Obesity in infants can be diagnosed at 6 months, study shows

By analyzing the electronic medical records of babies seen for routine "well-child" visits to the UTMB pediatric clinic, the investigators found that about 16 percent of 6-month-olds fit the study's criterion for obesity -- a weight-for-length ratio that put them in the top 5 percent of all babies in their age group. (Weight for length was used instead of the conventional body mass index because BMI is based on weight and height as measured while standing, which neither 6-month-olds nor 24-month-olds can do well enough to measure.) Further analysis of the records indicated that obese 2-year-olds were much more likely to have been obese at 6 months than 2-year-olds who were not obese.

The obese babies' medical records rarely showed that clinicians had addressed the issue at either 6-month or 24-month visits, despite a well-established connection between obesity at a young age and obesity later in life, which is linked to such serious health problems as diabetes, heart disease and high blood pressure.

"Until very recently, pediatricians really haven't been focusing on obesity in babies," said Dr. David McCormick, UTMB clinical professor of pediatrics and senior author of the study, "Infant Obesity: Are We Ready to Make this Diagnosis?" which is now online in the Journal of Pediatrics. "We're just getting a handle on it descriptively right now. What we're hoping to do is alert our colleagues and our parents. If we address weight management through nutrition and exercise as early in life as possible, it's going to work a lot better."

According to McCormick, pediatricians confronting infant obesity can recommend a number of measures that other research has shown are linked to healthy weight, measures that should be particularly effective because babies' mothers have much more control over their diets than mothers of older children do.

"Studies have shown that exclusive breastfeeding -- breastfeeding alone, not breastfeeding combined with bottle-feeding -- prevents obesity," McCormick said. "Getting enough fiber -- eating apples instead of drinking apple juice, for example -- also helps keep babies on track to a healthy weight. By contrast, improper early introduction of cereal by adding it to an infant's bottle promotes obesity."

McCormick observed that maternal data collected in his group's investigation matched well with other studies of children and adolescents that showed higher odds of obesity among boys and girls whose mothers were already obese before becoming pregnant or who gained an excessive amount of weight during pregnancy. Such results, he said, added even more urgency to the need to deal with childhood weight issues effectively and address what could be a multigenerational cycle of obesity.

"We need to do a lot better as clinicians and educators at getting our community educated and working through the entire age spectrum, because babies who are overweight are more likely to be overweight children and adolescents, and then later, when obese women are ready to have a family, their babies are more likely to become obese," McCormick said. "We need to deal with this through all ages and through pregnancy, because if a woman is already overweight when she becomes pregnant, it's extremely difficult for her to do anything about her weight at that point."

Other authors of this study included UTMB assistant professors Dr. Kwabena Sarpong and Dr. Sunil Jain, medical student Lindsay Jordan, and assistant director of research support services Laura Ray. The National Institutes of Health and the U.S. Public Health Service helped support this research through grants to the UTMB General Clinical Research Center.