Nearly 90% of all diabetes cases worldwide are type 2—this research points to why.
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About 6% of all humans on earth and 9% of Americans have diabetes. Nine in 10 of these are type 2 diabetes (which you may have heard referred to as "adult onset" in previous years) while 1 in 10 have type 1 diabetes. Both relate to insulin's ability to impact blood sugar levels, but are different in that:

  • For type 1, the body doesn't produce insulin
  • For type 2, the body doesn't respond to insulin that's being produced

The current scientific opinion is that type 1 is almost definitely caused by genetics, while type 2 may be a combination of genetics and lifestyle factors. That's because having overweight or obesity, being less active and/or having high blood pressure or cholesterol have been correlated to type 2, according to the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK).

Losing weight could prevent or perhaps even reverse type 2 diabetes, reports the latest research, which was presented at the European Society of Cardiology Congress on August 31. And fascinatingly, body mass index (BMI) might be even more important than the genes you're born with in determining whether you acquire type 2 diabetes.

The researchers studied about 446,000 UK residents and assessed their genes for inherited risk as well as their height and weight to measure BMI, which is a calculation that assigns a number to your body size based on those two factors.

"The findings indicate that BMI is a much more powerful risk factor for diabetes than polygenic predisposition," noted principal investigator Professor Brian Ference of the University of Cambridge, UK, and University of Milan, Italy, in the report, using a term that refers to the combined effects of several genes on an individual's health.

Those in the highest BMI group (who averaged around a BMI of 35) had an 11-fold increased risk of getting a type 2 diabetes diagnosis than those in the lowest BMI group (who averaged around a BMI of 22). This was found to be true even when the researchers stripped away genetic risk. Beyond having overweight or obesity now, the investigators wanted to find out if how long you've had a higher BMI mattered, and they discovered that the duration of time of having a higher BMI didn't have an impact on the risk of diabetes.

"This suggests that when people cross a certain BMI threshold, their chances of diabetes go up and stay at that same high-risk level regardless of how long they are overweight," Ference told the European Society of Cardiology Congress. "It may also be possible to reverse diabetes by losing weight in the early stages before permanent damage occurs." (P.S. Here's a meal plan from our registered dietitians that might help those with prediabetes.)

All this being said, the jury is still out as to how helpful BMI truly is at predicting risk for chronic diseases, and it shouldn't be the only factor we consider to potentially diagnose a problem. (A doctor is the only one who can do that with a blood test, in this case.) Still, it's interesting to note the link and continue to watch emerging research as we attempt to limit people developing diabetes—and related health challenges—as much as possible. And in the meantime, it certainly can't hurt for us all to eat a bit more plant-based to reduce our chances of developing type 2 diabetes.