Mexico has overtaken the United States as the fattest country on this half of the globe, CBS News reports.

With a 32.8 percent adult obesity rate, Mexico just inches past the 31.8 percent obesity rate in the United States, according to a study released last month by the United Nations Food and Agricultural Organization.

That makes Mexico the most obese country in the hemisphere and one of the fattest countries on the planet. According to the FAOs data, which dates from 2008, several Pacific Island countries and territories have even higher obesity rates. Nauru (71.1 percent), the Cook Islands (64.1 percent) and the Marshall Islands (46.5 percent) all boast obesity rates well above those found in either Mexico or the United States.

The problems caused by obesity are causing a public health crisis in Mexico, with children growing fatter and adults increasingly dying from heart disease and diabetes.

For Mexico, theres something of a silver lining to the terrible news that its people have surpassed Americans as the most obese in the hemisphere. That feat is made possible by the sedentary lifestyle afforded to an increasingly wealthy, urban population.

But on balance, its basically just bad news. Less manual labor and more convenience arent the only things that keep Mexico plodding along the path toward obesity -- it's also terrible eating habits, paradoxically fostered in part by low incomes.

"The same people who are malnourished are the ones who are becoming obese," physician Abelardo Avila with Mexico's National Nutrition Institute told CBS News. "In the poor classes we have obese parents and malnourished children. The worst thing is the children are becoming programmed for obesity. It's a very serious epidemic."

Barry Popkin, an obesity expert at the University of North Carolina, attributes much of the spike in Mexican obesity to increased consumption of cheap sugary drinks and mass-marketed snack foods (the type of things that got Americans fat as well), which have displaced home-cooked meals, along with fresh fruits and vegetables.

As Al Jazeera put it in an article published in April:

The speed at which Mexicans have made the change from a diet dominated by maize and beans to one that bursts at the seams with processed fats and sugars poses one of the greatest challenges to public health officials.