MONDAY, Sept. 12 (HealthDay News) -- It's long been known that obesity increases diabetes risk, but a new study finds that the amount of excess weight someone carries -- and how long it's carried -- can make that risk even higher.
That's especially worrisome given the growing number of obese children and teens who will spend more years of their lives obese than prior generations, researchers from the University of Michigan Health System warn in a university news release.
"Our study finds that the relationship between weight and type 2 diabetes is similar to the relationship between smoking and the risk of lung cancer," said the study's lead author Dr. Joyce Lee, a pediatric endocrinologist at the University of Michigan C.S. Mott Children's Hospital. "The amount of excess weight that you carry, and the number of years for which you carry it, dramatically increase your risk of diabetes."
This has the potential to continue to push up rates of diabetes in the United States, Lee added.
"We know that, due to the childhood obesity epidemic, younger generations of Americans are becoming heavier much earlier in life, and are carrying the extra weight for longer periods over their lifetimes," said Lee. "When you add the findings from this study, rates of diabetes in the United States may rise even higher than previously predicted."
Researchers examined information on roughly 8,000 teens and young adults and calculated how far above a certain body mass index (or BMI, a calculation based on weight and height) they were and for how long. The study found those with a BMI of 25 or higher (overweight) or 35 and higher (30 and up is obese) for a greater length of time had a higher risk of diabetes.
For example, individuals with a body mass index of 35 for 10 years were considered to have the equivalent of 100 years of excess BMI -- a considerable cumulative "dose" of excess weight.
What's more, black and Hispanic participants had a higher risk for diabetes than whites with the same amount of excess weight over time, the researchers noted. Among those with a BMI of 35 or more, Hispanics were twice as likely to develop diabetes than whites. Blacks in this group also had a 1.5 times greater risk of developing diabetes than whites.
The study's authors said the findings suggest obesity prevention programs should focus on teens and young adults, particularly minorities.
The study was published online ahead of the September print issue of the Archives of Pediatric Adolescent Medicine.
The U.S. Centers for Disease Control and Prevention provides more information on the health consequences of obesity.
-- Mary Elizabeth Dallas
SOURCE: University of Michigan Health System, news release, September 6, 2011
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