Higher Adherence to the Australian Dietary Guidelines Is Associated with Better Mental Health Status among Australian Adult First-Time Mothers.

BACKGROUND: Mental health disorders are a leading cause of disability worldwide, including in first-time mothers. Understanding the associations between diet and depressive symptoms could assist in improving mental health status in this group.

OBJECTIVE: Our aim was to determine the association between diet quality, fruit, vegetable, and fish consumption and depressive symptoms in first-time mothers aged 19 to 45 years.

DESIGN: We analyzed cross-sectional, baseline data (3 months postpartum) from the Melbourne InFANT (Infant Feeding, Activity, and Nutrition Trial) Extend Program.

PARTICIPANTS/SETTING: Participants were first-time Australian mothers aged 19 to 45 years from the Geelong and Melbourne regions of Victoria, Australia (n=457).

MAIN OUTCOME MEASURES: A self-administered, 137-item food frequency questionnaire assessed dietary intake over the past year. Adherence to the 2013 Australian Dietary Guidelines was assessed using the Dietary Guideline Index as a measure of diet quality. Depressive symptoms were determined using the Center for Epidemiologic Studies Depression Scale.

STATISTICAL ANALYSIS PERFORMED: Relationships between diet quality, fruit, vegetable, and fish intake and depressive symptoms were investigated using linear regression adjusted for relevant covariates (age, smoking status, sleep quality, education, physical activity status, and body mass index).

RESULTS: Better diet quality, as indicated by a higher score on the Dietary Guideline Index, was associated with lower depressive symptoms after adjusting for relevant covariates (β=-.034; 95% CI -.056 to -0.012). There were no other associations between dietary intake and depressive symptoms.

CONCLUSIONS: Adherence to the Australian Dietary Guidelines was associated with better mental health status among first-time mothers. Further research, including longitudinal and intervention studies, are required to determine causality between dietary intake and depressive symptoms, which might help inform future public health nutrition programs for this target group.