164 Million Obese Adults by 2030

Columbia University researcher Claire Wang, PhD, said at a news briefing in London that, about one in three adults in the U.S. are obese today. That figure will rise to half of American adults by 2030 if little is done to address the obesity epidemic, With those numbers will likely come higher rates of chronic diseases including diabetes, heart disease, arthritis, and some types of cancer.

Wang said in an interview that, "Our projections find that rising obesity is going to result in increases in many of these chronic diseases which are disabling and expensive to treat." "We have to act fast."

The briefing highlighted a special obesity edition of The Lancet, published online.

Wang says expenditures to treat obesity-related diseases will cost the U.S. health care system up to an extra $66 billion each year by 2030, if the projections become reality.

Wang and colleagues from Columbia University and England's University of Oxford constructed a mathematical model to project obesity rates in the U.S. and U.K. over the next two decades.

If, as they predict, 164 million Americans are obese by 2030, Wang says the health care burden will include:

• An additional 8 million cases of diabetes
• 6.8 million additional cases of heart disease and stroke
• Over 0.5 million cases of cancer

Those predictions don't have to come true. Even very modest weight reductions at the population level could have a dramatic -- and positive -- effect, Wang says.

For instance, the researchers calculate that just a 1% reduction in body mass index (BMI) at the population level would prevent as many as 2.4 million cases of diabetes and 1.7 million cases of heart disease and stroke.

Another report, from experts at the Harvard School of Public Health, shows that even though obesity has been rising globally for decades, efforts to address the problem have been lacking.

Researcher Steven L. Gortmaker, PhD, says a coordinated effort that includes the private sector is needed, but national governments must lead the effort, just as they have with tobacco control.

"No single government has really taken the lead on this issue and certainly in the United States an excise tax on sugar-sweetened beverages might not be particularly popular," he says, "but it could have a big impact on obesity rates and on the overall health of the population."

Wang, C. The Lancet, published online Aug. 27, 2011.