Preventing childhood obesity by reducing consumption of carbonated drinks: Cluster randomised controlled trial
Article Outline
James J, Thomas P, Cavan D, Kerr D. BMJ 2004;328:1237-42
Context Obesity in children seems to be related to the consumption of sugar-sweetened carbonated drinks.
Objective To determine if a school-based educational program aimed at reducing consumption of carbonated drinks can prevent excessive weight gain in children.
Design Cluster randomized controlled trial.
Setting Six primary schools in southwest England.
Participants 644 children aged 7-11 years.
Interventions Focused educational program on nutrition throughout one school year.
Main outcome measures Drink consumption and number of overweight and obese children.
Results Consumption of carbonated drinks over 3 days decreased by 0.6 glasses (average glass size 250 ml) in the intervention group but increased by 0.2 glasses in the control group (mean difference 0.7; 95% CI, 0.1-1.3). At 12 months the percentage of overweight and obese children increased in the control group by 7.5% compared with a decrease in the intervention group of 0.2% (mean difference 7.7%, 2.2-13.1).
Conclusions A targeted, school based education program produced a modest reduction in the number of carbonated drinks consumed, which was associated with a reduction in the number of overweight and obese children.
Comment While multivariable intervention programs have shown minimal effects on rates of obesity,1., 2. this study focused on a single variable, the consumption of carbonated beverages, and its effect on obesity. Although the results of this intervention showed modest changes in soda consumption, there did appear to be a notable reduction in the number of obese and overweight children. There were several limitations to this study. Although the classes within a school were randomized, there was a risk of cross-contamination between classes. There may be some response bias, as only a small percentage of diaries were completed (36%). The authors addressed this, noting that the rates of obesity were the same in responders and nonresponders. They also state the baseline consumption of soda was the same in the two groups. The fact the diaries were only collected for a three-day period further limits the results, as this may not be a true indicator of the child's average soda consumption.
Despite these limitations, this study provides hope that interventions targeting single variables may be successful in limiting obesity, and it draws our attention to the significant contribution soda consumption has on childhood obesity. Parents and schools may be overwhelmed with messages regarding diet, nutrition, and exercise. This intervention gives parents and children a specific goal, to decrease soda consumption, with the benefit of weight reduction. The fact that this intervention requires little teacher or school training and can be provided with relative ease makes it even more appealing.
References
PII: S0022-3476(04)00754-1
doi:10.1016/j.jpeds.2004.08.035
© 2004 Elsevier Inc. All rights reserved.
