The Effect of Message Framing in Promoting the Mediterranean Diet: The Moderating Role of Eating Self-Efficacy

Communication Intervention to Improve Young Adults' Food Safety Practices: The Benefits of Using Congruent Framing

Background/Objectives: Improving food safety practices among young adults is critical to public health, but effective communication strategies are under-researched. This study investigated the effectiveness of a 12-day message-based intervention to promote safe food handling practices using a randomised controlled trial. Methods: A total of 588 participants (aged 18 to 35 years) were randomly assigned to one of four experimental conditions or to a control group. Participants in the intervention groups received daily messages via a mobile app, while the control group received no messages. The intervention combined belief-based content to raise awareness with skill-based content to teach practical food handling, framed by either positive or negative emotional appeals. The experimental conditions differed in message congruence, with belief-based and skill-based content framed either consistently (both positive or both negative) or inconsistently (one positive, one negative). To assess the impact of the intervention, self-reported adherence to food safety practices, food safety awareness, and self-efficacy were measured at baseline and post-intervention. Results: The results showed that the intervention significantly improved food safety practices, especially when the messages were congruent in valence. Pre-intervention self-efficacy moderated the effects, with higher self-efficacy increasing receptivity to certain messages, while lower self-efficacy benefited from a different framing. Self-efficacy, but not awareness, mediated behaviour change, highlighting its key role in the success of the intervention. Conclusions: These results emphasise the importance of message valence congruence and individual self-efficacy levels in designing effective food safety interventions. Future research should investigate long-term intervention effects, adaptive mHealth strategies, and tailored communication approaches to maximise engagement and sustained behaviour change.

Does Sex Matter in the Link Between Self-Efficacy and Mediterranean Diet Adherence in Adolescents? Insights from the EHDLA Study

Background/Purpose: To our knowledge, no previous study has analyzed the associations between self-efficacy and adherence to the Mediterranean diet (MedDiet) in adolescents, nor have sex-based differences in this relationship been examined. The aim of the current study was to examine the relationship between self-efficacy and MedDiet adherence in Spanish adolescents. Methods: This research was cross-sectional and involved 619 adolescents (56.5% girls) who were part of the Eating Habits and Activities of Daily Living (EHDLA) project. Self-efficacy was assessed using a 10-item scale (general self-efficacy scale), which yielded scores ranging from 20 to 100 points. The Mediterranean Diet Quality Index for Children and Adolescents (KIDMED), which consists of a 16-item questionnaire with scores ranging from -4 to 12, was used to evaluate adherence to the MedDiet. Unhealthy behaviors related to the MedDiet were assigned a score of -1, whereas healthy behaviors received a score of +1. Results: Overall, for each 20-point increase in self-efficacy, boys had a greater non-significant likelihood of having optimal MedDiet adherence (1.33%, 95% confidence interval [CI] -5.15 to 7.82, p = 0.687). Conversely, girls had a greater significant likelihood of having optimal MedDiet adherence per further point in self-efficacy (7.40%, 95% CI 2.28 to 12.53, p = 0.005). Individually, among boys, a 20-point increase in self-efficacy was associated with a 4.8% higher probability of having a dairy product for breakfast (95% CI 0.2 to 9.4, p = 0.042). Among girls, the same increase in self-efficacy was linked to a greater probability of consuming fruit or fruit juice daily (6.8%, 95% CI 2.2 to 11.4, p = 0.004), eating a second fruit every day (8.6%, 95% CI 3.4 to 13.8, p = 0.001), consuming fish regularly (6.2%, 95% CI 1.1 to 11.2, p = 0.017), enjoying pulses and eating them more than once a week (4.5%, 95% CI 0.3 to 8.8, p = 0.035), having cereals or grains for breakfast (5.4%, 95% CI 0.4 to 10.5, p = 0.035), and regularly consuming nuts (5.2%, 95% CI 0.2 to 10.2, p = 0.041). Additionally, increases in self-efficacy was associated with a 5.0% lower probability of skipping breakfast (95% CI -8.8 to -1.1, p = 0.012). Conclusions: Our results revealed a significant association between self-efficacy and MedDiet adherence among girls, whereas the relationship between self-efficacy and the MedDiet in boys was not significant. These results suggest that interventions aimed at improving adolescent dietary patterns should consider incorporating strategies to increase self-efficacy, potentially with sex-specific approaches.

Message framing materials applied to healthy eating decision-making for pregnant women with gestational diabetes mellitus: An exploratory study

AIMS

To develop and initially validate message framing materials for promoting healthy dietary decisions in GDM populations.

METHODS

The Delphi survey involved 17 experts, and consensus was obtained after two rounds. In Pre-survey I, 30 participants randomly selected one material (gain framing vs. loss framing) and complete a manipulation check item to ensure that the stimulus material manipulation was valid. Pre-survey II involved 60 participants who rated all messages using a Likert 5 rating questionnaire, a Wilcoxon signed rank sum test was used to examine the message framing effects.

RESULTS

After two rounds of Delphi surveys, experts reached consensus on the final materials, which contained two message framings, each containing 11 entries. The manipulation test for materials achieved 100% validity. The findings indicated significant message framing effects on healthy eating decisions among GDM populations, with loss-framed messages proving more persuasive.

CONCLUSION

Scientifically valid message framing materials were developed and initially applied, providing an empirical basis and direction for future related research.

Legumes or Meat? The Effectiveness of Recommendation Messages towards a Plant-Based Diet Depends on People's Identification with Flexitarians

In the present research, we analyzed how to promote a plant-based diet by involving 428 volunteers in a 2-week mobile app intervention. We compared messages promoting the addition of legumes versus messages promoting the replacement of meat with legumes. Messages were either combined or not combined with dynamic norms (i.e., information that more and more people are enacting the behavior). We compared these messages with a control condition (i.e., no message intervention) and we also analyzed the moderation effect of receivers' identification with flexitarians (i.e., people who occasionally eat animal products) and attitudes towards them. In the short term, addition messages increased legume consumption more than replacement messages, especially in people with a negative evaluation of flexitarians and low identification with them. In the long term, increased legume consumption was recorded only when addition messages were combined with dynamic norms. As for meat consumption, the replacement messages were more effective in reducing it in the short term than in the long term, especially in people with positive attitudes towards flexitarians. However, replacement messages combined with dynamic norms were more effective in the long term than in the short term. These results advance our comprehension of how to tailor dietary messages.

Affective components in promoting physical activity: A randomized controlled trial of message framing

Although the study of the affective components involved in predicting physical activity is spreading faster and faster, there is a lack of studies testing their role when promoting physical activity through message interventions. In the present study, we considered these components by focusing on how anticipated affective reactions and emotional processing of the messages influence receivers’ affective attitude toward physical activity, concurrent behavior, and future intention. A sample of 250 participants was involved in an intervention relying on prefactual (i.e., “If … then…”) messages promoting physical activity. All messages were sent through a research app and were focused on the expected consequences of exercising (or not exercising). Four experimental conditions involving messages differing as to their outcome sensitivity framing (i.e., gain, non-loss, non-gain, and loss) were compared to a control condition. Results showed that reading gain and non-gain messages enhanced the positive affective attitude toward physical activity, compared to control. Enhanced affective attitude after the intervention increased, in turn, self-reported physical activity and future intention. Interestingly, gain messages were even more persuasive for people with a low level of positive anticipated affective reactions. Furthermore, their effectiveness was especially attributable to the elicitation of hope in receivers. Discussion focuses on the advantages of considering affective components and their implications when promoting physical activity.