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Here's some worrying news for parents. The risk of becoming obese seems to start even earlier than we thought. By kindergarten, many kids look like they're already well on their way to obesity. That's according to a big new study released today by the New England Journal of Medicine. NPR's Rob Stein reports.
ROB STEIN, BYLINE: Everyone knows the childhood obesity epidemic is a problem, but Solveig Cunningham of Emory University wanted to see just how early in a child's life the warning signs emerge.
SOLVEIG CUNNINGHAM: This would be a really important thing to focus on and to understand because it lets us know about the ages of vulnerability, when does obesity occur, and who might be at greatest risk.
STEIN: So Cunningham and her colleagues followed more than 7,000 kids when they started kindergarten. They wanted to see who ended up becoming obese by the time they got to middle school. And they found something really disturbing.
CUNNINGHAM: Kids who started off kindergarten overweight actually had about four times greater risks of becoming obese by eighth grade compared with normal-weight kindergartners.
STEIN: A lot of parents like to think their kids will just grow out of their baby fat. But this says that's often not the case. In fact, almost half of all the kids who had become obese by eighth grade were the ones who already were considered overweight in kindergarten.
CUNNINGHAM: One major implication is that the risks for obesity are in part set fairly early in life. So as parents, as a society, as clinicians, we need to think about healthy weight really early on.
STEIN: Really early on meaning even during when a woman is pregnant. The same study found one-third of the kids who ended up being obese by eighth grade were the ones who were on the large side at birth. David Ludwig is a childhood obesity expert at Boston Children's Hospital.
DR. DAVID LUDWIG: A key time period appears to be both pregnancy - a time when the fetus is growing and developing and biological pathways are being established - and also the first few years of life. So maternal diet, maternal weight gain and the infant's diet during the first few years may have an outsized influence on long-term risk for obesity and related diseases.
STEIN: So Ludwig says women have to be careful not to gain too much weight while they're pregnant and do commonsense things during their kids' first few years of life. Make sure their kids don't sit around too much watching TV and playing video games, get them plenty of exercise, and watch what they eat.
LUDWIG: Importantly, avoiding excess consumption of all of the refined carbohydrates that have snuck in our diet over the last few decades - the sugary beverages, too much fruit juice, and all of the processed, packaged snack foods.
STEIN: But some experts worry the new research will cause some parents to overreact at any sign their babies or toddlers are getting a little chubby. Joanne Ikeda is a nutritionist at the University of California, Berkeley.
JOANNE IKEDA: Putting them on a calorie-restricted diet can stunt their growth in height. So you don't want to put children on a calorie-restricted diet. What you want to do is help them have healthier lifestyle habits and they will grow into their weight.
STEIN: Others worry the research will add more fuel to what they think is a kind of hysteria around childhood weight. Linda Bacon of the University of California, Davis says kids are already suffering.
LINDA BACON: What this is going to do to kids is it's going to cause more bullying and teasing of the larger kids. It's going to cause them to feel bad about their bodies. It's going to make the thinner kids really scared of getting fatter.
STEIN: The researchers behind the new study are not advocating putting young children on diets or making them feel bad about their weight. They just hope their work will help discourage the bad habits that are driving the childhood obesity epidemic. Rob Stein, NPR News.
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