Mom's Weight Problem Is Child's Problem, Too
But Is Overweight Tendency Genetic or Environmental?
Jan. 25, 2005 -- Overweight 4-year-olds? It's a common problem these days. Childhood obesity is showing up at early ages -- and genetics seem to play a key role, researchers say.
By age 6, children are 15 times more likely to be obese if their mothers are overweight, new research shows.
The study indicates efforts to prevent childhood obesity should focus on these kids -- preferably by 4 years of age.
"Some kids clearly become overweight by 4 years old ... and they tend to be the children of overweight mothers," says researcher Robert I. Berkowitz, MD, executive director of the Behavioral Health Center at the Children's Hospital of Philadelphia. His study appears in the latest issue of the American Journal of Clinical Nutrition.
"It's an early signal to be concerned ... to help these children," Berkowitz tells WebMD. "There's no reason to wait for body fat to appear on these kids before intervening," he writes.
It's a call to action for pediatricians, says Robert Kramer, MD, a pediatric gastroenterologist and nutritionist at the Miller School of Medicine at University of Miami. He conducted his own study of preschool children in the Miami area -- finding that 34% were overweight or obese.
"Pediatricians measure a child's BMI, or they should be, at all well-child visits," Kramer tells WebMD. "They should be identifying those children as having high risk for developing obesity as an adult. Studies like this show that even before children show signs of obesity, if they have maternal risk, they should get intervention." BMI (body mass index) is an indicator of body fat.
Childhood Obesity in Toddlers Begins With Moms
With the epidemic of childhood obesity, both genetic vulnerability and environment are under the microscope. Researchers want to know: Who becomes obese? At what age does obesity begin?
Few long-term studies have examined these factors. However, two reports have identified the parents or overweight mothers specifically as key factors. Those findings prompted Berkowitz and his colleagues to investigate this link between childhood obesity and mothers' weight problems.
His study involved 70 children whose growth was followed from birth to age 6; 33 children had overweight mothers (the high-risk kids), and 27 kids had lean mothers (the low-risk kids).
At regular doctor visits, the kids' lean and fat body mass were measured.
- At age 2, the kids' weight and BMI were similar.
- By age 4, the high-risk kids were showing greater differences -- with higher weight, BMI, and waist measurements.
- By age 6, high-risk kids began to show evidence of more fat.
"For the first time [at age 6] fat mass in the high-risk children was significantly greater than that in the low-risk children, as was percentage of body fat," Berkowitz writes.
At age 6, 30% of the high-risk and 3% of the low-risk kids had high BMI. Six of the high-risk children were in highest BMI levels for their age. None of the low-risk kids were.
Some kids of overweight moms remained lean, he notes. "Their genes may be a little different, or their home environment may be different," says Berkowitz.
"We know that once a kid is overweight -- and if the family has weight problems -- that's a significant risk factor for later weight problems," he tells WebMD.