Childhood Obesity Carries Serious Health Risks

Childhood obesity in the United States has steadily increased over the past two decades, especially among Hispanic children. Results from the first family-based study of the genetics of childhood obesity and risk factors for metabolic syndrome were reported by Dr. Nancy Butte and colleagues in the December 2005 issue of Pediatric Research. Dr. Butte is a Professor of Pediatrics at the Children’s Nutrition Research Center.

The study included 1,030 children and 600 parents from 319 Hispanic families. Twenty to 28 percent of the children—some as young as 4 years—exhibited the characteristics of metabolic syndrome, which is typically seen in middle-aged, obese adults. Dr. Butte explains, “The metabolic syndrome is defined as having three or more metabolic risk factors including abdominal obesity, high blood glucose, high blood pressure, abnormal cholesterol and triglycerides that make one more susceptible to diabetes and cardiovascular disease.” One of the specific goals of the study was to estimate the genetic contribution (heritability) for each component of metabolic syndrome. Quantitative genetic analysis showed that waist circumference, cholesterol, triglycerides, glucose and systolic blood pressure are all highly heritable.

In this study, the prevalence of metabolic syndrome increased with the severity of obesity. These results suggest that all obese children, regardless of ethnicity, should be routinely screened for abnormal fasting blood glucose and lipid levels as well as blood pressure. Researchers expect to find similar genes influencing obesity and related metabolic complications in children and adults, but obese children who develop the metabolic syndrome likely carry a heavier genetic burden.

Dr. Butte is optimistic that an under-standing of the genetic contributions to components of metabolic syndrome in overweight Hispanic children may lead to new methods for prevention and treatment. Nevertheless, she reminds us, “It is also important to consider environ-mental influences on the prevalence of childhood obesity and related metabolic complications.” Parents should take steps to reduce the risk of the metabolic syndrome in their children at an early age. The best way to do this is to assure that the children eat a balanced, healthy diet and obtain ample amounts of physical activity. Parents also need to remember that their children mimic them. That means that parents should model healthy eating behaviors and be physically active.