Nov. 20, 2014 -- Nearly half the world's adults will be overweight or obese by 2030 if current trends continue, a new report by the McKinsey Global Institute predicts.

Currently, 2.1 billion people -- nearly one-third of the global population -- are overweight or obese, according to the institute, the Associated Press reported.

It also said the worldwide cost of obesity is $2 trillion a year, nearly as much a smoking or the combined costs of war, terrorism and armed violence.

The institute said there is no single or simple solution to overweight and obesity, but international disagreement on how to tackle the problem is hindering progress, the AP reported.