It is widely assumed in academic and policy circles that younger children are more influenced by advertising than are older children. By reviewing empirical findings in relation to advertising and children’s food choice, it is argued that this assumption is unwarranted. The findings do not suggest that young children are more affected by advertising than are teenagers, even though the latter are more media literate. This article critically examines the theoretical gap in the literature regarding the relationship between advertising literacy and advertising effects. By applying a dual process model of cognitive persuasion, it is shown that the evidence is more consistent with the argument that different processes of persuasion are effective at different ages, precisely because literacy levels vary with age. Recommendations for future research on the effects of advertising on children, together with the implications for policies of regulating advertising to young children and of media literacy interventions, are identified.