Changes in dietary patterns and physical activity levels associated with the onset of depressive disorders

• Grant number: 25/14314-4
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: September 01, 2025
• End date: August 31, 2026
• Field of knowledge: Health Sciences - Collective Health - Epidemiology
• Principal Investigator: André de Oliveira Werneck
• Grantee: Damilly Maria dos Santos Muniz
• Host Institution: Faculdade de Saúde Pública (FSP). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Introduction: Depressive disorders have a considerable prevalence worldwide, leading to the reduction in quality of life and premature mortality. There is evidence showing that both the adoption of healthy dietary patterns and higher physical activity practice are associated with the prevention of depressive disorders, as well as people with depressive disorders present lower physical activity levels and unhealthier dietary patterns. However, how the development of depressive disorders affects the trajectory of health behaviours still warrants further investigation, especially to evaluate immediate changes following the incidence of depressive disorders. Objective: The objective of this project is to investigate changes in dietary pattern and physical activity levels related to the diagnosis of depression or the incidence of moderate to severe depressive symptoms. Methods: This project will use data from the NutriNet Brazil Study, which is a cohort study including adults living in Brazil. Currently, the NutriNet Brazil cohort has more than 113,000 participants and approximately 5 years of follow-up. Participants who developed depressive disorders during follow-up, at months 26, 32, 38, 44 and 50 will be included. Participants were evaluated using validated questionnaires and self-report of medical diagnosis, both reported by participants, with a periodicity of six months. Food consumption is assessed using 24-hour food recalls answered every three months and the practice of physical activity is reported every 24 months. Social determinants including gender, age, ethnicity, and education will be considered potential moderators. Confounding factors will be identified by building Directed Acyclic Graphs. The main analyses will include mixed linear models, including a time x phase (i.e., before or after the incidence of depression or moderate to severe depressive symptoms) interaction.