The Association between Vegan, Vegetarian, and Omnivore Diet Quality and Depressive Symptoms in Adults: A Cross-Sectional Study

Abstract

Dietary patterns and depressive symptoms are associated in cross-sectional and prospective-designed research. However, limited research has considered depression risk related to meat-based and plant-based dietary patterns. This study explores the association between diet quality and depressive symptoms across omnivore, vegan, and vegetarian dietary patterns. A cross-sectional online survey utilised the Dietary Screening Tool (DST) and the Centre for Epidemiological Studies of Depression Scale (CESD-20) to measure diet quality and depressive symptoms, respectively. A total of 496 participants identified as either omnivores (n = 129), vegetarians (n = 151), or vegans (n = 216). ANOVA with Bonferroni post hoc corrections indicates that dietary quality was significantly different between groups F(2, 493) = 23.61, p < 0.001 for omnivores and vegetarians and omnivores and vegans. Diet quality was highest in the vegan sample, followed by vegetarian and omnivore patterns. The results show a significant, moderately negative relationship between higher diet quality and lower depressive symptoms (r = −0.385, p < 0.001) across groups. Hierarchical regression showed that diet quality accounted for 13% of the variability in depressive symptoms for the omnivore sample, 6% for vegetarians, and 8% for vegans. This study suggests that diet quality in a meat-based or plant-based diet could be a modifiable lifestyle factor with the potential to reduce the risk of depressive symptoms. The study indicates a greater protective role of a high-quality plant-based diet and lower depressive symptoms. Further intervention research is needed to understand the bi-directional relationship between diet quality and depressive symptoms across dietary patterns.

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

“…Some biological factors include decreased monoamine function, dysfunctional hypothalamic pituitary adrenal (HPA) axis, neuro‐progression/brain plasticity, mitochondrial disturbances (Lopresti et al, 2013; Pereira et al, 2020), cytokine‐mediated inflammatory processes, increased oxidative stress, immune responses (Berk et al, 2013), immuno‐inflammation, gut dysbiosis and gut/brain relationship (Kaplan et al, 2015; Pereira et al, 2020). While these biological factors play a role in the experience of depressive symptoms, they are also influenced by a diet rich in plant‐based foods such as fruit and vegetables (Bayes et al, 2021; Daneshzad et al, 2020; Nguyen et al, 2017; Walsh et al, 2023).…”

Depression, Anxiety, Emotional Eating, and Body Mass Index among Self-Reported Vegetarians and Non-Vegetarians: A Cross-Sectional Study in Peruvian Adults

“…For example, one study reported very low levels of omega-3 polyunsaturated fatty acids in vegetarians and vegans [ 56 ]. This reduction in omega-3 polyunsaturated fatty acid intake among some vegetarians may be due, in part, to the fact that the primary bioavailable source of these fatty acids is oily fish [ 57 ]. Deficiencies in these fatty acids could have a negative impact on mental health, brain function, and the modulation of neurotransmitters responsible for mood; this, in turn, could lead to anxiety [ 58 ].…”

Cohort profile: rationale and design of the Resource Center for Health Science (RECHS) project – a study of health hazards and medical cost burden among the Japanese population

“…13 The causes of non-communicable diseases and mental disorders involve a complex interplay between predisposing risk factors and various lifestyle, environmental and health-related exposures. [14][15][16] Moreover, a significant inter-relationship exists between non-communicable diseases and mental disorders. Therefore, to gain novel insights into the causes and consequences of noncommunicable diseases and mental disorders, large prospective studies that comprehensively collect diverse exposures prior to the onset of diseases are essential.…”

“…The causes of non-communicable diseases and mental disorders involve a complex interplay between predisposing risk factors and various lifestyle, environmental and health-related exposures 14–16. Moreover, a significant inter-relationship exists between non-communicable diseases and mental disorders.…”