(HealthDay)—Obese American adults die an average of almost four years earlier than those with normal weight, and middle-aged obese adults face the highest risk of an early death, a new study suggests.
One expert wasn't surprised by the findings.
"As we are watching the epidemic of obesity grow, we need to understand the huge implications—not just on chronic illness, but also the effect on life expectancy," said Dr. Suzanne Steinbaum, a preventive cardiologist at Lenox Hill Hospital in New York City.
"It is time that we treat obesity as a medical illness, because, as with other chronic diseases, it causes premature death," said Steinbaum, who was not involved in the study.
In the study, researchers Dr. Luisa Borrell and Lalitha Samuel of the City University of New York reviewed data collected by the U.S. National Health and Nutrition Examination survey between 1988 and 1994, as well as national death statistics through the year 2006.
They found that obesity was associated with at least a 20 percent increased risk of death from all causes or from heart disease. Overall, obese adults died 3.7 years earlier from all causes and 1.7 years earlier from heart disease, compared with normal-weight adults.
The study found the risk to be highest among obese adults aged 45 to 64, who died 7.1 years earlier from all causes and up to 12.8 years earlier from heart disease.
Kelly Hogan is a clinical dietitian at Mount Sinai Hospital in New York City. She said the health impact of the obesity epidemic in the United States might be even greater in the future.
"Given the prevalence of obesity among children and young adults, early intervention is absolutely essential in order to prevent this trend from increasing exponentially as these populations continue to age," Hogan said. More resources spent on educating Americans about healthy eating could go a long way toward saving lives, she added.
Steinbaum agreed that more must be done. "As time goes on and obesity increases, life expectancy is going to decrease," she said. "The drain on the health care system will rise."
The study was published online Jan. 16 in the American Journal of Public Health.
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The U.S. National Institute of Diabetes and Digestive and Kidney Diseases outlines the health risks of being overweight.