Here’s How Many Americans Are Now Obese
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Nearly 38 percent of U.S. adults are obese, according to the latest numbers from the Centers for Disease Control and Prevention.

Between 2013 and 2014, 37.7 percent of U.S. adults had a body mass index (BMI) of 30 or more, which is considered obese, according to a new CDC report. That's up from an obesity rate of 34.9 percent in 2011 to 2012. However, the researchers aren't sure if this increase represents a real change in the population, or sampling and chance played a role in the numbers.

What is clear is that obesity rates have increased over the last decade. From 1999 to 2014, the nation's obesity rate rose 24 percent among both adults and children, the report said. For the report, the researchers used data gathered during the National Health and Nutrition Examination Survey, which is conducted yearly by the CDC. The survey includes not only interviews with participants, but also physical examinations during which participants' height and weight are measured and used to calculate their BMI.

But obesity rates have been leveling off in recent years — from 2003 to 2014, the obesity rate among U.S. children ages 2 to 19 remained fairly stable, around 17 percent. [Lose Weight Smartly: 7 Little-Known Tricks That Shave Pounds]

Still, the prevalence of obesity remains higher than the government's public health goals — by 2020, the Department of Health and Human Services wants the obesity rate to be reduced to 30.5 percent among adults, and 14.5 percent among children, the report said. Obesity increases people's risk of a number of health conditions, including heart disease, stroke, Type 2 diabetes and certain cancers, the CDC says.

The new report also found that more women are obese than men: About 38 percent of women have a BMI over 30, compared with 34 percent of men. Obesity rates also differed among racial groups: From 2011 to 2014, obesity rates were lowest among Asian adults, at around 12 percent, and highest among black adults, at 48 percent, the report said.

The researchers noted that although BMI is a good indicator of whether a person is a healthy weight, it does not measure body fat directly. A person's health risks at any given BMI may vary depending on their race and ethnic groups. For example, some studies suggest that health risks among people of Asian descent may begin at a lower BMI compared with other racial groups, the researchers said.

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