The energy density of foods is higher for snacks compared to meals (Jahns et al., 2001). Based on the 1994–1996 and 1998 CSFII, children 3–5 years of age ate snacks averaging 146 ± 3 calories, children 6–11 years of age ate snacks averaging 197 ± 5 calories, and adolescents aged 12–19 years ate snacks averaging 274 ± 11 calories (Huang et al., 2004).
Studies of the effects of children’s consumption patterns on parents restricting energy-dense foods suggests that severe restriction of preferred foods of low nutrient value may increase their desire for such foods (Benton, 2004; Fisher and Birch, 1999). Taste perception is likely another important factor in food choices (Drewnowski, 1997). Factors that determine taste preference include genetic background (Birch, 1999; Mennella et al., 2005) and early life exposure (Birch, 1998; Birch and Fisher, 1998; Mennella et al., 2006). Because schools represent only a small part of the daily eating opportunity for children it is not clear whether restriction of energy-dense foods of minimal nutritional value in the school environment will encourage school-age children to consume them.
Studies of students’ perceptions of factors influencing food choices suggest that they are open to information about healthful choices and willing to make changes to improve their diets. O’Dea (2003) studied the responses of students aged 7–17 years to suggested strategies to overcome barriers to healthful eating. This study found that children and adolescents were willing to make healthful behavior changes and looked to parents and teachers for support. Neumark-Sztainer et al. (1999) assessed perceptions of factors that affect food choice behaviors among adolescent boys and girls from inner-city schools. From focus group discussions, the study identified a broad range of factors such as hunger, taste appeal, availability, and convenience that influence food choice behavior. The study concluded that knowledge of these factors could be useful in developing ways to make healthful food more appealing to adolescents and encourage healthful behaviors.
Gender differences in dietary intakes emerge as children move into adolescence. During childhood, food intakes of girls and boys tend to be similar. Because of increased rates of growth and body size, adolescent males eat larger quantities of food on average than female adolescents, so they are more likely to meet recommended daily intakes for vitamins