Mediterranean diet and depressive symptoms among older adults over time

To examine whether adherence to a Mediterranean-based dietary pattern is predictive of depressive symptoms among older adults.

Generalized estimating equation models were used to test the association between a Mediterranean-based dietary pattern and depressive symptoms over time. Models were adjusted for age, sex, race, education, income, widowhood, antidepressant use, total calorie intake, body mass index, smoking, alcohol consumption, number of self-reported medical conditions, cognitive function, and physical disability.

Chicago, Illinois.

Community-dwelling participants (n=3502) of the Chicago Health and Aging Project aged 65+ years (59% African American) who had no evidence of depression at the baseline.

Adherence to a Mediterranean-based dietary pattern was assessed by the MedDietScore. Dietary evaluation was performed with a food frequency questionnaire at baseline and related to incident depression as measured by the presence of four or more depressive symptoms from the 10-item version of the Center for Epidemiologic Studies Depression scale.

Over an average follow-up of 7.2 years, greater adherence to a Mediterranean-based diet was associated with a reduced number of newly occurring depressive symptoms (parameter estimate = -0.002, standard error = 0.001; p = 0.04). The annual rate of developing depressive symptoms was 98.6% lower among persons in the highest tertile of a Mediterranean-based dietary pattern compared with persons in the lowest tertile group.

Our results support the hypothesis that adherence to a diet comprised of vegetables, fruits, whole grains, fish, and legumes may protect against the development of depressive symptoms in older age.