dramatic rise in obesity," An noted.