Blood glucose health is deteriorating in obese adults — raising the risk of Type 2 diabetes and cardiovascular complications, according to new research in the Journal of the American Heart Association.

“The adverse impact of obesity on blood sugar status appears to develop over a longer period, and the population is still experiencing progressive worsening of glycemic status,” said Fangjian Guo, M.D., Ph.D., study co-author and assistant professor of obstetrics and gynecology at the University of Texas in Galveston.

“If blood sugar goes high too often, it can overwork the body’s ability to keep blood sugar in healthy ranges, increasing the risk of developing diabetes complications.”

Diabetes is a risk factor for heart disease and stroke.

Analyzing data on more than 18,000 obese adults in the National Health and Nutrition Examination Survey in 1988-2014, researchers found:

  • The rate of diabetes increased as much as 19 percent, worsening blood sugar levels.
  • The rate of obese adults free of three cardiovascular disease risk factors — diabetes and high cholesterol and blood pressure — remained stable at about 15 percent.
  • The rate of obese adults with all three risk factors increased by 37 percent, with about 22 percent still fighting all three risk factors.
  • The risk factors remained lowest among those ages 20-39, but decreased among people 40 and older.
  • Average systolic blood pressure and total cholesterol levels dropped overall during 1988-92 and 2011-14, except for blood pressure in young adults.

The findings suggest controlling weight in obese adults to reduce the risk of developing of Type 2 diabetes should be a public health priority, researchers said.

“Diabetes places patients at very high risk for heart attack and coronary death,” said W. Timothy Garvey, M.D., study co-author and professor of medicine and chair of the Department of Nutrition Sciences at the University of Alabama in Birmingham.

“Obese adults at high risk for diabetes and heart disease may require more intense approaches to control blood sugar and achieve weight loss, such as healthy meal plans and physical activity.”

Obesity impairs the body’s ability to properly process blood sugar. Losing weight can reverse the effect.

Recent obesity rates have leveled off after three decades of steadily climbing. More than one-third or about 35 percent of American adults are obese.