The study by the Research Triangle Institute in Research Triangle Park, N.C., and the Centers for Disease Control and Prevention in Atlanta reported the proportion of all annual medical costs that are due to obesity increased from 6.5 percent in 1998 to 9.1 percent in 2006.
The amount includes payment by Medicare, Medicaid and private insurers as well as prescription drug spending. Overall, people who are obese spent $1,429, or 42 percent, more for medical care in 2006 than did people of normal weight. The estimates were compiled using national data that compare medical expenses for normal weight and obese persons, the report said.
"It is critical that we take effective steps to contain and reduce the enormous burden of obesity on our nation," Dr. Thomas Frieden, CDC director, said in a statement.
The study appears online in the journal Health Affairs and was released at CDC's Weight of the Nation conference in Washington.