WESTWOOD (CBSLA.com) – Nearly half of California adults have prediabetes or undiagnosed diabetes, UCLA researchers said Thursday.

According to a study by UCLA Center for Health Policy Research, 13 million adults, or 46 percent of the state’s population, are believed to be living with the precursor of type 2 diabetes or undiagnosed diabetes. Another 2.5 million adults, or 9 percent of the state’s population, have already been diagnosed with diabetes.

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Researchers predict that 33 percent of young adults, aged 18 to 39, are prediabetic, which is rare since diabetes is generally more common among older adults.

Dr. Susan Babey is one of the authors of the study. “I think with more than half the people being at risk or having diabetes, I think an epidemic would not be out of line.”

“I think it’s probably a number of factors involved, and it’s related to what we’ve been seeing in terms of increasing obesity rates, a lack of physical activity or poor diets,” Babey said.

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According to researchers, up to 30 percent of residents living with prediabetes will develop type 2 diabetes within five years. As many as 70 percent of adults will develop the disease within their lifetime.

“This is the clearest indication to date that the diabetes epidemic is out of control and getting worse,” said Dr. Harold Goldstein of the California Center for Public Health Advocacy, which commissioned the study. “With limited availability of healthy food in low-income communities, a preponderance of soda and junk-food marketing and urban neighborhoods lacking safe places to play, we have created a world where diabetes is the natural consequence.”

Health officials said many people do not get tested for prediabetes because the test is often not covered by insurance.

Prediabetes can be reversed with proper diet and exercise.

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