Traci Glazner's 5-month-old daughter, Faye, has been long and lean since birth.
"When Faye was born she was 19 and a half inches and weighed 6 pounds, 3 ounces," Glazner said.
Birth weight is one factor that could predict whether a baby becomes obese later in life. Researchers in England say there is a simple formula that can determine which newborns are most at risk. It also includes the body mass index of the parents, the number of people in the household, the mother's professional status and whether she smoked during pregnancy.
"That calculation would have an 80 percent of being right," said Dr. Jonathan Fanaroff of Rainbow Babies & Children's Hospital. "It really does a good job. It is an important tool."
Childhood obesity rates are a big concern in the United States. More than one-third of children and teens are overweight or obese.
Doctors say once a child gains weight, it's difficult for them to lose it, so prevention from the earliest age is key.
"Maybe this calculator will get some families who might otherwise not take a healthy lifestyle seriously to take it more seriously," Fanaroff said.
Glazner already does something very important that can help prevent child obesity-- she breast-feeds her baby exclusively.
"I nurse Faye 100 percent. She hasn't started any solid foods yet, so all she's had is breast milk," Glazner said.
And like she does with her other children, Glazner plans to give baby Faye well-balanced meals and keep her active as she gets older.
Researchers did their original study on 4,000 children from Finland. They say the formula also proved accurate in studies in the United States and Italy.
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