Free sugars intake plays a major role in dental caries formation and other general health issues such as obesity. Therefore, interventions, which assist individuals or populations in the control of their free sugars intake, are of central importance in caries prevention strategies. There is good evidence that behavioral interventions benefit from a foundation in conceptual theories of behavior change founded on empirical data. In this review, we discuss the future application of seven theories, including six common psychological theories in predicting and developing interventions to reduce free sugars intake related to dental caries among adults. For each model, we summarize its key features and the data derived from its application in general and oral health settings and make recommendations for future research. We searched Medline, PsycINFO, Global Health, PubMed, and Embase databases to identify items dealing with dental caries, adults, sugars intake, and six psychological theories. These included the Transtheoretical Model of Change, Theory of Planned Behavior, Social Cognitive Theory, Information-Motivation-Behavioral Skills model, PRIME Theory, and Behavior Change Wheel theories. We searched literature published in the last 10 years, and priority was given to systematic reviews and randomized control trials. Although there is extensive literature on the application of the six psychological theories, there is a gap in knowledge about their effectiveness in reducing free sugars intake related to dental caries among adults. There is a need for better-designed trials of interventions based on the clear operationalization of psychological constructs to reduce sugars intake among the adult population.