Reduction in sugar-sweetened beverages is not associated with more water or diet drinks

<b>Objective</b> The Dutch Obesity Intervention in Teenagers (DOiT) is a school-based randomised controlled trial that was effective in decreasing the consumption of sugar-sweetened beverages among adolescents. The present study examined, using mediation analysis, whether this decrease in consumption of sugar-sweetened beverages could be explained by an increase in the consumption of water or diet drinks.<br /><br /><b>Design</b> Participants completed a questionnaire about their beverage consumption at baseline and at 8 months (immediately post-intervention), 12- and 20-month follow-ups. A series of multi-level linear regression analyses were performed to examine water and diet drink consumption as potential mediators of the intervention effect on the consumption of sugar-sweetened beverages.<br /><br /><b>Setting</b> Eighteen Dutch secondary schools.<br /><b><br />Subjects</b> A total of 747 adolescents (mean age: 12·7 years).<br /><b><br />Results</b> In addition to the DoiT intervention effect of a reduction in the consumption of sugar-sweetened beverages at 8 months (−284 ml/d; 95 % CI −420, −148) and 12 months (−260 ml/d; 95 % CI −360, −160), there was also a significant reduction in diet drinks at 8 months (−52 ml/d; 95 % CI −89, −16). There was no significant difference in water consumption at any follow-up. The decrease in sugar-sweetened beverage consumption could not be explained by an increase in water or diet drink consumption at any time point.<br /><br /><b>Conclusions</b> Interventions aimed at reducing sugar-sweetened beverage consumption may be effective without changing consumption of other beverages. Reducing sugar-sweetened beverages was, however, a main message of the DOiT intervention. It is possible that a concomitant promotion of water may have resulted in a greater increase in water intake and replacement of sugar-sweetened beverages with water.<br />