Date: August 11, 2006 11:01:58 AM PDT
Subject: "Diet & Exercise" Obesity Epidemic: Obese-at-Birth Rate DOUBLES
New research documents increasing obesity among infants
By Judith Graham
Chicago Tribune, August 9, 2006
http://www.belleville.com/mld/belleville/news/nation/15237107.htm
CHICAGO - Add babies to the growing ranks of overweight Americans.
Harvard Medical School researchers reported Wednesday that the percentage of infants who are significantly overweight rose 73.5 percent over two decades.
Though their study indicates just 5.9 percent of the country's infants fall into that category - or about 242,000 of the 4.1 million born each year - the trend could have worrisome implications for the nation's obesity epidemic.
Other research suggests that babies who gain excessive weight face a higher risk of being overweight in later childhood and adulthood.
Several trends are behind the increase. More infants are large for their gestational age at birth than a quarter-century ago, in part because more moms are overweight and develop gestational diabetes while pregnant. In addition, more babies are putting on pounds rapidly in the first few months of life.
"Even our very youngest children are gaining excess weight, not just adults and adolescents," said Matthew Gillman, senior author and associate professor of ambulatory care and prevention at Harvard.
"Our obesity prevention efforts need to start at the earliest stages of human development," he said.
That doesn't mean parents should put babies with telltale rolls of fat on diets, doctors said. Infants' health depends on good nutrition, and many babies will thin out over time. But it does imply moms and dads should know how much food they're giving infants and talk to their pediatricians about nutritional concerns.
The Harvard study, published in the July issue of the journal Obesity, looked at extremely chubby infants less than 6 months old. Their weight adjusted for height placed them at or above the 95th percentile on standard growth charts, a cut-off point the researchers set for being overweight.
A 6-month-old baby boy just under 27 inches long - an average length - would weigh about 17.5 pounds at the 50th percentile and more than 21 pounds at the 95th percentile, according to the growth charts.
The research examined data for more than 120,000 Massachusetts children up to age 6, but its most notable results have to do with infants. Previous research has documented a sharp rise in the percentage of overweight preschool children without separating out results for babies.
The data showed that in 1980, just 3.4 percent of infants less than 6 months old were overweight. By 2001, it was 5.9 percent, and researchers think the trend has continued since.
The findings did not surprise several Chicago-area pediatricians. "Across the board, we're seeing heavier infants, especially in our Hispanic and African-American families," said Sam Grief, a family physician at the University of Illinois at Chicago Medical Center.
"Absolutely, we are seeing more of these larger infants," agreed Michael Lotke, a pediatrician at Chicago's Sinai Health System and medical director of its pediatric weight management program.
Of course, some youngsters at the top of the growth charts after birth will shed extra baby weight as they begin to crawl and walk. Some will be of average weight in childhood, adolescence and adulthood.
But a relatively new body of research has shown a connection between early weight gain and extra pounds later in life.
"If you look at weight gain early in life - during the first year, the first four months, even the first week - and then look at weight status in childhood and adulthood, you find a strong association," said Nicolas Stettler, assistant professor of pediatrics and epidemiology at Children's Hospital of Philadelphia.
Animal studies underscore the finding, showing that over-fed rats are more likely to become obese and diabetic.
"It could be that if you're over-fed early in life, that may affect the brain's neurochemistry during a key development period and re-program a person to eat to excess," Stettler said. Another hypothesis is that insulin secretion and metabolism could be altered in this early period.
A behavioral change also might be involved: Humans and other animals may learn to override the feeling of being satiated and continue eating when food is offered even if they're not really hungry, Stettler said. Or, being overweight may have a strong genetic component that first expresses itself in infancy and remains a risk factor throughout life.
When Thea Yosowitz sees infants gain weight rapidly, she does an in-depth history to find out what they are being fed, how often and the growth experience of other kids in the family. Yosowitz is a pediatrician at Rush University Medical Center's pediatric primary care clinic.
Parents who bottle-feed infants sometimes mistakenly expect babies to finish what's in the bottle or start giving juice too early. "We don't want parents to put their baby on a diet, but we do want to make sure that when the infant pushes the bottle away the parent realizes they're done and it's time to stop feeding," Yosowitz said.
If the baby still cries, "give them a pacifier or a finger and see if that calms them down," she advised. "If they're happy with that, they probably just wanted to suck a while longer."
The problem with fat babies is "there's no way to know which are the ones that are at risk of obesity later on and which are the ones that are going to grow out of it," said Mark Rosenberg, a pediatrician at Children's Healthcare Associates in Chicago. That's much easier to determine when a child is 2 to 3 years old, he said.
Furthermore, "I don't think we really know what interventions are appropriate to take (to reduce weight gain) in young children. It's something that a lot of us are struggling with," Rosenberg said.
One reason so many infants are overweight has to do with a long-term trend: More are being born large for their gestational age, defined as weighing above 4,000 grams or about 10 pounds, compared with 25 years ago. It may be hard for those infants to shed fat accumulated in utero, researchers say.
Researchers say the primary factors are fewer moms who smoke (smoking is a risk factor for low-weight babies), more moms who are seriously overweight before they become pregnant, and a much higher incidence of gestational diabetes.
Nina Brooks of Matteson fits the profile. She weighed 245 pounds before becoming pregnant and developed gestational diabetes while carrying twins. When the babies were born at 38 weeks, son Lemark topped 10 pounds and daughter Laila was 9 pounds 3 ounces.
Today the 6-month-old twins are about 20 pounds each, and "my pediatrician has no concerns," Brooks said.
MaryPat Mauro of Oak Park has given birth to two really big babies: Carter, 6, who was 11 pounds, and 1-year-old Harrison, who was 10 pounds 1 ounce.
Carter's birth was exceptionally difficult, a typical complication associated with larger-than-usual infants. Often, mothers of big babies require Caesarean sections, said Dr. Maura Quinlan, assistant professor of obstetrics and gynecology at the University of Chicago.
Both of the Mauro boys remain big, though Carter has slimmed down. Harrison is the one doctors are watching. At almost 31 pounds, "he's closer to the average size of a 2-year-old," his mom said, "and we want to see what happens to his weight when he starts walking."
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© 2006, Chicago Tribune.
