Metabolic syndrome in adults occurs when they have at least three risk factors from among abdominal obesity (waist circumference more than 35 inches for women; 40 inches for men); low HDL (""good"") cholesterol; high triglycerides; high fasting glucose; and high blood pressure.

Although sometimes difficult to diagnosis in children, similar clustering can appear in childhood. The report, published online Jan. 12 in Circulation, called for clinicians to measure and to treat the individual pieces of the syndrome in children while intervening to break bad diet and exercise habits.

""The adverse risk factors and the connections between them that eventually lead to the metabolic syndrome begin in childhood,"" Dr. Julia Steinberger, director of Pediatric Echocardiography and Preventive Cardiology at the University of Minnesota Children's Hospital in Minneapolis, said in an American Heart Association news release. She chaired the group that wrote the report.

Much of the increased risk is tied to the continued increase in childhood obesity, which the heart association said is around 17 percent of all children aged 6 to 19. Having a body-mass index at or above the 95th percentile for the child's age is considered being obese.

""We can say that childhood obesity is our biggest problem,"" Steinberger said. ""It's been shown that when diet and exercise are improved in overweight children, the structure and function of blood vessels improves even in the absence of weight loss.""