An adult with a BMI over 30 is considered obese, so Canadian researchers looked at nearly 16 thousand obese people with an average BMI of 36-point-two.
Results show age and Type 2 diabetes were the strongest risk factors for death, while BMI was the weakest.
Researchers say the next step would be to determine a low - moderate - and high risk threshold to help people make an informed decision.
"I think the paper is telling us something that many clinicians and investigators knew, that having diabetes is a risk for your health - even higher than being overweight," says Dr. Bartolome Burguera, an endocrinologist with the Cleveland Clinic.
The findings appear online in "JAMA Surgery."
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