A new study reveals that nearly 1 out of every 5 American children is obese. These findings, published in the latest issue of Archives of Pediatrics & Adolescent Medicine, shed light on a growing childhood obesity problem in America, especially among certain minorities.

Researchers analyzed data for 8,550 preschoolers born in 2001, and discovered that nearly 13 percent of Asian children were obese, as well as 16 percent of whites, 22 percent of Hispanics, 21 percent of African Americans and 31 percent of American Indians.

Researchers drew the conclusion that “Racial/ethnic disparities in obesity are apparent in 4-year-old US children. The highest prevalence is in American Indian/Native Alaskan children, in whom obesity is twice as common as in non-Hispanic white or Asian children.”

"The magnitude of these differences was larger than we expected, and it is surprising to see differences by racial groups present so early in childhood," Sarah Anderson, one of the researchers, told the Associated Press.

The study did not examine possible causes for these rates of obesity.

You can view the study here.