For children, obesity often begins in preschool, suggesting that pediatricians need to act early to prevent and treat excess weight in childhood, new research shows.

Furthermore, referring kids who have already gained too much weight to a pediatric endocrinologist does little to help them shed excess pounds.

These findings suggest that obese children need more than a visit to the doctor in order to lose weight, study author Dr. Teresa Quattrin stated.

She explained that most parents of obese children are also obese themselves, and children are very influenced by the adults around them. So, asking a child to change her eating habits without asking her parents to change is very hard on her, Quattrin noted.

"We have to be aware that this problem starts early," said the researcher, based at the Women's and Children's Hospital of Buffalo, in New York. "We have to address it early, and use, if we can, a family approach," she said.

Teaching kids good eating and exercise habits early is essential, she added, since once kids start a routine, it's very hard to break out of it. "Once you are used to eating ice cream three times per week...making a change is very difficult," she said.

In the journal Pediatrics, Quattrin and her colleagues write that obese children are likely to become obese adults, which puts them at risk of numerous diseases related to obesity that are already being seen in children, such as type 2 diabetes.

To determine what can help obese children lose weight, the researchers reviewed the charts of 587 obese children who visited a pediatric endocrinologist, who treats childhood hormone problems.

The medical records showed that 4 out of 5 children became obese before their sixth birthdays, and came to the endocrinologist an average of 4 years after gaining weight.

More than half of children who took blood tests showed high levels of cholesterol and insulin, a sign they were at risk of diabetes. Half of mothers and more than half of fathers were also obese.

Although more than one-third of children lost weight after visiting the endocrinologist, only five lost enough weight that they no longer met the criteria for being obese.

In an interview, Quattrin explained that obese children visit the endocrinologist because there is a "very small probability" that they could have a thyroid problem. In addition, the endocrinologist can counsel the child about obesity, and how to prevent diabetes.

However, the results show that a "one-time thing doesn't make an impact," she said.

She added that asking a "team" to follow obese kids and their families will be "costly," but might save money in the long run by reducing the future costs of treating obesity-related illnesses.