Since 1980, obesity rates in the developed countries of the world have risen significantly. In the United States, obesity statistics indicate that almost one in every three people is medically obese. Other countries have also experienced significant increases in obesity rates over three decades. Obesity is defined by a body mass index greater than 30. A BMI between 25 and 29.9 is considered overweight, while a healthy BMI range is between 18 and 24.9. BMI is not always accurate, however -- especially in instances of people with large frames and lots of muscle mass -- and some in the medical community don't recommend its use to determine obesity.
According to a book published in September 2010 by the Organization for Economic Co-operation and Development, or OECD, obesity rates in the U.S. and Mexico are the highest in the world. Medical News Today reports that 2010 data indicate that 28 percent of all U.S. residents are medically classified as obese, while 30 percent of Mexicans are obese. A person whose weight is at least 20 percent higher than the upper limit of the healthy range is considered obese.
Comparison with Other Countries
Mexico's 2010 obesity rate is the highest in the world; the U.S. ranks second. Other countries with obesity rates between 20 percent and 27 percent include New Zealand (27 percent), Australia and the United Kingdom (25 percent), Canada (24 percent), Ireland (23 percent), Chile (22 percent), Iceland and Luxembourg (20 percent each). Countries with the lowest overall obesity rates include Japan (3 percent), Korea (4 percent), Switzerland (8 percent), Italy, Norway and Sweden (10 percent each. In all of the countries examined by the OECD, the average obesity rate was 16 percent.
Causes of obesity in the U.S. and other countries include the typical national diet and nutritional profile and also lifestyle trends in each country. An article in the August 2004 issue of the American Journal of Preventive Medicine indicates that community design, physical activity levels and levels of car use all affect obesity rates. Many American cities and towns were built in the automobile era, resulting in fewer walkable communities in the U.S. than in countries with lower obesity rates, such as Italy or France.
Obesity puts you at risk for many health problems and diseases, according to Medical News Today. Obesity increases your risk of heart disease, osteoarthritis, high blood pressure, high cholesterol, respiratory issues, stroke, Type 2 diabetes and stroke. It's estimated that an obese person will, on average, live eight to 10 years less than a non-obese person. A high obesity rate in the population of a country increases health care costs significantly.