Improving literacy about energy-related issues: the need for a better understanding of the concepts behind energy intake and expenditure among adolescents and their parents.

Despite the need for effective obesity prevention strategies, little research has assessed adolescents' knowledge about basic concepts of energy intake, expenditure, and balance. Using data from 349 adolescent-caregiver pairs (recruited from Minneapolis/St Paul, MN metro region, 2006-2007), cross-sectional linear regression was used to assess adolescent and parental knowledge related to energy intake and expenditure as a predictor of adolescent weight-related behaviors and outcomes. Findings indicated that knowledge related to energy intake and expenditure was highly variable, with a substantial proportion of participants (particularly adolescents) lacking knowledge on a range of concepts. Adolescent knowledge was positively associated with moderate physical activity and negatively associated with television viewing (P<0.05), but it was not associated with sweetened beverage consumption, fast food intake, weight status, and/or body composition. Although overall parental knowledge was a significant predictor of adolescent knowledge (P<0.01), parent-child agreement on individual items was poor. As adolescents age, low literacy in this area may set the stage for poor decision-making related to energy balance and healthy weight maintenance. However, in that knowledge was not a significant predictor of various weight-related outcomes, these and other findings suggest that purely education-based health promotion strategies are insufficient to initiate long-term healthful behavior change. Educational strategies may be effective when combined with those also targeting familial, social, and environmental influences. The examination of interactive effects between individual-level and environmental influences on health behavior is an important area for future obesity-related research.