Effect of a Brazilian diet-based digital health intervention on preventing weight gain and depressive symptoms: The PREDIBRA Clinical Trial

• Grant number: 24/17553-7
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: March 01, 2025
• End date: February 28, 2029
• Field of knowledge: Health Sciences - Nutrition - Nutritional Analysis of Population
• Principal Investigator: Maria Laura da Costa Louzada
• Grantee: Laura Virgili Claro
• Host Institution: Faculdade de Saúde Pública (FSP). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 22/05636-0 - Program of population studies on the consumption of ultraprocessed foods and health, AP.TEM

Abstract

Introduction: The Dietary Guidelines for the Brazilian Population recommend that natural or minimally processed foods form the basis of the diet, while ultra-processed foods should be avoided. A dietary pattern that adheres to these recommendations has been associated with a lower risk of several health issues, such as obesity, cardiovascular disease, depression, and premature death in adults. Objective: To evaluate the effect of increased adherence to the Brazilian diet, as recommended by the Dietary Guidelines for the Brazilian Population, on weight change and reduction of depressive symptoms through a digital intervention. Methods: A randomized clinical trial will be conducted with a subsample of the NutriNet Brasil cohort, targeting individuals with high consumption of ultra-processed foods and overweight. The intervention will be implemented via an application designed to promote the Brazilian diet and nutritional teleconsultations, lasting for six months. Participants will be randomly assigned to one of four groups: two intervention groups (one receiving the application and teleconsultations, and another receiving only the application) and two control groups (one receiving incentive messages to stay in the study, and another with no intervention). Weight change and depressive symptoms will be the primary outcomes. Analysis will include comparisons of pre- and post-intervention outcomes, both within and between groups, using intention-to-treat methodology and appropriate statistical tests (Student's t-test, chi-square test, or ANOVA).