Allowing Soft Drinks in Schools Debated

Consumption of carbonated soft drinks from school vending machines has very little impact on adolescent weight problems, according to a report in the journal Risk Analysis.

Given that, the data does not support a policy of banning or restricting sales of soft drinks in schools, the authors conclude.

"We don't want this research to be taken to indicate that we think the problem of adolescent overweight is nonexistent or something we shouldn't pay attention to," says study author Richard A. Forshee, deputy director and director of research at the University of Maryland's Center for Food, Nutrition, and Agriculture Policy.

"We believe adolescent obesity is a very serious problem," Forshee says. "We think these kinds of analyses are necessary to help us find [the] most effective interventions so we can have a positive impact on a problem we all care about."

Soft Drinks Only Part of the Problem

Other nutrition experts argue that the study missed the larger picture.

"You're not going to be able to find one thing that is going to be the be-all and end-all in obesity in kids," says Cathy Nonas, director of the diabetes and obesity programs at North General Hospital in New York City and a spokeswoman for the American Dietetic Association.

"I don't think any one thing is going to have a strong effect, " Nonas comments.

The study was funded by the American Beverage Association. Forshee maintains that his group "followed a very rigorous scientific process" and that the association had no input into the analysis, design, interpretation, or decision to publish the research.

According to background information in the report, the percentage of adolescents classified as overweight increased from 10.5 percent in the 1988-94 period to 15.5 percent in the 1999-2000 period.

Scientists, policy makers, and concerned citizens alike are trying to find effective ways to stem the rising rates of obesity. One strategy under consideration is banning or limiting sales of soft drinks from vending machines in schools.

In January, the American Academy of Pediatrics issued a policy statement recommending that soft drink sales in schools be severely restricted, pointing out that sweetened drinks (including fruit drinks as well as soft drinks) are now the main source of added sugar in the daily diets of children.

The authors of the current study state there is little scientific evidence to support such a policy, and set out to analyze the existing literature.

To this end, they used the tool of "risk analysis," which, Forshee says, "has not been applied as widely as it should be in nutrition policy."

The idea was to apply the tool to a controversial area in nutrition policy (soft drink sales in schools) as a way to demonstrate that it might have wider utility.

Forshee used two federally funded data sets, including the National Health and Nutrition Examination Survey 1999-2000 (NHANES), and one data set from the National Family Opinion consumer research firm.

The researchers used the largest association between school soft drinks and body mass index (BMI) they could find, which was a 0.24 unit change in BMI for every one serving change in soft drink consumption.

Even using this upper-end figure, Forshee notes, "There was no statistically significant association and, in fact, regular carbonated soft drinks accounted for less than 1 percent of the variance in BMI."

Home Consumption Far Greater

Consumption of soft drinks from school vending machines was also quite low, with estimates ranging from half an ounce to two ounces per day per student. Adolescents drank five times as much at home.

The findings implied that consumption of sugar-sweetened beverages need to be cut by more than four servings a day to reduce BMI by 1 kilogram per meter squared.

With current consumption of such drinks at two servings a day for males and about one a day for females, it is unlikely that such a policy in schools will make a "meaningful difference in BMI distribution of the population," the authors write.

"We're not saying that there's no kid that has a problem with consumption with sweetened beverages," Forshee explains. "We're wondering what kind of public policy interventions are going to be effective at dealing with public health issues."

"Restricting sales of soft drinks in schools does come with some costs," he adds. "It restricts choices, and it is a source of revenue for schools."

For Nonas, however, restricting soft drink sales in schools would be part of a larger policy initiative which also would include making parks safer, more gym time in schools, reduced television watching, and getting rid of sweetened drinks at home.

"I've always said that vending machines are a start, but nowhere near enough to make a dent," Nonas says. "This, by itself, is not an effective policy. That's different from saying it shouldn't be done."

Always consult your child's physician for more information.