How long and how much a person is overweight is key to understanding their type 2 diabetes risk.
Obesity is a well established risk factor for type 2 diabetes, but some people who are overweight never develop the condition. A new study explains that the relationship between obesity and diabetes may be more complicated.
After tracking the health of 8,000 teens and young adults for a number of years, researchers from the University of Michigan found that the length of time a person has been obese and the degree to which they are overweight together determine whether or not a person will develop type 2 diabetes.
A body mass index measurement over 25 is considered overweight. The team suggested multiplying the number of years a person has been overweight by the number of BMI units they are over 25 to determine their true diabetes risk. This number represents a person’s “lifetime dose” of diabetes.
For example, a person who has had a BMI of 35 (which is 10 points overweight) for 10 years would have 100 years’ worth of overweight BMI. This number could be far more accurate when diagnosing a person’s type 2 diabetes risk than simply measuring their body mass one time.
The researchers said that understanding exactly how obesity puts a person at risk for type 2 diabetes is important, as a growing number of young people are now overweight. The findings of the study could have important implications for future generations.
"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 lead author Joyce Lee, MD. "When you add the findings from this study, rates of diabetes in the United States may rise even higher than previously predicted."