The objective of this interventional study is to pilot test a newly evidence-based intervention integrating different dimensions of eating pleasure to promote the consumption of fruits et vegetables. The target population for this study is men and women, aged 18-65 years old, living with a higher weight.The main hypothesis is that this newly pleasure-oriented intervention is feasible and acceptable for the target population. Participants will be randomized in two groups, a first group receiving the newly, 12-week pleasure-oriented intervention (intervention group) and a second group receiving no intervention (control group).

Participants will:

• Complete a battery of online questionnaires at home before and after the 12-week nutritional intervention (both intervention and control groups);
• For participants assigned to the intervention group only: take part in a 12-week nutritional intervention consisting of 10 group sessions held at Laval University (approximately 2 hours each) and an individual follow-up by phone (30 to 45 minutes). After each session, participants will complete a short questionnaire assessing their appreciation of the session (5 to 10 minutes), as well as a comprehensive appreciation questionnaire at the end of the 12-week intervention (25 to 30 minutes).

Research Problem and Hypothesis The health impact of several nutrients, foods, and certain dietary patterns is well documented. Despite this knowledge, food choices within the population remain suboptimal. Furthermore, attempting to promote healthy eating by focusing on the nutritional quality of foods can present certain pitfalls. Indeed, some studies have suggested that there is a persistent perception across different populations-particularly among individuals with higher body weight - that foods considered "healthy" are necessarily less tasty than "unhealthy" foods. This perception may undermine efforts to adhere to healthy eating, given the importance of taste and the pleasure of eating in everyday food choices. In this context, an approach that leverages the pleasure of eating as a driver for healthy eating could be highly relevant. Interestingly, there is growing evidence that eating pleasure can be used to promote healthy eating. Nevertheless, no systematically developed, evidence-based intervention integrating eating pleasure to encourage healthier food choices has yet been described in the literature. To address this gap, the investigators designed an intervention aimed at increasing fruit and vegetable consumption among adults with higher body weight by incorporating eating pleasure into intervention strategies. The research team is now at the stage of assessing its feasibility and acceptability. The choice of this target population (i.e., adults with higher body weight) is based on the fact that these individuals are more likely to seek nutritional advice and benefit from improvements in their dietary intake and behaviors. The main hypothesis is that the proposed intervention will be considered feasible and acceptable by this population.

Objectives and Methodological Approach This intervention was developed using Intervention Mapping, a widely used protocol in behavioral science for designing effective, theory-based, evidence-informed interventions that place the needs and perspectives of the target population at the center of the development process.

In accordance with the Intervention Mapping protocol, four specific objectives were formulated:

1. Assess how the target population adheres to the different dimensions of eating pleasure;
2. Explore dietitians' perspectives on the elements to consider to maximize the relevance, feasibility, and applicability of using eating pleasure to promote healthy eating by conducting in-depth interviews exploring how the different dimensions of eating pleasure are used to encourage healthy eating, the challenges , and the themes and activities that should be integrated into the intervention;
3. Develop the intervention in terms of performance and change objectives, theory-based methods and strategies, and intervention components;
4. Conduct a pilot study of the intervention to assess its feasibility and acceptability. To do so, five indicators of feasibility and acceptability will be evaluated: (1) attrition rate, (2) adherence rate, (3) participation rate, (4) perceived acceptability, and (5) implementation fidelity. Performance and change objectives targeted by the intervention will also be measured to identify effective components and those requiring improvement. Measures related to eating pleasure will also be collected, as eating pleasure is considered a key driver of change in this intervention. Dietary quality will be assessed before and after the intervention, as it is the primary outcome of the planned full-scale randomized controlled trial. Finally, certain eating behaviors will also be measured before and after the intervention to ensure that improvements in dietary intake are accompanied by healthy eating behaviors. Similarly, attitudes and beliefs about weight will be assessed to evaluate the impact of the intervention on these variables.

The present application concerns specific objective 4. The intervention will last 12 weeks and include 10 group sessions as well as an individual follow-up.

Participants and Recruitment A total of 88 participants will be recruited and randomly assigned to one of two study groups: a control group (no intervention, n = 44) and an intervention group (n = 44). Allocation will ensure equitable gender representation, with an equal number of men and women in each group. Participants identifying as "other" gender will also be evenly distributed between the two groups. Half of the participants in each group will be aged 18-42 years, and the other half will be aged 43-65 years (42 years being the median age of the 18-65 population in Quebec).

Inclusion criteria are: (1) aged 18-65 years; (2) presenting with higher body weight, defined in this study as a body mass index (BMI) ≥ 30 kg/m²; (3) able to come to INAF (Laval University) if randomized to the intervention group; and (4) to be fluent in French, as the nutrition intervention will be conducted in this language. Participants without Internet access will be able to come to Laval University to complete their online questionnaires, reducing recruitment bias associated with socioeconomic status. Individuals currently suffering from or with a history of eating disorders (e.g., binge eating disorder, anorexia, or bulimia), as well as pregnant or breastfeeding, will be excluded from this study, as these conditions may significantly influence perceptions related to eating pleasure and healthy eating.

Participants will be recruited through mailing lists of the research institute (INAF) and Laval University (students and staff), as well as via social media (e.g., Facebook, Instagram), the INAF website, and certain community collaborators and affiliated centers of the co-investigators. Interested individuals will be invited to contact the research team and provide their phone number. A team member will then call them to present the study and ask a few questions to assess eligibility. Once eligibility is confirmed, the consent form will be presented via the secure FANI platform. If participants have questions, they will be invited to contact the research team. They will have as much time as needed to consider participation. Those wishing to take part in the study will be asked to indicate their consent in the online consent form.

Randomization Men and women from the two age subgroups described above will be evenly distributed between two groups: one group will receive the intervention, and the other will receive no intervention (control group). It has been suggested that, in pilot studies, a no-treatment control group may be preferable to avoid prematurely discarding a potentially promising intervention. The intervention will be facilitated by one or more dietitians involved in the steering committee responsible for developing the intervention. To minimize bias, the randomization sequence for participants will be generated by a computer algorithm using random numbers, taking into account participants' gender and age.

Steering Committee As recommended in the Intervention Mapping process, a steering committee was established at the beginning of the project to provide support, guidance, and oversight at key stages. This committee includes the researchers and the student involved in the project, three dietitians working with the target population, and two individuals from the target population (one man and one woman).

Statistical Analyses Quantitative data related to feasibility and acceptability measures will be presented as means and percentages. For qualitative data, an inductive thematic content analysis will be conducted independently by two team members using NVivo software. Sociodemographic data (e.g., age, gender, income, education level, ethnicity or cultural background) will be entered as attributes to determine whether they influence expressed feedback.

Changes in dependent variables (HEFI-2019, HEFI-FV, IES-3 and DEBQ scales, performance objectives, eating pleasure scales, FAAT) will be compared between intervention and control groups using the PROC MIXED procedure for repeated measures in SAS software (Cary, NC). Confounding variables (e.g., age, gender, income, education level, ethnicity/cultural background, obesity-related comorbidities) and their interactions with the intervention effect will be tested and included as covariates in the models.

Contribution to Knowledge Advancement This study will make a significant contribution to advancing knowledge in healthy eating promotion by leveraging eating pleasure as an innovative driver. The surveys with individuals with higher body weight and dietitians revealed new ways in which eating pleasure can be used to support healthy eating. This intervention will then systematically determine the best way to integrate these findings and other available evidence into practice by health professionals. This project will also provide a new example of collaboration between researchers, clinicians, and the public in generating knowledge that can be rapidly applied.

Perspectives and Knowledge Mobilization Plan This project will help better understand how to use eating pleasure to promote healthy eating among individuals with higher body weight. It will be followed by a randomized controlled trial to evaluate the intervention's effectiveness. Ultimately, an online training workshop for dietitians could be developed to ensure dissemination and sustainability of the intervention, with complementary research to monitor implementation.

Given the significant intercultural differences in food perceptions, the intervention will need to be adapted if researchers or health professionals wish to use it in populations outside Quebec. To this end, a detailed report on the intervention's development on the Open Science Framework platform will be published, and the intervention manual will be available upon request. Thanks to this methodology used in this study, the intervention can be appropriately adapted using effective strategies.

Finally, new knowledge generated by this project will be disseminated through peer-reviewed scientific publications and conference presentations. As a member of the advisory committee established by Health Canada for developing a tool to measure adherence to Canada's Food Guide recommendations, Dr. Lemieux will use the results of this research to contribute to defining the measurement of the recommendation "Enjoy your food" and, eventually, to developing strategies to promote adherence.

Inclusion Criteria:

• Aged 18 to 65 years
• Presenting with higher body weight, defined in this study as a body mass index (BMI) ≥ 30 kg/m²
• Fluent in French, as the nutritional intervention is conducted in this language
• Able to travel to Laval University to take part in the nutritional intervention

Exclusion Criteria:

• Current or past diagnosis of an eating disorder (e.g., binge eating disorder, anorexia nervosa, or bulimia nervosa)
• Pregnant or breastfeeding individuals

The data underlying the findings are not publicly available because the original approval by the Research Ethics Committee of Laval University and the informed consent from the subjects participating in the studies did not include such a direct, free access. Data can be requested from the principal investigator at simone.lemieux@fsaa.ulaval.ca for researchers who meet the criteria for access to confidential data.