The cost of obesity is so high that nearly any systematic approach to reining it in would be cost effective, according to the global consulting firm McKinsey.

Nearly 30 percent of people in the world are obese, causing a health crisis that costs the world economy $2 trillion, according to a new report from McKinsey Global Institute. The report finds that the global price for obesity is almost as large as the one imposed by smoking or armed conflict.

Treating obesity directly accounts for 2 to 7 percent of healthcare spending in industrialized countries. When related diseases, such as type 2 diabetes, are included, obesity accounts for as much as 20 percent of healthcare costs.

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McKinsey, a global consulting firm, also points to evidence that worker productivity is diminished by the obesity epidemic.

As countries expand their economies, they also increase their waistlines, according to the findings. By 2030, almost half of the world’s population will be obese if current trends continue.

Already, more people face health problems caused by too many calories than from too few. The number of obese people is two and a half times the number of undernourished people around the world.

Obesity accounts for 5 in 100 deaths worldwide.

The McKinsey report contends that it will take a “portfolio” of interventions to roll back the trend. However, most interventions, ranging from reducing the availability of soda to expanding gastric bypass surgery, are cost-effective for society.

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The report analyzed existing data on the effectiveness of a number of credible public health programs to combat obesity, such as limiting advertising for foods high in fat or sugar, workplace wellness programs, and prescription drugs. 

If 60 percent of these interventions were put into place, 1 in 5 overweight people could be returned to a healthy weight. However, industry, doctors, and government agencies would have to work together for the efforts to succeed.