NEW YORK (MainStreet) — Income inequality apparently breeds health disparity: in the U.S., you're either broke and fat or rich and fit. Well more than one quarter or Americans (27.7%) are obese, the most ever since Gallup and Healthways began tracking obesity in 2008. And severe weight problems are divided along economic lines, according to the research.

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Nearly one-third of adults (31.9%) with incomes less than $36,000 are obese, compared to only 23.1% of high-income Americans (those earning $90,000 or more annually). Black Americans are the most likely (35.5%) to be severely overweight among all demographic groups, as has historically been the case. Meanwhile, young adults aged 18 to 29 years (17.0%) are least likely to be obese.

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Senior citizens are still struggling to remain fit and notched the highest increase in obesity among all subgroups considered in the research, with 27.9% of adults 65 and older considered severely overweight – a gain of 1.6 points from one year ago.

"While it is difficult to identify long-term trends from short-term data, these data suggest, at best, no retreat in the obesity epidemic and, at worst, a deterioration," says Janna Lacatell, Healthways lifestyle solutions director. "Given that obesity leads to higher rates of serious health conditions like diabetes and hypertension, and has been shown to cause disease onset at younger ages, this is a significant public health concern. Further, populations that have a disproportionately high obesity rate, such as African Americans and southerners, also have disproportionately higher diabetes rates."

A previous Gallup study identified Mississippi and West Virginia as the states with the most obese citizens while Montana and Colorado had the least. Three communities in Colorado -- Boulder, Fort Collins-Loveland, and Denver-Aurora -- were among the ten communities in the nation with the lowest obesity rates.

Huntington-Ashland, West Virginia has been among the ten most obese communities every year since 2008.

The survey asked respondents to self-report their height and weight in order to calculate body mass index (BMI) scores. Since 2008, nearly two-thirds of Americans have had BMIs higher than are recommended, while roughly 35% have been in the "normal weight" category. Individual BMI values of 30 or above are classified as "obese," 25 to 29.9 are "overweight," 18.5 to 24.9 are "normal weight," and 18.4 or less are "underweight."

More than one-third (35.3%) of Americans are considered overweight, while just 2.1% of the adult population is categorized as underweight.

--Written by Hal M. Bundrick for MainStreet