A longitudinal analysis of Australian women's fruit and vegetable consumption and depressive symptoms

Abstract

Background: In Australia, women report higher rates of depressive symptoms than men. Research suggests that dietary patterns rich in fresh fruit and vegetables could protect against depressive symptoms. The Australian Dietary Guidelines suggest that consuming two servings of fruit and five serves of vegetables per day is optimal for overall health. However, this consumption level is often difficult for those experiencing depressive symptoms to achieve.

Aims: This study aims to compare diet quality and depressive symptoms in Australian women over time using (I) two serves of fruit and five serves of vegetables per day (FV7), and (ii) two serves of fruit and three serves of vegetables per day (FV5).

Materials and methods: A secondary analysis was conducted using data from the Australian Longitudinal Study on Women's Health over 12 years at three time points 2006 (n = 9145, Mean age = 30.6, SD = 1.5), 2015 (n = 7186, Mean age = 39.7, SD = 1.5), and 2018 (n = 7121, Mean age = 42.4, SD = 1.5).

Results: A linear mixed effects model found, after adjusting for covarying factors, a small significant inverse association between both FV7 (b = -.54, 95% CI = -.78, -.29) and FV5 (b = -.38, 95% CI = -.50, -.26) in depressive symptoms.

Discussion: These findings suggest an association between fruit and vegetable consumption and decreased depressive symptoms. The small effect sizes indicate caution should be taken in interpreting these results. The findings also suggest that current Australian Dietary Guideline recommendations need not be prescriptive to two fruit and five vegetables for impact on depressive symptoms.

Conclusions: Future research could evaluate reduced vegetable consumption (three serves per day) in identifying the protective threshold for depressive symptoms.

Keywords: ALSWH; depression; depressive symptoms; diet quality; dietary patterns.