Childhood obesity interventions must begin early, experts say

Janet Wojcicki, PhD, MPH, UCSF assistant professor of pediatrics, and Melvin Heyman, MD, MPH, professor of pediatrics and chief of pediatric gastroenterology, hepatology and nutrition at UCSF Children's Hospital, discuss how "Let's Move" might have the greatest impact on reversing the childhood obesity epidemic in the New England Journal of Medicine. Their perspective piece is available online and will appear in the April 21, 2010, issue of the journal.

When the First Lady introduced "Let's Move" in February 2010, she outlined the campaign's central anti-obesity strategies. These include revamping the nutritional labeling of products by the U.S. Department of Agriculture, improving the nutritional standards of school lunches, increasing opportunities for children to engage in physical activity, and improving access to high-quality foods throughout the country.

According to Wojcicki and Heyman, these intervention strategies do have the potential to alter the course of the childhood obesity epidemic to some extent. However, because "Let's Move" focuses primarily on school-age children -- many of whom already are overweight or obese -- the program in its current form does not constitute a truly comprehensive obesity intervention plan.

"These types of behavioral and nutrition interventions in schools or within the home have only limited success in preventing weight gain in children," the authors say. "Obesity prevention must start as early as possible, since school-age children already have an unacceptably high prevalence of obesity and associated medical conditions."

The authors cite the 2007-2008 National Health and Nutrition Examination Survey, which found that nearly one-third of American children two years and older are overweight or obese, and even higher proportions among low-income children and ethnic minorities.

With those numbers in mind, Wojcicki and Heyman assert that in order to have the greatest impact, "Let's Move" must include prevention efforts that directly target pregnant women, infants and pre-school-age children.

"Including prevention efforts for these groups will have the longest-term effect on the obesity epidemic in the United States," they say.

For example, Wojcicki and Heyman recommend that "Let's Move" incorporate interventions that aim to reduce weight gain and cigarette smoking in mothers-to-be. Studies have shown that excessive weight gain and smoking during pregnancy each are associated with an increased risk for obesity later in life.

The authors also advocate for interventions designed to increase the amount of time infants are breastfed and the amount of sleep babies get, as shorter-than-recommended durations of breastfeeding and suboptimal amounts of sleep also put a child at greater risk for becoming obese. According to Wojcicki and Heyman, these types of interventions are crucial to include in a comprehensive obesity prevention effort, because they affect a child's lifetime risk of obesity.

"By directly emphasizing the potential risks for lifetime obesity that present in infancy and early childhood and providing the structure and direction for interventions in these areas, the campaign could increase its overall impact on reversing the childhood obesity epidemic," they conclude.

Wojcicki currently is investigating pre- and post-natal factors that might shape future dietary habits and the development of obesity in a group of Latino families. The children are entering their third year of life, and already Wojcicki and her team of researchers at UCSF have found patterns of eating behavior that may lead to future weight problems. Wojcicki's research is supported by funding in part from the NIH and from philanthropic support.