The joint association of ultra-processed food consumption and mediterranean diet on chronic disease incidence among individuals with and without obesity

• Grant number: 25/14113-9
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• Start date: February 18, 2026
• End date: August 15, 2026
• Field of knowledge: Health Sciences - Collective Health - Epidemiology
• Principal Investigator: Maria Laura da Costa Louzada
• Grantee: Evelyn Oliveira da Silva Frade
• Supervisor: Marialaura Bonaccio
• Host Institution: Faculdade de Saúde Pública (FSP). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Institution abroad: Irccs Istituto Neurologico Mediterraneo Neuromed, Italy
• Associated to the scholarship: 23/11159-2 - Food processing and cardiometabolic risk in overweight and obese adults: a prospective study in the NutriNet-Brazil cohort, BP.DR

Abstract

Non-communicable chronic diseases are a major global public health challenge, accounting for approximately 60% of total disability-adjusted life years worldwide. In Italy, chronic diseases, particularly cardiovascular diseases, also are among the leading causes of mortality. Consistent evidence shows that the traditional Mediterranean diet, rich in fruits, vegetables, and whole grains, is associated with reduced chronic disease risk and mortality. More recent research also highlights the role of ultra-processed foods in increasing the risk of non-communicable chronic diseases. Obesity stands out among NCDs due to its global burden and its role as a major risk factor for chronic diseases; however, healthcare guidelines primarily emphasize weight loss over the importance of a healthy diet. Given this, the combined effects of ultra-processed foods and adherence to Mediterranean diet on chronic diseases remain underexplored among people with obesity. This study aims to investigate the joint effect of ultra-processed consumption and Mediterranean diet adherence on cardiovascular diseases, and cancer incidence stratified by obesity status. The study will allow for the investigation of whether high adherence to the Mediterranean diet moderates or attenuates the risks associated with high ultra-processed food consumption - or vice versa - or whether their effects on chronic disease incidence are independent or interactive. To answer these questions, we will use data from the Moli-sani cohort. Dietary intake will be assessed by a validated Food Frequency Questionnaire, with ultra-processed foods identified using the Nova system and Mediterranean diet adherence measured by the Mediterranean Diet Score. Data on the incidence of cardiovascular disease and cancer will be obtained through linkage with hospital discharge records and validated by review of medical records. The analyses will be stratified by obesity status at baseline. First, we will examine the independent associations of ultra-processed food consumption and Mediterranean diet adherence using Cox proportional hazards models: (1) crude model; (2) adjusted for sociodemographic, lifestyle, and clinical covariates, and (3) mutually adjusted for both dietary exposures. Next, to test additive and multiplicative interactions, Mediterranean diet and ultra-processed food intake will be dichotomized (high/low) by sex-specific medians and combined into four-level exposure variable. These results will provide insights into the synergy of ultra-processed food consumption and Mediterranean diet adherence on chronic disease incidence among people with obesity, providing evidence for targeted public health interventions.