Transtheoretical model-based nutritional interventions in adolescents: a systematic review

Abstract

Background Literature has shown a tendency of inadequate dietary intake among youth, consequently, nutritional interventions are required. The transtheoretical model (TTM) classifies individuals based on their readiness to change. This model is widely used for health education interventions with proven efficacy. Purpose This review aimed to weigh the strength of evidence about the TTM usage in nutritional interventions for adolescents and its effectiveness regarding dietary intake. Methods This study followed the PRISMA guidelines. Eligible studies were input into Mendeley software. The Adolec, Google Scholar, LILACS, PsycINFO, PubMed, Science Direct and Web of Science databases were searched. Only full original articles written in English, Spanish or Portuguese on randomized controlled trials and quasi-experimental designs that applied the TTM in the design of nutritional interventions targeting adolescents were included, with no restrictions on publication date. The quality and risk of bias was evaluated with the Effective Public Health Practice Project Quality Assessment Tool for Quantitative Studies. Results The initial search yielded 3779 results. Three studies were rated as strong, six as moderate and five as weak. The final sample of 14 articles included adolescents that were mostly recruited from schools, with interventions ranging from one month to three years. The TTM was used alone or combined with other behavior-change theories and most of the interventions involved digital technology. The nutritional topics covered included fruit and vegetable consumption, low-fat diet, and cooking skills. Four studies presented improvement in fruit and vegetable consumption and four progressed through stages of change. Participants from two interventions reduced fat intake. At the end of one intervention, all the participants were in action and maintenance stages. Conclusion The TTM seems to be a successful strategy for nutritional intervention aiming at improving dietary intake in adolescents. Its application in different contexts shows that the TTM is flexible and possible to be implemented in many settings. The use of the model is shown to be restricted to the stage of change’ construct. Further studies should use all constructs of the TTM in the design and compare the TTM with other behavior-change theories to better understand its effectiveness.

Theoretical constructs of smoking cessation among current tobacco smokers in India: a secondary analysis of Global Adult Tobacco Survey-2 (2016–2017)

“…The TTM model used in the study has aptly proved that smokers not only perceive more benefits as they move in later stages but are also being influenced by a different set of determinants for smoking cessation. This view has been supported by other studies on physical activity, 31 sedentary behaviour, 32 nutritional interventions, 33 etc. The TTM’s ability to customise its constructs to an individual’s readiness to initiate cessation behaviour is a major strength, making individually based interventions applicable at the population level.…”

Effect of a 1-Year Controlled Lifestyle Intervention on Body Weight and Other Risk Markers (the Healthy Lifestyle Community Programme, Cohort 2)

“…During the seminar breaks (∼15 min), healthy snacks were provided (first by the research team, then increasingly by the participants), for example, whole-grain bread with plant-based spreads, salads, fruit, nuts, etc. Seminar topics included causes and development of lifestyle-related diseases, risk factors, lifestyle choices, and behaviour change (based on Prochaska’s model of change [26, 41] and transtheoretical model [42, 43]). The seminars also included practical interactive sessions (∼10–30 min; for example, cooking, exercise, meditation, and group work).…”

Impact of a School-Based Gardening, Cooking, Nutrition Intervention on Diet Intake and Quality: The TX Sprouts Randomized Controlled Trial

“…The model assumes that changes in habitual behaviors occur continuously through a specific process [ 80 ]. Additionally, research in adolescents suggests that interventions focusing on intake of specific dietary components show better results [ 81 ]. This may explain why we found improvements in vegetable and added sugar consumption, as these were key focus areas of the TX Sprouts intervention but did not see changes to other aspects of the diet with the exception of protein as a percent of total energy.…”