Prevention of depression through nutritional strategies in high-risk persons: rationale and design of the MooDFOOD prevention trial

Background: Obesity and depression are two prevalent conditions that are costly to individuals and society. The bidirectional association of obesity with depression, in which unhealthy dietary patterns may play an important role, has been well established. Few experimental studies have been conducted to investigate whether supplementing specific nutrients or improving diet and food-related behaviors can prevent depression in overweight persons. Method/Design: The MooDFOOD prevention trial examines the feasibility and effectiveness of two different nutritional strategies [multi-nutrient supplementation and food-related behavioral change therapy (FBC)] to prevent depression in individuals who are overweight and have elevated depressive symptoms but who are not currently or in the last 6 months meeting criteria for an episode of major depressive disorder (MDD). The randomized controlled prevention trial has a two-by-two factorial design: participants are randomized to daily multi-nutrient supplement (omega-3 fatty acids, calcium, selenium, B-11 vitamin and D-3 vitamin) versus placebo, and/or FBC therapy sessions versus usual care. Interventions last 12 months. In total 1000 participants aged 18-75 years with body mass index between 25-40 kg/m(2) and with a Patient Health Questionnaire-9 score >= 5 will be recruited at four study sites in four European countries. Baseline and follow-up assessments take place at 0, 3, 6, and 12 months. Primary endpoint is the onset of an episode of MDD, assessed according to DSM-IV based criteria using the MINI 5. 0 interview. Depressive symptoms, anxiety, food and eating behavior, physical activity and health related quality of life are secondary outcomes. During the intervention, compliance, adverse events and potentially mediating variables are carefully monitored. Discussion: The trial aims to provide a better understanding of the causal role of specific nutrients, overall diet, and food-related behavior change with respect to the incidence of MDD episodes. This knowledge will be used to develop and disseminate innovative evidence-based, feasible, and effective nutritional public health strategies for the prevention of clinical depression.
Funding for this paper was provided by the European Union FP7 MooDFOOD Project 'Multi-country cOllaborative project on the rOle of Diet, FOod-related behaviour, and Obesity in the prevention of Depression' (grant agreement no. 613598). This work is supported in the UK by the National Institute for Health Research (NIHR), through the Primary Care Research Network, and the NIHR Exeter Clinical Research Facility. Funding sponsors did not participate in the study design; collection, management, analysis, and interpretation of data; or writing of the report. They did not participated in the decision to submit the report for publication, nor had ultimate authority over any of these activities.