Updated

Obesity costs some states as much as $15 billion a year, a new study says.

The researchers estimated how much each state spends on obesity-related medical costs each year.

The estimated costs range from $203 million in Wyoming to $15.2 billion in California. (Estimates are in 2009 dollars.)

"This study shows that the toll that obesity takes goes beyond impairing the health of individuals to imposing a major burden on the entire health care system," said study researcher Dr. Carolyn Clancy, director of the U.S. Agency for Healthcare Research and Quality. "Reducing the prevalence of obesity and its complications is an important priority for the nation and requires focused and constant attention."

The researchers used medical expenditure information from 2006 to generate an equation for the estimates.

The researchers also calculated the percentage of each state's medical costs that was due to obesity. They found obesity was responsible for at least10 percent of medical costs in Alabama, Alaska, Indiana, Louisiana, Michigan, Mississippi, Ohio, South Carolina, Tennessee and West Virginia. The lowest percentages were in Colorado and Hawaii.

The researchers said these estimates tended to be highest in the states with the highest rates of obesity. In 2006, West Virginia has the highest obesity rate, at 32.2 percent, while Colorado has the lowest, at 18.5 percent. By 2010, no state had a prevalence of obesity less than 20 percent, according to the Centers for Disease Control and Prevention (CDC).

"Across states, these estimates suggest that annual medical expenditures would be between 7.0 percent and 11.0 percent lower in the absence of obesity, the researchers wrote in a paper published June 16 in the journal Obesity.

The researchers noted that estimates within each state were subject to errors and influenced by many factors, so direct state-to-state comparisons were not reliable.

In a 2009 paper, the researchers estimated national costs attributable to obesity to be $147 billion.

Pass it on: Up to 11 percent of a state's medical costs are related to obesity, according to new estimates.

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