One target behavior of interest for interventions is the consumption of sugar-sweetened beverages (SSBs). Although sodas (carbonated beverages) are usually seen as the primary SSBs, the category also includes sports drinks and a large number of colas and fruit-flavored beverages which are not carbonated, but nevertheless contain large amounts of added sugar. The consumption of both types of SSBs by children has increased dramatically in the past few decades. Between 1977 and 1998, the prevalence of daily SSB consumption among children aged 11–18 years nearly tripled⁹, while the amount of SSB intake per day in this population more than doubled¹⁰. Adolescents now derive 10–15% of their total caloric intake from the consumption of SSB¹¹. Because these increases have occurred concomitantly with rising levels of childhood overweight and obesity across the population, several scholars theorize that SSB consumption may be an important driver of the obesity epidemic^{12, 13}. Several individual-level cross-sectional and cohort studies confirm an association between soft drink consumption and BMI or weight gain^{14, 15}.

Nevertheless, only a small number of interventions have explicitly targeted SSB consumption as a primary outcome¹⁶. SSB interventions that have been successful tend to be characterized by environmental alterations, such as home delivery of non-caloric beverages to displace SSBs¹⁷, or the installation of water fountains in schools¹⁸. There is a need to develop more feasible behaviorally-based interventions. An important knowledge gap in this regard is the absence of information regarding the behavioral context of SSB consumption among adolescents. Little is known about the dietary and activity correlates of SSB consumption, and whether these behavioral correlates are similar across different categories of SSBs in this age-group. Several studies have reported that SSBs displace milk consumption^{19, 20} and one small study showed reduced fruit consumption and increased calorie consumption associated with high levels of SSB consumption²¹, but apart from these data, little is known about foods that are either complementary to or negatively associated with SSB consumption. Similarly, there is little published work examining if SSB consumption is associated with specific patterns of physical and/or sedentary activity. Knowledge of dietary and activity correlates, and how they differ across broad subgroups of beverages, is clearly relevant in informing the design of broad-based behavioral interventions targeting SSB consumption among adolescents.

The primary purpose of this study is to examine the dietary and activity correlates of SSB consumption among adolescents. Data for the study are obtained from the School Physical Activity and Nutrition (SPAN) surveys conducted by the University of Texas School of Public Health and funded by the Texas Department of State Health Services in the state of Texas in 2004–2005²². The size of the dataset (n=15,283), the substantial representation of key racial and ethnic categories, and the age groups represented (8^th and 11^th grade) all make these data particularly suited to these analyses.

We hypothesized that SSB consumption co-occurs with specific dietary and activity behaviors for children at these ages, such that the extent of each of these behaviors would vary systematically across levels of SSB consumption. We further presumed that these behaviors vary by gender, as a number of studies have shown sex differences in the level of SSB consumption as well as in possibly associated dietary behaviors^23–25. Finally, we hypothesized that the behavioral correlates of SSB consumption vary with the type of SSB consumed, specifically, regular sodas and flavored and sports beverages (FSB), because of differences in how consumers perceive these two categories. The analysis is limited to 8^th and 11^th grade children as younger children typically have lower control over the acquisition of beverages or the context of beverage consumption.

Several findings are noteworthy. First, when total SSB (both regular sodas and flavored and sports beverages) is considered, the prevalence of SSB consumption among these children is very high, with 28% of children consuming three or more SSBs a day. Second, the amount of SSB consumption varies by socio-demographic characteristics as well as by type of SSB. Third, the study is the first to demonstrate pronounced and consistent associations of a variety of dietary and activity behaviors with the level of SSB consumption. Fourth, these associations vary substantially and systematically by the type of beverage considered.

The high level of consumption of sugar-sweetened beverages among adolescents has generated considerable concern because of its potential to increase weight gain. It has been estimated that daily consumption of just 1 12 oz. can of soda or other SSB could lead to as much as 15-lb weight gain in a year²⁸. In light of this, our findings relating to the high prevalence and level of soda and other SSB consumption among 8^th and 11^th grade children are troubling. Approximately 10% of these children report consuming three or more sodas on the previous day. Average consumption of SSBs across all children is about 1.6 servings per day; this is likely an underestimate, as the questions relating to consumption were top-coded at 3, and do not include other beverages such as energy drinks or sweetened milk drinks, which frequently contain high levels of sugar.

The findings relating to differences in level of consumption by socio-demographic category have important implications for the development of interventions. Boys consume higher levels of SSB than girls, and soda consumption in particular increases with grade level among boys. African-Americans consume soda at lower levels than Hispanics or Whites, but their level of FSB consumption is substantially higher. Soda consumption increases with economic disadvantage among females, but less so among males. Different patterns of SSB consumption among different demographic subgroups, especially across racial/ethnic categories, can and should be accommodated in efforts to tailor interventions.

Our most important findings relate to the difference in behavioral correlates of FSB and soda consumption. Both soda consumption and FSB consumption are positively associated with various unhealthy dietary practices and sedentary behaviors, suggesting that these practices may be universal in the adolescent population. However, there is clear divergence between the two categories of SSBs with regard to the consumption of healthy items, such as milk, fruit and vegetables, with FSB showing a positive association and sodas showing a negative association. Similarly, physical activity increases with level of FSB consumption but decreases with level of soda consumption. The most likely explanation for these findings is that FSBs have been successfully marketed as beverages consistent with a healthy lifestyle, to set them apart from sodas. Often, these beverages contain a minimal percentage of fruit juice, or more commonly, contain artificial fruit flavors, conveying the impression that the drink is more healthful than it actually is. This may explain our finding that the behavioral correlates of FSB consumption are very similar to those of fruit juice consumption, while remaining distinct from the correlates of soda consumption. Thus, it is apparent that consumers differentiate between sodas and the sports and flavored drink groups. This product differentiation between sodas and FSB has not been made by public health advocates and scholars, who focus instead on the fact that all these beverages are sugar-sweetened^{13, 15, 29}. While this approach is consistent from a physiological point of view, our findings clearly underscore its inadequacy as a paradigm for informing analyses as well as the development of interventions. Analyses that examine sugar-sweetened beverages as a single category mask the differential behavioral associations with categories of SSB. Recognition of the different behavioral contexts of different categories of SSB needs to be an important input in intervention design, as well as in assessment of SSB consumption.