HM International Blog

The study was the work of researchers based at the Department of Epidemiology and Public Health, University College London (UCL), UK and the Institut National de la Santé et de la Recherche Médicale (INSERM), University of Montpellier, France, and is published in the November issue of the The British Journal of Psychiatry which is available online.

In their background information the authors explained that much research on diet and depression tends to focus on individual nutrients so they thought they would look at links between overall dietary patterns and depression.

For the study they looked at data covering 3,486 participants of average age 57 years (nearly three quarters were men) who were part of the Whitehall II study.

The Whitehall II study was set up by co-author and UCL Professor Sir Michael Marmot to investigate links between disease and social class, psychosocial factors and life style. It began by looking at the health of working people, and is now also looking to answer questions about how previous and current circumstances affect health and quality of life in an ageing group of participants.

The data allowed the researchers to identify two dietary patters: a whole food diet and a processed food diet. The whole food diet comprised mainly fresh fruits and vegetables and fish, while the processed diet comprised mainly sweetened desserts, fried foods, high fat dairy foods, processed meat and refined grains.

To assess depression, the researchers used self-reported data that had been gathered five years after the dietary data using the CES-D scale.

CES-D, short for Center for Epidemiologic Studies – Depression scale, is a commonly used self-report questionnaire for assessing depression. It asks a series of multiple choice questions about how the participant has been feeling over the past week, covering topics such as concentration, loss of appetite, worry, how well they have been able to shake off depressive moods, quality of sleep, feelings of loneliness, self-worth, energy levels, and so on.