Up to half of new cases of type 2 diabetes in the US are linked to obesity, study finds

New research released Wednesday highlights the role of obesity in type 2 diabetes. It suggests that obesity plays a major role in nearly half of the new cases of diabetes that occur each year in the United States.

The link between obesity and type 2 diabetes – a condition where blood sugar gets out of hand and stays too high – is well established. But the authors say their new study, published in the Journal of the American Heart Association, provides a more recent estimate of how often obesity contributes to diabetes, an estimate that relies on longer-term data than previous studies. The study was conducted by researchers at the Feinberg School of Medicine at Northwestern University in Chicago.

They looked at years of data from two sources. One of them was the National Health and Nutrition Examination Survey (NHANES), an annual survey that asks a nationally representative group of Americans about their lifestyle and eating habits. The other was the Multi-Ethnic Atherosclerosis Study (MESA), an ongoing study of over 6,000 volunteers whose health status has been monitored since 1999 to study heart disease. The combined data gave researchers two different ways to study the health of Americans over a long period of time, especially middle-aged to elderly people.

Between 2001 and 2004, according to NHANES data, about 34% of Americans aged 45 to 79 met criteria for obesity (a body mass index, or BMI, of age 30 and over); between 2013 and 2016, this percentage rose to 41%. In MESA data, 11.6% of participants without pre-existing diabetes developed the disease over a median of nine years. And those who were obese in the MESA study were about three times more likely than non-obese people to develop diabetes during that time (20% vs. 7.3%).

Based on MESA and NHANES data, researchers estimate that obesity is now associated with 30% to 53% of new diabetes cases seen each year. However, the impact of this relationship is not equal across all groups of people. Obesity and type 2 diabetes are more common in people of color than in whites, and black and Hispanic Americans are also more likely to die from diabetes. But the link between obesity and diabetes was actually strongest among white women, despite this group having the lowest obesity rates overall.

“Our study highlights the significant impact that reducing obesity could have on preventing type 2 diabetes in the United States. Reducing obesity must be a priority, ”said Natalie Cameron, lead author of the study, internal medicine intern at Northwestern University in Chicago, in a statement. released by the American Heart Association, which helped fund this study with the federal government. “Public health efforts that support healthy lifestyles, such as improving access to nutritious foods, promoting physical activity and developing community programs to prevent obesity, could significantly reduce new cases of type 2 diabetes. “

Other research has found that the incidence of new diabetes cases in the United States declined between 2008 and 2018, even as the obesity rate increased over the same period. But the rate of annual new cases has not declined among people under the age of 20, and diabetes remains the seventh leading cause of death in the United States, contributing to 87,647 deaths in 2017. The authors also fear that covid-19 pandemic could further worsen the situation, both directly and indirectly (some research even suggested that covid-19 infection may directly contribute to new-onset diabetes).

“The greater severity of covid-19 infection in obese people is of concern due to the increasing burden of adverse health consequences they may experience in the years to come; therefore, more efforts are needed to help more adults adopt healthier lifestyles and hopefully reduce the prevalence of obesity, ”said lead study author Sadiya Khan in a statement.