fruits and vegetables, and preferences in turn were associated with fruit/vegetable intake (Neumark-Sztainer et al., 2003).
This section considers the evidence relevant to the influence of marketing on diet-related health. For marketing to influence young people’s diet-related health, it must influence their diet, as depicted in the five-element causal framework (see Figure 5-1) that guided the systematic evidence review. Elsewhere in this report (see Chapter 2 and Appendix D), evidence that links diet to health has been presented. Here, consonant with the committee’s charge, research that includes marketing as a possible causal factor and diet-related health as an outcome is reviewed and assessed. Such research could address any of the four major marketing elements (product, place, price, and promotion) as an influence on juvenile health outcomes such as weight, obesity, cholesterol, and type 2 diabetes. In point of fact, some research has included marketing as a consideration, but little research has intentionally focused on any aspect of the relationship of marketing to diet-related health. As noted previously, the committee acknowledges that various factors in addition to food and beverage marketing might affect this relationship, but these are not the direct subject of the committee’s inquiry and therefore the focus here is on the specific relationship of marketing to diet-related health.
The committee identified a substantial body of research that is relevant to understanding the relationship of marketing to diet-related health. These studies examined the relationship between television viewing and diet-related health, almost always juvenile adiposity. Sixty-five articles that examined this relationship were identified and included in the systematic evidence review. All but one study (Robinson, 1999) employed a correlational design, gathering data at either one or two points in time to examine the relationship between amount of television viewing and diet-related health. One study (Wong et al., 1992) examined cholesterol levels; one study (Guillaume et al., 1997) examined cardiovascular fitness and adiposity; all the rest examined adiposity. Most studies also measured some possible moderating variables such as age, race/ethnicity, or socioeconomic status or some possible alternative explanatory variables such as activity level or snacking while viewing television. Nearly all employed various statistical controls to better elucidate the underlying causal mechanisms accounting for any significant association of television viewing and diet-related health.
After careful consideration, the committee judged that it was reasonable to include these studies in the systematic evidence review for the rela-