Adolescents and young adults adopt eating patterns which may well form the basis of their dietary habits for much of their lives. At the same time, this section of the population can come under considerable pressure from the world at large, to conform to the current trends in fashion, language, behavior, or foods. Recent developments in Western dietary practice have tended to leave adolescents vulnerable to low intakes of energy and of some nutrients, as snacking accounts for an increasing proportion of dietary intake. Achieving a balanced diet is more difficult when the most popular and widely available snack foods are high in sugar or in fat. Results from major British studies, together with a review of data from other developed countries, support the need for more effective dietary education for adolescents and for children generally.