Diabetes is one of America’s greatest public health battles.

And Louisiana is on the front lines, with 49 of 64 parishes included in the “diabetes belt,” a string of counties and parishes in the Southeast with high occurrences of the disease.

The state ranks fourth in the nation in the rate of diabetes diagnoses, according to the U.S. Centers for Disease Control and Prevention, with 10 percent of adults living with the disease. The national average is 8 percent, a rate that has steadily climbed over the past 20 years.

“It parallels the rise in obesity,” said Dr. William Cefalu, executive director of the Pennington Biomedical Research Center. “It’s a combination. We’ve become more sedentary, too.”

Diabetes sufferers have too much glucose, a form of sugar, in their blood. Too much of that sugar can cause irreparable harm, said Dr. Phillip Ehlers, a Livingston-based doctor.

“It affects just about every part of the body,” Ehlers told an audience at a Peoples Health forum. “You’ve got blood sugar floating around in your body, and blood has to go everywhere. It causes kidney disease, nerve damage.”

A hormone called insulin normally regulates the amount of glucose in the blood, but those with diabetes either don’t make insulin, or their bodies do not use it properly.

Three types of diabetes exist. Type 1 is usually diagnosed in children whose bodies do not make insulin. Another form, gestational diabetes, affects some pregnant women.

Most people diagnosed with the disease — 95 percent — suffer from Type 2 diabetes, often called “adult onset” diabetes, according to the CDC. It occurs when the pancreas cannot produce enough insulin. Many Americans, including celebrities like Baton Rouge native Randy Jackson, cooking queen Paula Deen, Republican pundit Mike Huckabee, game show host Drew Carey and singer Patti LaBelle, developed Type 2 diabetes as they aged, became less active and gained weight.

But researchers are seeing more children diagnosed with it along with other obesity-related diseases, such as high blood pressure and high cholesterol.

Doctors diagnose diabetes with a routine blood sugar test, which measures the milligrams of glucose per deciliter (1/10th of a liter) of blood. Patients usually fast before the test so food and drinks will not affect the results. A blood sugar level of 126 or higher indicates diabetes, but doctors usually measure on two separate occasions before confirming a diagnosis, Ehlers said.

Blood sugar levels between 100 and 125 mean a patient is prediabetec and in danger of becoming diabetic soon. About 33 percent of Americans are prediabetic, according to the CDC study, and many are unaware of it, Cefalu said.

While sugar and carbohydrates — foods like potatoes and bread that turn to sugar — would seem the cause of prediabetes, the condition is more complex, said Dr. Catherine Champagne, a professor and nutritionist at Pennington.

Being overweight is the top risk factor for becoming diabetic, Champagne said, with genetics the second. “Overweight people may never develop Type 2 diabetes,” she said, “but people who have Type 2 diabetes are typically overweight or very overweight or obese.”

Lifestyle changes — a healthy diet and increased exercise — can stall the disease’s onset, but “most people diagnosed as prediabetic will become diabetic within 10 years,” Ehlers said.

A series of studies at Pennington found most participants can lose weight over a period of six months, shrinking their chances of becoming diabetic. “They get tired of behaving and revert to their old ways and the weight comes back,” said Champagne. “I think as long as we’re dealing with people, it’s going to be a continual problem.”