A person is considered obese if they have a body mass index of over 30. Approximately 3.4 million adults succumb to death every year as a result of being obese or overweight. The rise in obesity has been gradual but constant across the globe, with latest estimates suggesting that the world has over a billion obese people that is double the rate that existed 20 years ago. The 10 most obese countries in the world are:

Correlation With Economics And Obesity
The most obese countries in the world are not necessarily the richest or the most developed ones. Countries with smaller economies, such as Nauru, Palau, Marshall Islands, Tuvalu, and Tonga have made it to the top 5.
As per the World Health Organization, food scarcity and its rising prices are also responsible for obesity in underdeveloped or developing nations, where the public finds it difficult to eat a balanced, healthy diet. For these people, the option is filling up on empty calories with junk or fried food.
Pacific Island And Middle East Nations Are Most Obese

Participants of a walk against Diabetes and for general fitness around Nauru airport. Image credit: Lorrie Graham/AusAID,/Wikimedia.org
As aforementioned, topping the list of the world's most obese countries are small Pacific Island nations such as Nauru, Palau, and Tuvalu, to name a few. Approximately half of the population of these countries are obese. The reason is that almost all of the food consumed in these island nations are imported and therefore expensive. However, fast-food chains offer a cheaper and more convenient alternative.
The Pacific island nations are closely followed by a string of Middle Eastern nations – Kuwait, Jordan, Saudi Arabia, Qatar, and Libya. Around three-quarters of the population in these countries is overweight and well over a third is considered obese. With scorching hot temperatures of up to 40 degree Celsius, regular ‘natural’ exercise such as walking is not common in these countries. Coupled with an increasing embrace for western fast-food restaurants in recent years, the waistlines in the Middle East have soared. Traditionally, the people here often share large community platters, making it difficult to keep track of portion size.
Adult Obesity in the United States
The United States is the world's 10th most obese country and the most obese country in North America with 36.2% of its population having a body mass index of over 30.0. Nearly 78 million adults and 13 million children in the United States deal with the health and emotional effects of obesity every day. According to the CDC, an average adult is 26 pounds heavier now than in the 1950s.
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