Children are becoming obese as early as 3 years old, and obese children as young as 10 are showing abnormal liver function and abnormally high insulin levels, conditions that might lead to type 2 diabetes, researchers from the University at Buffalo say.
More unsettling, the researchers say, family counseling on diet and exercise had little effect on those in the study.
Obese children who were followed for an average of two years after seeing a specialist gained even more weight, their findings showed.
"Childhood obesity not only affects a child's self-esteem, it also is associated with multiple medical consequences," said Dr. Teresa Quattrin, an associate professor of pediatrics and director of the study.
The results of the study recently were presented at the Pediatric Academic Societies meeting in Seattle.
A high insulin level is believed to be related to type 2 diabetes, especially in families with a history of diabetes. The incidence of type 2 diabetes in children has risen significantly in recent years, along with a rise in obesity.
"Children at risk of obesity must be identified very early, even at the preschool level," Quattrin said. "Obese children often have obese parents, so an effective family-based, multifactor intervention program should begin as soon as obesity is diagnosed."
The study, conducted by Quattrin and Dr. Emily Liu, research assistant professor of pediatrics at Kaleida Health's Women's and Children's Hospital, sought to identify characteristics of the obese children referred to the hospital's endocrine specialists, determine the age of the onset of obesity and analyze the results of treatment.
In the United States, 16 percent to 33 percent of children and adolescents are obese, and the level of childhood obesity is rising.
Compared with children of normal weight, overweight children are much more likely to become overweight adults, with all of the health problems associated with adult obesity. Because doctors have few treatment options, obese children often are referred to an endocrinologist.
The UB researchers reviewed medical records of 385 children between 1984 and 2002. At the initial visit, parents or guardians received extensive counseling on diet and activity recommendations, along with written guidelines, and were advised to meet with a dietitian.
Despite a possible genetic predisposition for obesity, other factors play important roles, including the availability of food at home and school, watching television, lack of exercise and the role models of parents, according to experts.
Results showed that 86 percent of 177 children were obese before the age of 6, and children were obese for an average of three years before they were referred to an endocrinologist.
Abnormally high insulin levels were found in children as young as 4 years old, and eight of 43 children with abnormally high insulin levels were younger than 10. In addition, 13 percent of 147 children had abnormal liver-function tests.
The research was supported, in part, by a summer student grant from the Lawson Wilkins Pediatric Endocrine Society to medical student Natalie Shaw and a Stransky Award from the Women's and Children's Foundation.