Field Notes

Web-Based Intervention Appears Ineffective for Preventing Weight Gain in Adolescents

A Web-based, computer-tailored intervention aiming to increase physical activity, decrease sedentary behavior, and promote healthful eating among adolescents wasn’t associated with positive long-term outcome measures but may have positive short-term effects on eating behaviors, according to a report published online in the Archives of Pediatrics & Adolescent Medicine.

"The high prevalence of overweight and obesity among adolescents is a major public health concern because of its association with various chronic diseases," the authors wrote as background information in the article. "Computer tailoring has been recognized as a promising health communication technique to promote energy balance-related behaviors."

To evaluate the short- and long-term effectiveness of a Web-based, computer-tailored intervention on preventing excessive weight gain in adolescents, Nicole P. M. Ezendam, PhD, then of Erasmus University Medical Center in Rotterdam, the Netherlands, now of Tilburg University in Tilburg, the Netherlands, and colleagues developed the online, school-based FATaintPHAT intervention. The intervention included 20 schools in the Netherlands and a total of 883 students aged 12 to 13. The main objectives of the intervention were to improve dietary habits (including reducing the consumption of sugar-sweetened beverages and increasing fruit, vegetable, and whole grain intake), reduce sedentary behavior, and increase physical activity. Students not meeting behavioral guidelines at the start of the study were considered at risk.

The FATaintPHAT intervention included eight modules that addressed issues of weight management and energy balance behaviors. Each module contained information about the behavior-health link, an assessment of behavior, individually tailored feedback on the behavior, and an option to formulate an implementation intention to prompt specific goal setting and action planning.

The complete analysis showed no intervention effects on BMI, waist circumference, or the percentage of students being overweight or obese in the total sample. At the four-month follow-up, students in the intervention group were less likely to report drinking more than 400 mL of sugar-sweetened beverages per day compared with students in the control group in the total sample but not in the at-risk group. Average self-reported snack consumption was lower in the intervention group than in the control group at the four-month follow-up; however, the difference wasn’t statistically significant at the two-year follow-up.

Among the students at risk, those in the intervention group reported eating more pieces of fruit than those in the control group at the four-month follow-up. Students in the intervention group also reported eating more grams of vegetables per day than those in the control group for both the total sample and among at-risk students. There were no differences in the self-reported consumption of whole wheat bread between the intervention group and the control group. An inverse relationship was observed for students in the intervention group, as at-risk students in the intervention group were less likely to report participating in sports at the four-month follow-up than students in the control group.

"The FATaintPHAT intervention was associated with positive short-term effects on diet but with no effects or unfavorable effects on physical activity and sedentary behavior," the authors wrote. "In conclusion, our study shows that the computer-tailored intervention FATaintPHAT wasn’t effective in modifying anthropometric outcome measures but that it can have a positive effect on dietary behaviors among adolescents at short-term follow-up."

— Source: American Medical Association


Future Obesity May Be Predicted at Young Age

Researchers can predict which children are most likely to become obese by examining their mothers' behavior around their birth, according to a recent University of Montreal study published in the Archives of Pediatric and Adolescent Medicine.

“Although behavior is extremely hard to change and is also influenced by a complex tangle of influencing factors in the environment, I hope these findings will help improve the social and medical services we offer to mothers and infants,” said lead author Laura Pryor, a PhD candidate in the university’s department of social and preventive medicine. The findings come as the province of Quebec, like other societies, grapples with a surge in childhood obesity over the last generation.

Pryor and the study team analyzed data drawn from the Quebec Longitudinal Study of Child Development that ran from 1998 to 2006. The team focused on 1,957 children whose height and weight measurements had been taken yearly, from the age of 5 months to 8 years old, and recorded in a database. This information enabled the team to look at the development of the children’s BMI. The researchers identified three trajectory groups: children with low but stable BMI, children with moderate BMI, and children whose BMI was elevated and rising, called high-rising BMI.

"We discovered the trajectories of all three groups were similar until the children were about 2 1/2," Pryor says. "Around that point, the BMIs of the high-rising group of children began to take off. By the time these children moved into middle childhood, more than 50% of them were obese according to international criteria."

Researchers found two factors that may explain this: the mothers' weight around the time they gave birth and whether the mothers smoked. A child with a mother who was overweight or who smoked during pregnancy was significantly more likely to be in the high-rising group. These two factors were found to be much more important than the other criteria that were studied, such as the child’s birth weight.

The risk factors identified here represent increased probabilities of becoming overweight, not direct causes. More research will be required to determine how these early-life factors and others are correlated with childhood obesity.

"Our research adds to the growing evidence that the perinatal environment has an important influence on later obesity,” Pryor says. “This points to the need for early interventions with at-risk families in order to prevent the development of childhood weight problems and the intergenerational transmission of ill health. I would like to conduct further studies to find out what happens to these kids once they reach adolescence, and I hope that my research will help in the development of strategies to combat this serious public health issue."

— Source: University of Montreal