A new report by the McKinsey Global Institute released Thursday that the global cost of obesity has risen to $2 trillion annually — nearly as much as smoking or the combined impact of armed violence, war and terrorism.

The report focused on the economics of obesity, putting it among the top three social problems generated by human beings. It puts its impact at 2.8 per cent of global gross domestic product.

"Obesity isn't just a health issue," one of the report's authors, Richard Dobbs, said in a podcast. "But it's a major economic and business challenge."

The company says 2.1 billion people — about 30 per cent of the global population — are overweight or obese and that about 15 per cent of health-care costs in developed economies are driven by it.

In emerging markets, as countries get richer, the rate of obesity rises to the same level as that found in more developed countries. The report offers the stark prediction that nearly half of the world's adult population will be overweight or obese by 2030 should present trends continue.

The report's authors argue that efforts to deal with obesity have been piecemeal until now, and that a systemic response is needed.

McKinsey says there's no single or simple solution to the problem, but global disagreement on how to move forward is hurting progress. The analysis is meant to offer a starting point on the elements of a possible strategy.

"We see our work on a potential program to address obesity as the equivalent of the maps used by 16th-century navigators," McKinsey said in its report. "Some islands were missing and some continents misshapen in these maps, but they were still helpful to the sailors of that era."

The report recommends 16 measures to collectively lower obesity rates, such as portion control, changing marketing practices, and restructuring urban and education environments to encourage physical activity.

At the UN Food and Agriculture Organization on Thursday, Pope Francis condemned a "paradox of plenty," where enough food is produced globally for everyone but not everyone has enough to eat.

Currently, a third of the world's population suffers from nutritional deficiencies of the sort that caused 45 per cent of all child deaths in 2013, according to UN data. At the same time, 42 million children under age five are overweight and some 500 million adults were obese in 2010.

The papal speech came a day after more than 170 countries at the UN nutrition conference adopted new voluntary guidelines to prevent malnutrition, promote healthy diets and reduce levels of obesity around the globe.

Between 1985 and 2011, the prevalence of adult obesity in Canada increased from 6.1 per cent to 18.3 per cent, based on self-reported heights and weights, according to a study published earlier this year in CMAJ Open.

The latest research suggests obesity costs Canada's health system $6 billion a year.

Canada generally invests in treating obesity rather than treating its causes, said Ian Janssen of the Queen's University School of Kinesiology and Health Studies in Kingston, Ont.