Ravindranath Duggirala, a scientist at Texas Biomedical Research Institute in San Antonio, and colleagues examined 670 children ages 6-17, from predominantly lower-income extended Mexican-American families, many of whose adult members have increased risk of diabetes.
They found a striking proportion had metabolic syndrome -- warning signs of diabetes, such as belly fat, high levels of blood sugar, elevated blood pressure and high insulin levels.
"Experiencing metabolic syndrome and related risk factors this early in life significantly increases risk of developing hypertension, diabetes, cardiovascular disease and other chronic health problems years earlier than might otherwise have been expected," Duggirala said in a statement.
An estimated 2.5 million U.S. adolescents have metabolic syndrome, with minority groups such as Mexican-Americans being particularly vulnerable.
The study, published in the journal Human Genetics, found nearly 53 percent of the Mexican-American children were overweight or obese, and 13 percent had pre-diabetes. Overall, 19 percent, or almost 1-in-5, of the young people exhibited metabolic syndrome, the study found.