The United States no longer holds the title of the world’s most populous, obese nation; that designation has been passed on to Mexico.

According to a new report from the United Nations, nearly 70 percent of Mexican adults are overweight, and childhood obesity in the country has tripled within the past decade, Medical Daily reported. One-third of Mexican teenagers are also obese, and experts believe that four out of every five obese children will remain overweight for the rest of their lives.

Overall, 32.8 percent of Mexican adults are considered obese, compared to 31.8 percent of adults in the United States. Nearly 70,000 deaths in Mexico each year are caused by weight-related diabetes, and more than 400,000 new cases of diabetes are diagnosed annually.

Experts believe the rise in Mexico’s obesity rates has to do with the continuously growing gap between the country’s classes, as 50 percent of the population currently lives below the poverty line. According to Medical Daily, healthy diets are becoming less affordable, prompting individuals with low incomes to consume more unhealthy foods, such as fried foods and soda.

One researcher also believes the increase can be attributed to more Mexicans moving from rural to urban areas, where food prices are much higher and sedentary lifestyles are easier.

“The result is that for many Mexicans, particularly in urban areas or in northern states, switching to healthier diets is becoming increasingly difficult," UN expert Olivier de Shutter wrote in a report on Mexican agriculture and nutrition.

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