Doctor measuring obese man stomach.

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DALLAS, Texas — The link between obesity and diabetes has not been in question for nearly two decades. While most health experts are in agreement weight gain is the main driver of the condition, a new study in revealing the unnerving scope of the problem. Researchers from Northwestern University say between one-third and half of all new type 2 diabetes cases in the United States each year are caused by obesity.

The report, released by the American Heart Association, finds 30 to 53 percent of new diabetes cases have a link to the patient’s weight. Type 2 diabetes is the most common form of the condition; affecting over 31 million Americans around the country.

Along with being obese, being over age 45, having a family history of diabetes, and being less physically active are all risk factors for developing the blood sugar disorder. Researchers say type 2 diabetes is also more common among Americans who are Black, Hispanic, Asian, Pacific Islanders, Native Alaskans, or American Indians.

Although the condition can be a serious health risk to older adults, the report finds the number of deaths among type 2 diabetes patients younger than 65 is increasing. So are the number of serious health complications like amputations and hospitalizations. Being obese or having diabetes can also increase the risk of heart attack or stroke.

How can someone prevent diabetes?

The simplest answer is lose weight. Study authors say eating healthy, being physically active, getting out of the “obese” category can either delay or completely prevent developing type 2 diabetes. According to the National Diabetes Prevention Program, an at-risk person losing five to seven percent of their body weight can reduce their chances of developing type 2 diabetes by 58 percent. That number grows to 70 percent if the person is over 60 years-old.

“Our study highlights the meaningful impact that reducing obesity could have on Type 2 diabetes prevention in the United States. Decreasing obesity needs to be a priority. Public health efforts that support healthy lifestyles, such as increasing access to nutritious foods, promoting physical activity and developing community programs to prevent obesity, could substantially reduce new cases of Type 2 diabetes,” says the study’s first author Natalie A. Cameron, M.D. in a media release.

Who is most at risk of developing diabetes?

Researchers examined health data from two major sources, the Multi-Ethnic Study of Atherosclerosis (MESA) and four cycles of the National Health and Nutrition Examination Survey (NHANES) conducted between 2001 and 2016. The team focused specifically on whites, Blacks, and Mexican-Americans between 45 and 79 years-old. These participants did not have heart disease, type 1 or type 2 diabetes at the start of the studies. Researchers compared the prevalence of obesity among these groups and the increased risk for diabetes those extra pounds added over the years.

For participants in the NHANES reports, overall obesity rates increased from 34 to 41 percent during the study. Type 2 diabetes rates were consistently higher among obese patients.

For Americans in the MESA report, one in 10 (11.6%) developed type 2 diabetes over a nine-year period. Study authors discovered that obese patients are almost three times more likely to develop the condition in comparison to people with a normal weight (20% vs. 7.3%).

Individuals with a lower income also seem to be more at risk for diabetes. Researchers say participants with family incomes lower than $50,000 suffered higher rates of type 2 diabetes. Blacks and Mexican-Americans in the reports also appear more likely to develop the condition.

Although obesity rates among white females were the lowest of any group in the study, researchers discovered these women also have the greatest risk of developing type 2 diabetes if they are obese.

Not a complete picture of obesity and diabetes

Given the very specific nature of the study, researchers admit their results could vary among other populations in the United States. They also note the ongoing coronavirus pandemic is further exacerbating the diabetes and obesity epidemics the country is dealing with.

“Our study confirms there is a higher prevalence of obesity among non-Hispanic Black adults and Mexican-American adults compared to non-Hispanic white adults. We suspect these differences may point to important social determinants of health that contribute to new cases of Type 2 diabetes in addition to obesity,” says Cameron, a resident physician of internal medicine at the McGaw Medical Center of Northwestern University.

“Additionally, the obesity epidemic has collided with the COVID-19 pandemic,” adds Sadiya S. Khan, M.D., M.Sc., the study’s senior author. “The greater severity of COVID-19 infection in individuals with obesity is concerning because of the growing burden of adverse health consequences they could experience in the coming years; therefore, further efforts are needed to help more adults adopt healthier lifestyles and hopefully reduce the prevalence of obesity.”

The study appears in the Journal of the American Heart Association.

About Chris Melore

Chris Melore has been a writer, researcher, editor, and producer in the New York-area since 2006. He won a local Emmy award for his work in sports television in 2011.

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