For the first time in history Mexico has surpassed the United States in becoming the world's most obese nation, says a new United Nations report.

Nearly a third (32.8 per cent) of Mexican adults aged 20 and older are considered obese, which narrowly surpasses the 31.8 per cent of obese American adults.

The U.N. report defines obesity as people whose body mass index (BMI) is 30 and above. And when taking into account those who are also overweight, about 70 per cent of Mexican adults fall into that category.

Luckily, Canada is not one of the top 25 most obese countries according to the report.

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Mexico's rapid urban development and rising income is being blamed for the increase in obese people. While citizens have greater access to food, they are dealing with the double burden of obesity and malnourishment in tandem. Furthermore, the epidemic disproportionately hits the poor and young.

“The same people who are malnourished are the ones who are becoming obese,” Dr. Abelardo Avila, a physician with Mexico's National Nutrition Institute, tells the Global Post. “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.”

Weight-related diabetes is the number one killer among Mexicans, with nearly one of every six Mexican adults suffering from the disease.

The growth of industrialized agricultural production has meant rural families abandon their farms and take on urban jobs that are less physically laborious, all the while increasing their consumption of processed foods.

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“The result is that for many Mexicans, particularly in urban areas or in the northern states, switching to healthier diets is becoming increasingly difficult,” U.N. expert Olivier de Shutter says in a report on Mexican agriculture and nutrition issued two years ago.

The current U.N. report comes just before the release of new study showing that obesity levels are continuing to rise in the U.S. and worldwide. The good news is that the U.S. is simultaneously seeing a rapid increase in the amount of citizens who exercise.

Prevalence of obesity among adults in developed countries (% obese)

Source: United Nations Food and Agricultural Organization's 2013 State of Food and Agriculture Report

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