Recently, a group of retired military officers who call themselves "Mission: Readiness" released a report claiming that childhood obesity has become "a national security threat," as more than a quarter of young Americans ages 17 to 24 are too overweight for military service. Sharing the concerns raised by first lady Michelle Obama, who has her own campaign to promote nutrition and healthy practices among youth, these ex-military men called on Congress to pass legislation aimed at improving school lunch programs and providing school-based resources to combat obesity. U.S. News asked William Dietz, a medical doctor and pediatrics expert who directs the Centers for Disease Control and Prevention's Division of Nutrition, Physical Activity and Obesity, to discuss the nation's problems with childhood obesity and what parents can do to encourage healthy choices by their children. Excerpts:
How serious is childhood obesity in America right now?
I would say it's a highly significant problem. About 17 percent of children and adolescents are affected. As they grow into adulthood, we can anticipate that, if obesity persists, then every major system in the body is affected. We also know that about 10 percent of the national healthcare budget is spent on obesity and its related problems. It's quite clear that, if we don't control obesity, we're going to have a hard time controlling medical costs more generally.
What will be the future costs of obesity?
We don't have those projections. We know that currently it's about $150 billion a year.
Is the rate of childhood obesity increasing?
Interestingly enough, the trends in obesity are pretty flat in children and adolescents. In other words, there has not been a statistically significant increase between 1999 and 2008, based on national survey data. The only increase—and this is a concern—is in severe obesity among 6- to 19-year-old boys. Overall, we can't count that as a success. We still run the risk of all these children and adolescents going on to become obese adults. What we know from the natural history of obesity is that if an obese child becomes an obese adult, his or her obesity is more severe in adulthood.
Are genetics or lifestyle more to blame?
Genetics certainly play a role but, in my view, genetics account for an increase in susceptibility. What has caused the obesity epidemic is an environment that promotes inactivity and increased food intake. The people who are going to be most responsive to that environment are going to be those who have a genetic susceptibility.
What has research shown to be the most effective weight-loss solutions for young people?
Data show that intensive efforts focused on nutrition and physical activity seem to be effective in reducing weight in children. The problem is that our capacity for treatment is limited. For mild obesity, we think that primary-care physicians play an important role. But for severe obesity, tertiary-care centers are really very important, and I think it's fair to say that we still don't understand what constitutes optimal treatment for severely overweight children and adolescents.
Do studies show any correlation between socioeconomic status or ethnicity and childhood obesity?
Well, ethnicity is the easy answer. We know that obesity is more prevalent among African-American girls and Mexican-American boys. Right away, that suggests that there are cultural factors at work, and exactly what those are or how they operate is unclear. We need to be sensitive to those disparities.
What can parents do about obesity?
What we know is that some factors that influence early childhood obesity begin during pregnancy. We know that pre-pregnant weight, excessive weight gain during pregnancy, tobacco use during pregnancy, and diabetes during pregnancy, all contribute to early-childhood obesity. The earliest decision that parents make with respect to interaction with children has to do with their choice of feeding in the newborn period. We know that breast-feeding reduces the likelihood of childhood obesity, both in terms of breast-feeding initiation and duration. We think that there are five additional strategies besides breast-feeding that are pretty important. These include increased fruit and vegetable intake because fruits and vegetables are very filling. Reduced sugar-sweetened beverage intake is another important strategy. There's been a study published that suggests that over 230 calories a day could be saved if children switched from drinking a sugar-sweetened beverage to water. Reduced high-energy-density food, like snacks and fast foods, are an important strategy. And finally, reduced television time, and particularly keeping televisions out of children's bedrooms. Now the other important strategy for obesity control is physical activity. Physical activity helps to prevent obesity, but the other important characteristic of physical activity is that it reduces the risk factors associated with childhood obesity. Parents have a very important role in making sure that children are offered healthful choices.