WASHINGTON (Reuters) - New government estimates show that nearly 24 million people in the United States have diabetes, an increase of more than 3 million in two years.

A diabetic patient injects himself with insulin at the J.W.C.H. safety-net clinic in the center of Skid Row in downtown Los Angeles July 30, 2007. New government estimates show that nearly 24 million people in the United States have diabetes, an increase of more than 3 million in two years. REUTERS/Lucy Nicholson

This means that nearly 8 percent of the U.S. population has diabetes, mostly the type-2 diabetes linked with obesity, poor diet and a lack of exercise, the U.S. Centers for Disease Control and Prevention said on Tuesday.

The estimates, based on 2007 data, also show that 57 million people have pre-diabetes, a condition that puts people at increased risk for diabetes. And up to 25 percent of people with diabetes do not know they have it, the CDC said -- down from 30 percent two years ago.

Almost 25 percent of the population 60 years and older had diabetes in 2007, the CDC found.

The highest rates are among Native Americans and Alaska Natives, with 16.5 percent affected.

Close to 12 percent of blacks and 10 percent of Hispanics have diabetes, but just 7.5 percent of Asian Americans and 6.6 percent of whites.

Diabetes causes the body to produce less insulin, or to use it less effectively, which in turn causes blood sugar levels to rise. This in turn damages blood vessels and organs, leading to blindness, kidney disease, limb loss and heart disease.

It is the seventh-leading cause of death in the United States.

“It is concerning to know that we have more people developing diabetes, and these data are a reminder of the importance of increasing awareness of this condition, especially among people who are at high risk,” said Dr. Ann Albright, director of the CDC’s Division of Diabetes Translation.

“On the other hand, it is good to see that more people are aware that they have diabetes. That is an indication that our efforts to increase awareness are working, and more importantly, that more people are better prepared to manage this disease and its complications.” (Reporting by Maggie Fox; Editing by Julie Steenhuysen)