Talking about obesity can be a delicate matter. But a McKinsey Global Institute report argues that unless world thought leaders address the issue now in a straightforward manner, obesity has the potential to extract a toll on humanity to the magnitude of that taken by smoking tobacco, violence and warmongering.

The McKinsey report estimated the global cost of obesity at $2 trillion annually.

 "More than 2.1 billion people — nearly 30 percent of the global population — are overweight or obese. That's almost two-and-a-half times the number of adults and children who are undernourished. Obesity is responsible for about 5 percent of all deaths a year worldwide, and its global economic impact amounts to roughly $2 trillion annually, or 2.8 percent of global GDP — nearly equivalent to the global impact of smoking or of armed violence, war, and terrorism," McKinsey said. "If the prevalence of obesity continues on its current trajectory, almost half of the world's adult population will be overweight or obese by 2030."