The answer is "no" according to this study just published in the journal ICAN: Infant, Child, & Adolescent Nutrition: Here is the abstract:
Background. School policies limiting the availability of sweetened beverages are often considered to be effective interventions for improving children’s diet and weight-related health. This study was designed to examine the effectiveness of the Rhode Island Healthier Beverage Policy in reducing consumption of unhealthy beverages and in producing changes in children’s weight status. Method. Students in 2 public middle schools in Rhode Island completed self-reported measures of dietary intake and were measured for height and weight prior to and 1 year following the implementation of a state-mandated healthier beverage policy. An inventory of beverages available in vending machines after the beverage policy was implemented provided a measure of adherence with the statewide policy. Results. Both surveyed schools demonstrated compliance with the beverage policy (ie, greater than 70% of available beverages complied). Self-reported consumption of sweetened beverages did not change significantly following policy implementation. Neither average BMI percentile for age and gender nor frequency of children in each weight category changed significantly 1 year after the policy was implemented. Conclusions. Although the healthier beverage policy was effectively implemented, it did not result in changes in self-reported sweetened beverage consumption or weight status 1 year later. Additional school policy and individual-level changes appear to be necessary to effect change in weight and dietary outcomes for children.