Purpose-To test self-regulation concepts in relation to dietary intake and physical activity patterns in adolescence, which we predicted to be influenced by components of a self-control model.Methods-A survey was conducted with a multiethnic sample of 9th grade public school students in a metropolitan area (N = 539). Confirmatory analysis tested the measurement structure of selfcontrol. Structural equation modeling tested the association of self-control constructs with measures of fruit and vegetable intake, saturated-fat intake, physical activity, and sedentary behavior.Results-Confirmatory analysis of 14 indicators of self-control showed best fit for a two-factor structure, with latent constructs of good self-control (planfulness) and poor self-control (impulsiveness). Good self-control was related to more fruit and vegetable intake, more participation in sports, and less sedentary behavior. Poor self-control was related to more saturated-fat intake and less vigorous exercise. These effects were independent of gender, ethnicity, and parental education, which themselves had relations to diet and exercise measures. Multiple-group modeling indicated that effects of self-control were comparable across gender and ethnicity subgroups.Conclusions-Self-control concepts are relevant for patterns of dietary intake and physical activity among adolescents. Attention to self-control processes may be warranted for prevention programs to improve health behaviors in childhood and adolescence. Keywords self-control; diet; exercise; adolescents; gender; ethnicity Epidemiologic data have drawn increasing attention to diet and exercise patterns among young persons. Between 1980 and 2002, the prevalence of obesity in the US has doubled among adults and tripled among children and adolescents [1]; similar patterns have been observed in other countries [2]. Obtaining a better understanding of patterns of dietary intake and physical activity has public health significance because excess weight and inadequate exercise have been linked to increased morbidity from several diseases. The magnitude of increases in weight in the population of young persons has indicated a need for new approaches to weight-related behavior [3,4], and research conducted in adolescence provides an opportunity to study the origins of these behavioral patterns. Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. The present research was based on a self-control model as a theoretical approach to understanding health behavior patterns. For substance use, theoretical papers have outlined how behavioral and emotional regul...