BETHESDA, MD — Children who are overweight as toddlers or preschoolers are more likely to be overweight or obese in early adolescence, report researchers in a collaborative study by the National Institutes of Health (NIH) and several academic institutions.

Researchers collected height and weight measurements of a sample of children, beginning at age 2 and continuing until age 12. Their analysis, which appeared in the September Pediatrics, provides some of the strongest evidence to date that being overweight in early childhood increases the chance for being overweight in later life.

“These findings underscore the need to maintain a healthy weight beginning in early childhood,” says Duane Alexander, the director of NIH's National Institute of Child Health and Human Development, which funded the study. “Contrary to popular belief, young children who are overweight or obese typically won't lose the extra weight simply as a result of getting older.”

The strength of the current analysis is that it was conducted on data collected during frequent intervals over an extended period of time, from age 2 through age 12. Also, the children who took part in the study were born in 1991, and so were growing up during the current trend of overweight and obesity in the general population, researchers noted.

Children who were overweight at least once from ages 2 to 4 ½ were five times more likely to be overweight at age 12 when compared to children who were not overweight from ages 2 to 4 ½. The more times a child was overweight from ages 7 through 11, the greater the chances the child would be overweight at age 12 in comparison to children who were not overweight from ages 7 through 11.

The study's authors also found that no children in the study who were below the 50th percentile at preschool or elementary school age were overweight at age 12.