Dietary linoleic and oleic fatty acids in relation to severe depressed mood: 10 years follow-up of a national cohort

Fatty acid intake and prevalence of depression among Brazilian graduates and postgraduates (CUME Study)

BACKGROUND

Dietary fatty acids are related to the development of several inflammatory-related diseases, which may include depression. So, the association between fatty acids, culinary oils and fat intake and depression in highly educated Brazilians was evaluated.

METHODS

Multicenter cross-sectional study using baseline data from the Cohort of Universities of Minas Gerais. The diagnosis of depression was self-reported, and the daily intake of fatty acids was assessed using a 144-item food frequency questionnaire (FFQ).

RESULTS

A total of 7157 participants (68.83 % women) with a median age of 33 years were included. The prevalence of depression was 12.60 % (N = 902). In the adjusted analyses, it was observed that individuals with the highest intake of omega-6 fatty acids (n-6) (OR: 1.36, 95 % CI 1.11-1.67) had a higher prevalence of depression. This increased n-6 intake was identified as a risk factor for depression only among male participants, while among overweight participants, higher n-6 intake was also positively associated with depression. Conversely, a higher ratio of polyunsaturated to monounsaturated and saturated fatty acids (PM/S) was also found to be positively associated with depression, but this association was observed only among non-overweight participants. No associations were found between the consumption of culinary oils or fats and depression.

LIMITATIONS

Cross-sectional design limits the assessment of causality. The use of the FFQ can make estimates more difficult.

CONCLUSION

Higher consumption of n-6, and higher PM/S ratios were associated with depression, and individual factors can interfere. The mental health care policies should include specific nutritional strategies.

Metabolome-associated psychological comorbidities improvement in irritable bowel syndrome patients receiving a probiotic

Our recent randomized, placebo-controlled study in Irritable Bowel Syndrome (IBS) patients with diarrhea or alternating bowel habits showed that the probiotic Bifidobacterium longum (BL) NCC3001 improves depression scores and decreases brain emotional reactivity. However, the involved metabolic pathways remain unclear. This analysis aimed to investigate the biochemical pathways underlying the beneficial effects of BL NCC3001 using metabolomic profiling. Patients received probiotic (1x 1010CFU, n=16) or placebo (n=19) daily for 6 weeks. Anxiety and depression were measured using the Hospital Anxiety and Depression Scale. Brain activity in response to negative emotional stimuli was assessed by functional Magnetic Resonance Imaging. Probiotic fecal abundance was quantified by qPCR. Quantitative measurement of specific panels of plasma host-microbial metabolites was performed by mass spectrometry-based metabolomics. Probiotic abundance in feces was associated with improvements in anxiety and depression scores, and a decrease in amygdala activation. The probiotic treatment increased the levels of butyric acid, tryptophan, N-acetyl tryptophan, glycine-conjugated bile acids, and free fatty acids. Butyric acid concentration correlated with lower anxiety and depression scores, and decreased amygdala activation. Furthermore, butyric acid concentration correlated with the probiotic abundance in feces. In patients with non-constipation IBS, improvements in psychological comorbidities and brain emotional reactivity were associated with an increased abundance of BL NCC3001 in feces and specific plasma metabolites, mainly butyric acid. These findings suggest the importance of a probiotic to thrive in the gut and highlight butyric acid as a potential biochemical marker linking microbial metabolism with beneficial effects on the gut-brain axis.

rTMS ameliorates depressive-like behaviors and regulates the gut microbiome and medium- and long-chain fatty acids in mice exposed to chronic unpredictable mild stress

INTRODUCTION

Repetitive transcranial magnetic stimulation (rTMS) is a clinically useful therapy for depression. However, the effects of rTMS on the metabolism of fatty acids (FAs) and the composition of gut microbiota in depression are not well established.

METHODS

Mice received rTMS (15 Hz, 1.26 T) for seven consecutive days after exposure to chronic unpredictable mild stress (CUMS). The subsequent depressive-like behaviors, the composition of gut microbiota of stool samples, as well as medium- and long-chain fatty acids (MLCFAs) in the plasma, prefrontal cortex (PFC), and hippocampus (HPC) were evaluated.

RESULTS

CUMS induced remarkable changes in gut microbiotas and fatty acids, specifically in community diversity of gut microbiotas and PUFAs in the brain. 15 Hz rTMS treatment alleviates depressive-like behaviors and partially normalized CUMS induced alterations of microbiotas and MLCFAs, especially the abundance of Cyanobacteria, Actinobacteriota, and levels of polyunsaturated fatty acids (PUFAs) in the hippocampus and PFC.

CONCLUSION

These findings revealed that the modulation of gut microbiotas and PUFAs metabolism might partly contribute to the antidepressant effect of rTMS.

Krill oil treatment ameliorates lipid metabolism imbalance in chronic unpredicted mild stress-induced depression-like behavior in mice

The pathology of depression involves various factors including the interaction between genes and the environment. The deficiency of n-3 polyunsaturated fatty acids (n-3 PUFAs) in the brain and depressive symptoms are closely related. Krill oil contains abundant amounts of n-3 PUFAs incorporated in phosphatidylcholine. However, the effect of krill oil treatment on depression-like behaviors induced by chronic stress and its molecular mechanism in the brain remain poorly understood. Here, we used a chronic unpredictable mild stress (CUMS) model to evaluate the effect of krill oil on depression-like behaviors and explored its molecular mechanism through lipid metabolomics and mRNA profiles in the whole brain. We observed that CUMS-induced depression-like behaviors were ameliorated by krill oil supplementation in mice. The metabolism of glycerophospholipids and sphingolipids was disrupted by CUMS treatment, which were ameliorated after krill oil supplementation. Further analysis found that differently expressed genes after krill oil supplementation were mainly enriched in the membrane structures and neuroactive ligand-receptor interaction pathway, which may be responsible for the amelioration of CUMS-induced depression-like behaviors. Altogether, our results uncovered the relationship between lipid metabolism and CUMS, and provided new strategies for the prevention and treatment of depression.

Plant-based dietary patterns and their association with mood in healthy individuals

Background: Healthy, plant-based dietary patterns, particularly the Mediterranean diet (MD), have been associated with positive effect on mood symptoms and have been proposed to help prevent age-related cognitive decline. However, to date no study has investigated which existing plant-based dietary pattern might be most likely to be associated with better mood in the general population. The aim of this study was to evaluate the relationship between different plant-rich dietary patterns and current mood in healthy individuals across a broad age range. Methods: We evaluated 333 healthy participants aged 8-79, who previously participated in dietary intervention studies. Current mood was assessed with the Positive and Negative Affect Schedule (PANAS) questionnaire, standardised by Z scores. Dietary patterns were estimated using food consumption data obtained from the European Prospective Investigation into Cancer (EPIC) Food Frequency Questionnaires (FFQ), and included the Plant-based Diet Index (PDI), Dietary Approaches to Stop Hypertension Diet (DASH), Mediterranean-DASH Diet Intervention for Neurodegenerative Delay (MIND), Original Mediterranean Diet (oMED) and Alternate Mediterranean Diet (aMED). Results: PDI, DASH, oMED and aMED diet scores were all significantly associated with positive mood (rs = 0.12-0.16), but not with negative mood. Linear regression models suggested that after adjusting for potential confounders (sex and age), only the oMED and aMED diet scores were still significantly associated with positive mood (β = 0.119, p = 0.031 and β = 0.111, p = 0.048, respectively). Furthermore, the relationship between PDI diet scores and positive mood was only significant in children (β = 0.663, p = 0.003), pointing to a potential moderating effect of age in the relationship between PDI and positive mood. Conclusion: Adherence to oMED and aMED diets is associated with better mood in healthy adults, while the PDI diet might be more specifically associated with positive mood in children.

A Preliminary Comparison of Plasma Tryptophan Metabolites and Medium- and Long-Chain Fatty Acids in Adult Patients with Major Depressive Disorder and Schizophrenia

Background and Objectives: Disturbance of tryptophan (Trp) and fatty acid (FA) metabolism plays a role in the pathogenesis of psychiatric disorders. However, quantitative analysis and comparison of plasma Trp metabolites and medium- and long-chain fatty acids (MCFAs and LCFAs) in adult patients with major depressive disorder (MDD) and schizophrenia (SCH) are limited. Materials and Methods: Clinical symptoms were assessed and the level of Trp metabolites and MCFAs and LCFAs for plasma samples from patients with MDD (n = 24) or SCH (n = 22) and healthy controls (HC, n = 23) were obtained and analyzed. Results: We observed changes in Trp metabolites and MCFAs and LCFAs with MDD and SCH and found that Trp and its metabolites, such as N-formyl-kynurenine (NKY), 5-hydroxyindole-3-acetic acid (5-HIAA), and indole, as well as omega-3 polyunsaturated fatty acids (N3) and the ratio of N3 to omega-6 polyunsaturated fatty acids (N3: N6), decreased in both MDD and SCH patients. Meanwhile, levels of saturated fatty acids (SFA) and monounsaturated fatty acids (MUFA) decreased in SCH patients, and there was a significant difference in the composition of MCFAs and LCFAs between MDD and SCH patients. Moreover, the top 10 differential molecules could distinguish the two groups of diseases from HC and each other with high reliability. Conclusions: This study provides a further understanding of dysfunctional Trp and FA metabolism in adult patients with SCH or MDD and might develop combinatorial classifiers to distinguish between these disorders.

Dietary Fats and Depressive Symptoms in Italian Adults

BACKGROUND

Depression represents one of the major causes of disability worldwide, with an important socioeconomic cost. Although many risk factors have been considered in its pathogenesis, nutrition seems to play a determinant role in its prevention. With regard to individual macronutrients, dietary fats and especially n-3 polyunsaturated fatty acids (n-3 PUFA) are the most studied. However, previous data about other dietary fatty acids, such as n-6 PUFA, are conflicting, and little is known about saturated fatty acids (SFA), especially when considering carbon chain length. Thus, we investigated whether single types and subtypes of dietary fats are related to depressive symptoms in Italian individuals living in the Mediterranean area.

METHODS

Dietary and socio-demographic data of 1572 individuals were analyzed. Food frequency questionnaires (FFQs) were used to determine the consumption of total dietary fat and each specific class of dietary fat, such as SFA, monounsaturated fatty acid (MUFA), and PUFA. The intake of fatty acids was also assessed according to the carbon-chain length of each single class. The Center for Epidemiologic Studies Depression Scale (CES-D) was used as a screening tool for depressive symptoms.

RESULTS

After adjustment for potential confounding factors, a significant inverse association between low/moderate levels of PUFA intake and depressive symptoms (Q2 vs. Q1, odds ratio (OR) = 0.60, 95% CI: 0.44, 0.84) was found. On the other hand, moderate saturated fat consumption was associated with depressive symptoms (Q3 vs. Q1, OR = 1.44, 95% CI: 1.02, 2.04). However, when considering carbon chain length, individuals with a lower to moderate intake of short-chain saturated fatty acids (SCSFA) and medium-chain saturated fatty acids (MCSFA) were less likely to have depressive symptoms (Q3 vs. Q1, OR = 0.48, 95% CI: 0.31, 0.75), while moderate intake of arachidic acid (C20:0) was directly associated with depressive symptoms (Q3 vs. Q1, OR = 1.87, 95% CI: 1.26, 2.77). Among single MUFAs, higher myristoleic acid (C14:1) intake was directly associated with depressive symptoms (Q4 vs. Q1, OR = 1.71, 95% CI: 1.12, 2.61), while moderate intake of erucic acid (C22:1) was associated with lower odds of having depressive symptoms (Q3 vs. Q1, OR = 0.54, 95% CI: 0.33, 0.86). When considering individual PUFAs, individuals with moderate and higher intakes of arachidonic acid (C20:4) were less likely to have depressive symptoms (OR = 0.64, 95% CI: 0.45, 0.91; OR = 0.59, 95% CI: 0.38, 0.91, respectively). Similarly, higher eicosapentaenoic acid (C20:5) intake was inversely associated with depressive symptoms (Q4 vs. Q1, OR = 0.35, 95% CI: 0.12, 0.98), while a significant association for docosahexaenoic acid (C22:6) was retrieved only for low intakes (Q2 vs. Q1, OR = 0.33, 95% CI: 0.12, 0.88).

CONCLUSIONS

Dietary fat intake may be associated with depressive symptoms, underlying the importance of distinguishing between different fat types. This study confirms the pivotal role of PUFAs and reopens the debate on the role of saturated fatty acids, suggesting plausible effects of moderate intakes of short-chain fatty acids.

Association between meatless diet and depressive episodes: A cross-sectional analysis of baseline data from the longitudinal study of adult health (ELSA-Brasil)

BACKGROUND

The association between vegetarianism and depression is still unclear. We aimed to investigate the association between a meatless diet and the presence of depressive episodes among adults.

METHODS

A cross-sectional analysis was performed with baseline data from the ELSA-Brasil cohort, which included 14,216 Brazilians aged 35 to 74 years. A meatless diet was defined from in a validated food frequency questionnaire. The Clinical Interview Schedule-Revised (CIS-R) instrument was used to assess depressive episodes. The association between meatless diet and presence of depressive episodes was expressed as a prevalence ratio (PR), determined by Poisson regression adjusted for potentially confounding and/or mediating variables: sociodemographic parameters, smoking, alcohol intake, physical activity, several clinical variables, self-assessed health status, body mass index, micronutrient intake, protein, food processing level, daily energy intake, and changes in diet in the preceding 6 months.

RESULTS

We found a positive association between the prevalence of depressive episodes and a meatless diet. Meat non-consumers experienced approximately twice the frequency of depressive episodes of meat consumers, PRs ranging from 2.05 (95%CI 1.00-4.18) in the crude model to 2.37 (95%CI 1.24-4.51) in the fully adjusted model.

LIMITATIONS

The cross-sectional design precluded the investigation of causal relationships.

CONCLUSIONS

Depressive episodes are more prevalent in individuals who do not eat meat, independently of socioeconomic and lifestyle factors. Nutrient deficiencies do not explain this association. The nature of the association remains unclear, and longitudinal data are needed to clarify causal relationship.

Causal effects of fatty acids on depression: Mendelian randomization study

Objectives

Fatty acids (FA) are widely believed to play a role in the pathophysiology of depression. However, the causal relationships between FA and depression remain elusive and warrant further research. We aimed to investigate the potential causal relationship between FA [saturated fatty acids (SFA), mono-unsaturated fatty acids (MUFA), and polyunsaturated fatty acids (PUFA)] and the risk of depression using Mendelian randomization (MR) analysis.

Methods

We conducted a two-sample MR analysis using large-scale European-based genome-wide association studies (GWASs) summary data related to depression (n = 500,199 individuals) and FA [saturated fatty acids (SFA), mono-unsaturated fatty acids (MUFA), and polyunsaturated fatty acids (PUFA)] levels. MR analysis was performed using the Wald ratio and inverse variance-weighted (IVW) methods, and sensitivity analysis was conducted by the simple mode, weighted mode, weighted median method, and MR-Egger method.

Results

We found the causal effects for the levels of oleic acid (OA; OR = 1.07, p = 5.72 × 10^-4), adrenic acid (OR = 0.74, p = 1.01 × 10^-3), α-linolenic acid (ALA; OR = 2.52, p = 1.01 × 10^-3), eicosapentaenoic acid (EPA; OR = 0.84, p = 3.11 × 10^-3) on depression risk, after Bonferroni correction. The sensitivity analyses indicated similar trends. No causal effect between the levels of SFA and depression risk was observed.

Conclusion

Our study suggests that adrenic acid and EPA are protective against the risk of depression, while OA and ALA are potential risk factors for depression. Nonetheless, the underlying mechanisms that mediate the association between these FAs and depression risk should be investigated in further experiments.

Abnormal erythrocyte fatty acid composition in first-diagnosed, drug-naïve patients with depression

BACKGROUND & AIMS

The correlation between fatty acids (FAs) and depression is not yet conclusive. This study examined the relationship of FAs composition with the presence and clinical characteristics of first-diagnosed, drug-naïve patients with depression.

METHODS

A total of 139 first-diagnosed, drug-naïve patients with depression and 55 healthy controls (HCs) were included in the cross-sectional study. The levels of erythrocyte membrane FAs were compared and then the correlation between clinical symptoms and fatty acid levels in depression was investigated.

RESULTS

Compared to HCs, patients with depression had higher C18:1n9t (z = -2.033, p = 0.042), C20:4n6 (z = -2.104, p = 0.035), C20:3n6 (z = -2.104, p = 0.035) and n-6 polyunsaturated fatty acids (PUFAs) (z = -2.127, p = 0.033), whereas the levels of C18:1n9c (z = -3.348, p = 0.001) were significantly lower. Higher C20:3n6, C20:4n6, C18:1n9t and n-6 PUFAs levels were associated with higher severity of depressive and anxiety symptoms in patients with depression, and the correlation remained after adjusting for the related confounding factors (p < 0.05).

CONCLUSIONS

Patients with first-diagnosed, drug-naïve depression show abnormal erythrocyte fatty acid composition. Trans fatty acids (TFAs) and n-6 PUFAs levels are closely related to clinical characteristics of depression. This study indicated that increased n-6 PUFAs and TFAs are characteristic changes of first-diagnosed, drug-naïve depression.

The association of dietary macronutrient quality indices with depression and anxiety symptoms and quality of life in Iranian adults: The LipoKAP study

BACKGROUND

Macronutrients' quality may impact differently on mental health and quality of life (QOL). This study aimed to investigate the potential relationship between the carbohydrate quality index (CQI), fat quality index (FQI), protein quality index (PQI), the affective mental symptoms and QOL among Iranian adults.

METHODS

The LipoKAP is a cross-sectional study, conducted with 2456 adults in Iran. A validated food frequency questionnaire was used to evaluate usual dietary intakes. A validated Iranian version of the Hospital Anxiety and Depression Scale was used to assess the severity of anxiety and depression. QOL was assessed by EQ-5D.

RESULT

In the fully adjusted model, participants in the highest tertile of CQI had lower QOL than those in the lowest tertile (OR = 1.35; 95 % CI: 1.06, 1.73). Individuals in the top tertile of FQI (OR = 0.71; 95 % CI: 0.55, 0.91) and PQI (OR = 0.78; 95 % CI: 0.60; 1.01) were less likely to report lower QOL than those in the bottom tertile. An inverse association was found between PQI and depressive symptoms (OR = 0.72, 95 % CI: 0.55, 0.95), but not for CQI and FQI.

LIMITATIONS

The cross-sectional design of the study and the use of a memory-based dietary tool may limit the generalizability of our findings.

CONCLUSION

Higher PQI was associated with lower risk of depressive symptoms and having a low-quality life. Although CQI and FQI were not related to depressive and anxiety symptoms, higher values of FQI were associated with better QOL, while CQI showed an inverse association.

The Relationship Between Linoleic Acid Intake and Psychological Disorders in Adults

Background

The association between linoleic acid (LA) intake and mental disorders has not been extensively studied in Middle-Eastern populations. We investigated the association between LA intake and the prevalence of depression, anxiety, and psychological distress in a large group of Iranian adults.

Methods

This cross-sectional study was conducted on 3,362 middle-aged adults. LA intake was determined through a validated dish-based 106-item semiquantitative food frequency questionnaire (FFQ). The validated Hospital Anxiety and Depression Scale (HADS) and General Health Questionnaire (GHQ) were used to define psychological disorders.

Results

The prevalence of depression, anxiety, and psychological distress among the study population was 28.6, 13.6, and 22.6%, respectively. After adjustment for potential confounders, individuals in the top quartile of LA intake had 41% more likely to be depressed compared to those in the bottom quartile (OR = 1.41, 95% CI: 1.02–1.95). Stratified analysis by sex revealed that men in the fourth quartile of LA intake, compared to the first quartile, had 80% higher odds of depression, after considering all potential confounders (OR = 1.80, 95% CI: 1.01–3.19). More consumption of LA was also associated with higher odds of depression in older adults (OR = 2.45, 95% CI: 1.46–4.10) and normal-weight individuals (OR = 1.75, 95% CI: 1.13–2.72). Additionally, higher intake of LA was related to 90% higher odds of psychological distress in older participants (OR = 1.90, 95% CI: 1.08–3.36). No significant relation was found between LA intake and anxiety.

Conclusion

We found that higher intake of LA, as percentage of energy, was positively associated with depression, especially in men, older adults, and normal-weight subjects. Higher intake of LA was also related to higher odds of psychological distress in older individuals. More studies, particularly prospective cohorts, are needed to confirm these findings.

Chronic consumption of a high linoleic acid diet during pregnancy, lactation and post-weaning period increases depression-like behavior in male, but not female offspring

Polyunsaturated fatty acids (PUFAs) play an essential role in brain development. Emerging data have suggested a possible link between an imbalance in PUFAs and cognitive behavioral deficits in offspring. A diet rich in high linoleic acid (HLA), typically from preconception to lactation, leads to an increase in the ratio of omega-6 (n-6) to omega-3 (n-3) fatty acids in the fetus. Arising research has suggested that a deficiency in omega-3 fatty acids is a potential risk factor for inducing autism spectrum disorder (ASD)-like behavioral deficits. However, the impact of a high n- diet during preconception, pregnancy, lactation, and post-weaning on the brain development of adolescent offspring are yet to be determined. This study examined whether consumption of an HLA diet during pregnancy, lactation, and post-weaning induced social and cognitive impairments in female and male offspring rats that resemble autistic phenotypes in humans. Female Wistar Kyoto rats were fed with either HLA or low linoleic acid (LLA) control diet for 10 weeks before mating, then continued with the same diet throughout the pregnancy and lactation period. Female and male offspring at 5 weeks old were subjected to behavioral tests to assess social interaction behavior and depression-/anxiety-like behavior. Our result showed that chronic consumption of an HLA diet did not affect sociability and social recognition memory, but induced depression-like behavior in male but not in female offspring.

Depression phenotype identified by using single nucleotide exact amplicon sequence variants of the human gut microbiome

Single nucleotide exact amplicon sequence variants (ASV) of the human gut microbiome were used to evaluate if individuals with a depression phenotype (DEPR) could be identified from healthy reference subjects (NODEP). Microbial DNA in stool samples obtained from 40 subjects were characterized using high throughput microbiome sequence data processed via DADA2 error correction combined with PIME machine-learning de-noising and taxa binning/parsing of prevalent ASVs at the single nucleotide level of resolution. Application of ALDEx2 differential abundance analysis with assessed effect sizes and stringent PICRUSt2 predicted metabolic pathways. This multivariate machine-learning approach significantly differentiated DEPR (n = 20) vs. NODEP (n = 20) (PERMANOVA P < 0.001) based on microbiome taxa clustering and neurocircuit-relevant metabolic pathway network analysis for GABA, butyrate, glutamate, monoamines, monosaturated fatty acids, and inflammasome components. Gut microbiome dysbiosis using ASV prevalence data may offer the diagnostic potential of using human metaorganism biomarkers to identify individuals with a depression phenotype.

Identification of a Signaling Mechanism by Which the Microbiome Regulates Th17 Cell-Mediated Depressive-Like Behaviors in Mice

OBJECTIVE

Microbiota dysbiosis has been linked to major depressive disorder, but the mechanisms whereby the microbiota modulates mood remain poorly understood. The authors tested whether specific changes in the microbiome modulate depressive-like behaviors.

METHODS

Stools from learned helpless, non-learned helpless, and non-shocked mice were analyzed by V4 16S RNA sequencing to identify gut bacteria associated with learned helplessness and to quantify the level of the quorum-sensing molecule autoinducer-2 (AI-2). T cells were analyzed by flow cytometry, and serum amyloid proteins (SAA) were analyzed by quantitative real-time polymerase chain reaction. Fecal transfer approach and administration of oleic acid and AI-2 were used to determine the effects of the microbiome and quorum-sensing molecules on depressive-like behaviors.

RESULTS

Mice deficient in segmented filamentous bacteria (SFB) were resilient to the induction of depressive-like behavior, and were resensitized when SFB was reintroduced in the gut. SFB produces the quorum-sensing AI-2 and promotes the production of SAA1 and SAA2 by the host, which increases T helper 17 (Th17) cell production. Th17 cells were required to promote depressive-like behaviors by AI-2, as AI-2 administration did not promote susceptibility to depressive-like behaviors or SAA1 and SAA2 production in Th17-deficient mice after stress. Oleic acid, an AI-2 inhibitor, exhibited antidepressant properties, reducing depressive-like behavior, intestinal SAA1 and SAA2 production, and hippocampal Th17 cell accumulation. Stool samples from 10 people with current depressive symptoms and 10 matched healthy control subjects were analyzed as well. Patients with current major depressive disorder exhibited increased fecal interleukin 17A, SAA, and SFB levels.

CONCLUSIONS

The study results reveal a novel mechanism by which bacteria alter mood.

Vegetarian diet and the risk of depression, anxiety, and stress symptoms: a systematic review and meta-analysis of observational studies

Previous studies reported inconsistent findings regarding the consumption of a vegetarian diet with mental health outcomes, specifically depression, anxiety and stress. A systematic review was conducted to summarize the current state of literature regarding our understanding of the association between a vegetarian diet and depression, anxiety and stress. A literature search was completed using Scopus, PubMed, and the Web of Science for relevant articles published prior to July 2020. Prospective cohort and cross-sectional studies conducted on adults reporting risk estimates for the consumption of a vegetarian diet, depression, anxiety, and stress were selected. A fixed effects or a random effects model was performed to pool effect sizes. Results from 13 publications (four cohort studies and nine cross-sectional studies) assessing the relationship between the consumption of a vegetarian diet and depression, anxiety and stress were included. The pooled effect size from 10 studies indicated no association between the consumption of a vegetarian diet and depression (pooled effect size: 1.02, 95% CI: 0.84-1.25, p = 0.817). Further, the pooled effect size from four studies suggests that a vegetarian diet is not associated with anxiety (pooled effect size: 1.09, 95% CI: 0.71-1.68, p = 0.678). Due to insufficient data for stress, we were not able to pool the results. Together, no significant associations were observed between the consumption of a vegetarian diet and depression or anxiety. Future cohort studies are needed to further investigate the effects of a vegetarian diet on these mental health outcomes.

Dietary Restrictions and Depressive Symptoms: Longitudinal Results from the Constances Cohort

Cross-sectional results have suggested a linear association between the number of dietary exclusions and depressive symptoms. This longitudinal study aimed to examine the direction of this association. Methods: In the population-based Constances cohort, depressive symptoms were defined by a score ≥19 on the Centre of Epidemiologic Studies-Depression (CES-D) scale. Diet was measured with a 24-item qualitative food frequency questionnaire (FFQ). Both variables were available at inclusion (from 2012 to 2014) and on follow-up (2015 for the CES-D and 2017 for diet). Food exclusion was categorized into five different groups: No exclusion, exclusion of one, two, three, or ≥4 food groups according to the self-reported number of food groups rarely or never consumed. Logistic regressions were conducted, either taking depressive symptoms as the outcome on follow-up with dietary exclusions at baseline as predictor or with the opposite, adjusting for age, sex, education, income, alcohol intake, smoking, physical activity, and anemia. The path analysis included outcomes and covariates in one model. Results: The median follow-up was three years. A total of 29,337 participants (53.4% women, 48.15 ± 12.9 y.o.) had complete CES-D data and 25,356 (53.56% women, 49.05 ± 12.8 y.o.) FFQ data. Dietary exclusion at inclusion predicted depressive symptoms at follow-up (odds ratio [95% confidence interval]: 2.35 [1.62–3.40] for ≥4 excluded items compared to no exclusions). Depressive symptoms at inclusion predicted dietary exclusions at follow-up (3.45 [1.93–6.16] for ≥4 excluded items). In the path analysis, the standardized estimate of the association between dietary exclusions at inclusion and depressive symptoms at follow-up was by far higher than the opposite (0.1863 and 0.00189, respectively, both p < 0.05). Conclusions: The association of dietary exclusion with subsequent depression is stronger than the opposite association.

The Importance of Marine Omega-3s for Brain Development and the Prevention and Treatment of Behavior, Mood, and Other Brain Disorders

Most of the global population is deficient in long-chain marine omega-3s. In particular, docosahexaenoic acid (DHA), a long-chain omega-3 fatty acid, is important for brain and eye development. Additionally, DHA plays a significant role in mental health throughout early childhood and even into adulthood. In the brain, DHA is important for cellular membrane fluidity, function and neurotransmitter release. Evidence indicates that a low intake of marine omega-3s increases the risk for numerous mental health issues, including Attention Deficit Hyperactivity Disorder (ADHD), autism, bipolar disorder, depression and suicidal ideation. Studies giving supplemental marine omega-3s have shown promise for improving numerous mental health conditions. This paper will review the evidence surrounding marine omega-3s and mental health conditions.

Associations of n-3, n-6 Fatty Acids Intakes and n-6:n-3 Ratio with the Risk of Depressive Symptoms: NHANES 2009-2016

Many studies have explored the association between n-3 fatty acids and depression, but research on the associations of n-6 fatty acids and n-6:n-3 ratio with depression is more scarce, and the results are controversial. Therefore, we conducted this cross-sectional study to explore the associations of n-3 and n-6 fatty acid intakes and n-6:n-3 ratio with the risk of depressive symptoms using data from National Health and Nutrition Examination Survey (NHANES) 2009–2016. Dietary data on n-3 and n-6 fatty acids were obtained through two 24-h dietary recall interviews, and were adjusted by energy. Depressive symptoms were measured by PHQ-9 (nine-item Patient Health Questionnaire). We applied logistic regression and restricted cubic spline models to assess the relationships of n-3 and n-6 fatty acids intake and n-6:n-3 ratio with the risk of depressive symptoms. A total of 17,431 individuals over 18 years old were enrolled in this study. In the multivariate-adjusted model 2, compared with the lowest category, the highest odd ratios (ORs) with 95% confidence intervals (CIs) for n-3 fatty acid intake and n-6:n-3 ratio were 0.71 (0.55–0.92) and 1.66 (1.10–2.50), and middle OR (95% CI) for n-6 fatty acid intake was 0.72 (0.56–0.92), respectively. Our study suggests that n-3 and n-6 fatty acids intake were inversely associated with the risk of depressive symptoms, while the n-6:n-3 ratio was positively associated with the risk of depressive symptoms.

Associations between dietary oleic acid and linoleic acid and depressive symptoms in perimenopausal women: The Study of Women's Health Across the Nation

OBJECTIVES

The aim of this study was to review the association of dietary intake of oleic and linoleic acids (OA and LA, respectively) with depressive symptoms in perimenopausal women.

METHODS

This cross-sectional study used data from the Study of Women's Health Across the Nation (SWAN). Linear and logistic regressions and restricted cubic spline models were performed to examine the association of intake of OA and LA with depression.

RESULTS

We included 2793 women 42 to 52 y of age in the present study. Intake of the two acids was positively associated with the Center for Epidemiologic Studies Depression Scale (CES-D) scores in unadjusted and age-, race/ethnicity-, total family income- and education-adjusted linear regression model. The fully adjusted regression coefficients were β = 0.089 and β = 0.145 for oleic and linoleic acid intake, respectively. OA and LA intake was positively associated with depressive symptoms (CES-D score ≥16) in unadjusted and age-, race/ethnicity-, total family income- and education-adjusted logistic regression model. The fully adjusted odds ratios (ORs) with 95% confidence intervals (CIs) of depressive symptoms were 1.994 (1.298-3.063) and 1.592 (1.047-2.421) for the highest versus lowest quartile of intake of OA and LA, respectively.

CONCLUSION

Intake of OA and LA may be positively associated with depressive symptoms in perimenopausal women.

The association between dietary pattern and depression in middle-aged Korean adults

BACKGROUND/OBJECTIVES

The association between dietary patterns and depression has been reported but the results have been inconsistent. This study was conducted to investigate the association between dietary patterns and depression in middle-aged Korean adults.

SUBJECTS/METHODS

The participants were selected from a community-based cohort, a subset of the Korean Genome and Epidemiology Study. Depression was assessed using the Korean version of the Beck Depression Inventory (BDI) and those with a BDI score ≥ 16 were defined as having depression. The subjects' food intakes over the year preceding the survey were estimated by using a validated semi-quantitative food frequency questionnaire. Dietary patterns were identified by using factor analysis. Multiple logistic regression was used to assess the association of dietary pattern with depression.

RESULTS

Among 3,388 participants, 448 (13.2%) were identified as having depression. We identified two major dietary patterns: 'Healthy' dietary pattern was characterized by high intakes of vegetables, soybeans, mushroom, seaweeds, white fish, shellfish and fruits and a low intake of white rice. 'Unhealthy' dietary pattern was characterized by high intakes of white rice, meats, ramen, noodles, bread and coffee and a low intake of rice with other grains. Compared with subjects in the lowest quartiles, those in the highest quartiles of the healthy dietary pattern had a significantly lower odds ratio (OR = 0.59, 95% CI: 0.42-0.82, P for trend = 0.0037) after adjusting for potential confounders. In contrast, the unhealthy dietary pattern was negatively associated with depression (OR = 1.65, 95% CI: 1.19-2.28, P for trend = 0.0021).

CONCLUSION

This results suggest that a healthy dietary pattern (rich in vegetables, soybeans, mushroom, seaweeds, white fish, shellfish, and fruits) is associated with low risk of depression. Whereas an unhealthy dietary pattern (rich in white rice, meats, ramen, noodles, bread, and coffee) is associated with a high risk of depression in middle-aged Korean adults.

A comprehensive metabolomics investigation of hippocampus, serum, and feces affected by chronic fluoxetine treatment using the chronic unpredictable mild stress mouse model of depression

A metabolomic investigation of depression and chronic fluoxetine treatment was conducted using a chronic unpredictable mild stress model with C57BL/6N mice. Establishment of the depressive model was confirmed by body weight measurement and behavior tests including the forced swim test and the tail suspension test. Behavioral despair by depression was reversed by four week-treatment with fluoxetine. Hippocampus, serum, and feces samples collected from four groups (control + saline, control + fluoxetine, model + saline, and model + fluoxetine) were subjected to metabolomic profiling based on ultra-high performance liquid chromatography-quadrupole-time-of-flight mass spectrometry. Alterations in the metabolic patterns were evident in all sample types. The antidepressant effects of fluoxetine appeared to involve various metabolic pathways including energy metabolism, neurotransmitter synthesis, tryptophan metabolism, fatty acid metabolism, lipid metabolism, and bile acid metabolism. Predictive marker candidates of depression were identified, including β-citryl-L-glutamic acid (BCG) and docosahexaenoic acid (DHA) in serum and chenodeoxycholic acid and oleamide in feces. This study suggests that treatment effects of fluoxetine might be differentiated by altered levels of tyramine and BCG in serum, and that DHA is a potential serum marker for depression with positive association with hippocampal DHA. Collectively, our comprehensive study provides insights into the biochemical perturbations involved in depression and the antidepressant effects of fluoxetine.

Adhering to a vegetarian diet may create a greater risk of depressive symptoms in the elderly male Chinese population

BACKGROUND

A vegetarian diet may be a risk factor for depression, but this relationship was unclear in the elderly Chinese population.

METHODS

Self-report data were gathered from 1051 elderly persons using the Cohort of Elderly Health and Environment Controllable Factors, which was created in West Anhui, China. The depressive symptoms were set as binary, ordinal, and continuous outcomes, respectively, whereas the dietary structures were computed as an ordinal variable and a dummy variable. Multiple logistic regression, ordinal regression, and linear regression were used to assess the relationship by adjusting the potential confounding variables with p-values of <0.1 in univariate analysis.

RESULTS

The elderly participants who had a vegetable-based diet had the highest GDS scores of 8.78 ± 6.894 (p = 0.001) and the highest rate of depression (32.9%, p = 0.003). After adjustment for the potential confounders, elderly men who had a vegetable-based diet had a higher rate of depression (OR[95%CI]: 1.62[1.07-2.46], 4.71[1.38-16.03]), more severe symptoms of depression (OR[95%CI]: 8.85[2.94-34.12]), and higher GDS scores (β[95%CI]: 1.46[0.70-2.22], 2.97[1.28-4.67]) than male participants who had a meat-based diet, but this was not the case in women.

LIMITATIONS

All data were self-reported. The study lacked quantitatively evaluated dietary intake. The duration of the current dietary structures and comorbidities were not reported. The cross-sectional study made the causal role uncertain.

CONCLUSIONS

Vegetarian diets may pose a greater risk of depressive symptoms among the elderly Chinese population, especially elderly men. Given the cross-sectional nature of this study, the causal role was uncertain. Further prospective studies, in particular among elderly women, are needed.

Depressive Symptoms and Vegetarian Diets: Results from the Constances Cohort

The association between depressive symptoms and vegetarian diets is controversial. This study examines the cross-sectional association between depressive symptoms and vegetarian diets while controlling for potential confounders. Among 90,380 subjects from the population-based Constances cohort, depressive symptoms were defined by a score ≥19 on the Centre of Epidemiologic Studies-Depression (CES-D) scale and diet types (omnivorous, pesco-vegetarian, lacto-ovo-vegetarian and vegan) were determined with a food frequency questionnaire. Associations between depressive symptoms and diet were estimated through logistic regressions adjusting for socio-demographics, other foods, alcohol and tobacco consumption, physical activity and health-related concerns; specificity analyses considered the exclusion of any other food group. Depressive symptoms were associated with pesco-vegetarian and lacto-ovo-vegetarian diets in multivariable analyses (Odds-Ratio [95% confidence interval]: 1.43 [1.19–1.72] and 1.36 [1.09–1.70], respectively), especially in case of low legumes intake (p for interaction < 0.0001), as well as with the exclusion of any food group (e.g., 1.37 [1.24–1.52], 1.40 [1.31–1.50], 1.71 [1.49–1.97] for meat, fish and vegetables exclusion, respectively). Regardless of food type, the Odds-Ratio of depressive symptoms gradually increased with the number of excluded food groups (p for trend < 0.0001). Depressive symptoms are associated with the exclusion of any food group from the diet, including but not restricted to animal products.

Longitudinal Association between n-3 Long-Chain Polyunsaturated Fatty Acid Intake and Depressive Symptoms: A Population-Based Cohort Study in Japan

It remains unclear whether n-3 long-chain polyunsaturated fatty acids (LCPUFA) have a preventive effect on depression in the general population. This study investigated the longitudinal association between n-3 LCPUFA intake and depressive symptoms in community-dwelling Japanese participants. The participants were aged 40–79 years at baseline in the cohort study, wherein examinations, including the assessment of depressive symptoms and nutritional status, were biennially conducted from 1997 to 2012. The subjects (n = 2335) who had a Center for Epidemiologic Studies Depression Scale (CES-D) score < 16 at the first examination and who participated in the follow-up study at least once were included in the analysis. The follow-up end point was the first onset (CES-D ≥ 16) or the last examination participation. Hazard ratios (95% CIs) for CES-D ≥ 16 were estimated using the adjusted Cox proportional hazards model. Overall, 22.1% participants showed depressive symptoms during follow-up (average; 8.1 years). Compared with the lowest tertile, the highest HR for EPA was 0.74 (0.60–0.93), and highest and middle HRs for DHA were 0.79 (0.63–0.98) and 0.80 (0.65–0.99) (P for trend = 0.009 and 0.032), respectively. Among populations with high fish consumption, higher n-3 LCPUFA intake may be associated with a low risk of depressive symptoms.

Exploring the association between whole blood Omega-3 Index, DHA, EPA, DHA, AA and n-6 DPA, and depression and self-esteem in adolescents of lower general secondary education

Purpose

Depression is common in adolescents and long-chain polyunsaturated fatty acids (LCPUFA) are suggested to be associated with depression. However, research in adolescents is limited. Furthermore, self-esteem has never been studied in relation to LCPUFA. The objective here was to determine associations of depression and self-esteem with eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), Omega-3 Index (O3I), n-6 docosapentaenoic acid (n-6 DPA, also called Osbond acid, ObA), n-3 docosapentaenoic acid (DPA), and arachidonic acid (AA) concentrations in blood of adolescents attending lower general secondary education (LGSE).

Methods

Baseline cross-sectional data from a krill oil supplementation trial in adolescents attending LGSE with an O3I ≤ 5% were analysed using regression models built with the BayesFactor package in R. Fatty acids and O3I were determined in blood. Participants filled out the Centre for Epidemiologic Studies Depression (CES-D) scale and the Rosenberg Self-Esteem scale (RSE).

Results

Scores indicative of depression (CES-D ≥ 16) were found in 29.4% of the respondents. Of all fatty acids, we found extreme evidence [Bayes factor (BF) > 100] for a weak negative association between ObA and depression score [− 0.16; 95% credible interval (CI) − 0.28 to − 0.04; BF₁₀ = 245], and substantial evidence for a weak positive association between ObA and self-esteem score (0.09; 95% CI, − 0.03 to 0.20; BF₁₀ = 4). When all fatty acids were put in one model as predictors of CES-D or RSE, all of the 95% CI contained 0, i.e., no significant association.

Conclusion

No evidence was found for associations of DHA, EPA and O3I with depression or self-esteem scores in LGSE adolescents with O3I ≤ 5%. The associations of higher ObA status with lower depression and higher self-esteem scores warrant more research.

Vegetarian diets and depressive symptoms among men

BACKGROUND

Vegetarian diets are associate with cardiovascular and other health benefits, but little is known about mental health benefits or risks.

AIMS

To determine whether self-identification of vegetarian dietary habits is associated with significant depressive symptoms in men.

METHOD

Self-report data from 9668 adult male partners of pregnant women in the Avon Longitudinal Study of Parents and Children (ALSPAC) included identification as vegetarian or vegan, dietary frequency data and the Edinburgh Post Natal Depression Scale (EPDS). Continuous and binary outcomes were assessed using multiple linear and logistic regression taking account of potential confounding variables including: age, marital status, employment status, housing tenure, number of children in the household, religion, family history of depression previous childhood psychiatric contact, cigarette and alcohol consumption.

RESULTS

Vegetarians [n = 350 (3.6% of sample)], had higher depression scores on average than non-vegetarians (mean difference 0.96 points [95%CI + 0.53, + 1.40]) and a greater risk for EPDS scores above 10 (adjusted OR = 1.67 [95% CI: 1.14,2.44]) than non-vegetarians after adjustment for potential confounding factors.

CONCLUSIONS

Vegetarian men have more depressive symptoms after adjustment for socio-demographic factors. Nutritional deficiencies (e.g. in cobalamin or iron) are a possible explanation for these findings, however reverse causation cannot be ruled out.

Antidepressant-Like Effect of Lipid Extract of Channa striatus in Postpartum Model of Depression in Rats

Postpartum depression affects 15% of women. Channa striatus, a freshwater fish, is consumed in local Malay population as a rejuvenating diet during postpartum period. This study evaluated the antidepressant-like effect of lipid extract of C. striatus fillet and its mechanism of action in female Sprague-Dawley rats in postpartum model of depression. The rats were ovariectomized and treated with high dose of progesterone and estradiol benzoate for 23 days to have hormone-simulated pregnancy. The day 24 and afterwards were considered as the postpartum period. During the postpartum period, lipid extract was administered at 125, 250, and 500 mg/kg through intraperitoneal route for 15 days. Fluoxetine (10 mg/kg) was used as the positive control. On postpartum day 15, the animals were tested in forced swimming test (FST) and open field test (OFT) followed by biochemical analysis. Withdrawal of hormone administration during the postpartum period induced depressive-like behavior in FST. Administration of lipid extract reversed that depressive-like behavior at 125, 250, and 500 mg/kg in FST. In OFT, it decreased the exploratory activity. The mechanism of the antidepressant-like effect may be mediated through the decrease in plasma corticosterone, increase in plasma oxytocin, and decrease in nuclear factor-kappa B in prefrontal cortex of rats.

The Relationship between Fatty Acids and Different Depression-Related Brain Regions, and Their Potential Role as Biomarkers of Response to Antidepressants

Depression is a complex disorder influenced by a variety of biological and environmental factors. Due to significant heterogeneity, there are remarkable differences in how patients respond to treatment. A primary objective of psychiatric research is to identify biological markers that could be used to better predict and enhance responses to antidepressant treatments. Diet impacts various aspects of health, including depression. The fatty acid composition of the Western diet, which has a high ratio of n-6:n-3 polyunsaturated fatty acids, is associated with increased incidence of depression. The brain is rich in lipids, and dietary fatty acids act within specific brain regions to regulate processes that impact emotional behavior. This manuscript reviews existing evidence demonstrating brain region-specific fatty acid profiles, and posits that specific fatty acids may serve as predictive biomarkers of response to antidepressants. Furthermore, increasing blood levels of certain fats, such as n-3s, via dietary intervention may serve as an adjunct to improve the efficacy of antidepressants. Notably, most of the existing research regarding fats and depression-related brain regions has focused on n-3s, as compared to n-6s, monounsaturated, and saturated fats. This review article will help guide future work investigating the relationships between fatty acids, brain regions, and antidepressant efficacy.

Polyunsaturated fatty acids and recurrent mood disorders: Phenomenology, mechanisms, and clinical application

A body of evidence has implicated dietary deficiency in omega-3 polyunsaturated fatty acids (n-3 PUFA), including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), in the pathophysiology and etiology of recurrent mood disorders including major depressive disorder (MDD) and bipolar disorder. Cross-national and cross-sectional evidence suggests that greater habitual intake of n-3 PUFA is associated with reduced risk for developing mood symptoms. Meta-analyses provide strong evidence that patients with mood disorders exhibit low blood n-3 PUFA levels which are associated with increased risk for the initial development of mood symptoms in response to inflammation. While the etiology of this n-3 PUFA deficit may be multifactorial, n-3 PUFA supplementation is sufficient to correct this deficit and may also have antidepressant effects. Rodent studies suggest that n-3 PUFA deficiency during perinatal development can recapitulate key neuropathological, neurochemical, and behavioral features associated with mood disorders. Clinical neuroimaging studies suggest that low n-3 PUFA biostatus is associated with abnormalities in cortical structure and function also observed in mood disorders. Collectively, these findings implicate dietary n-3 PUFA insufficiency, particularly during development, in the pathophysiology of mood dysregulation, and support implementation of routine screening for and treatment of n-3 PUFA deficiency in patients with mood disorders.

A review of recent evidence in human studies of n-3 and n-6 PUFA intake on cardiovascular disease, cancer, and depressive disorders: does the ratio really matter?

Polyunsaturated fatty acids (PUFAs) have been considered of great interest for human health due to their potential anti-inflammatory action that may protect from a number of chronic-degenerative diseases with an inflammatory pathogenesis. This review aimed to report the most updated evidence of both n-3 and n-6 PUFAs effect on cardiovascular disease, cancer, and depression in humans. Attention has been also paid to those studies exploring the effects of the ratio intake. Results from pooled analyses of human studies reported a general positive effect of n-3 PUFAs intake on all outcomes considered. In contrast, the role of n-6 PUFAs on human health needs to be better assessed in order to clearly identify which compound exerts beneficial/harmful effects. Only a limited number of clinical studies considered the n-3:n-6 PUFAs ratio, rather reporting contrasting results. A number of limitations when considering the ratio between these two families of PUFAs have risen.

Associations of the Ratios of n-3 to n-6 Dietary Fatty Acids With Longitudinal Changes in Depressive Symptoms Among US Women

In the present study, we examined longitudinal changes in self-reported depressive symptoms (and related domains) in relation to baseline intakes of n-3 fatty acids (absolute and relative to n-6 fatty acids). Sex-specific associations were evaluated in a prospective cohort of adults (n = 2,053) from Baltimore, Maryland, who were 30-64 years of age at baseline and were followed for a mean of 4.65 (standard deviation, 0.93) years (2004-2013). Using mean intakes of n-3 and n-6 fatty acids reported on two 24-hour dietary recalls, we estimated the ratios of n-3 to n-6 fatty acids for both highly unsaturated fatty acids (≥20 carbon atoms) (HUFAs) and polyunsaturated fatty acids (≥18 carbon atoms) (PUFAs). Outcomes included total and domain-specific scores on the 20-item Center for Epidemiologic Studies-Depression scale. Based on mixed-effects regression models, among women, both higher n-3 HUFA:n-6 PUFA and n-3 PUFA:n-6 PUFA ratios were associated with a slower rate of increase in total Center for Epidemiologic Studies-Depression scores over time. Higher n-3 HUFA:n-6 HUFA ratios were associated with slower increases in somatic complaints in men, whereas among women, higher n-3 HUFA:n-6 PUFA and n-3 PUFA:n-6 PUFA ratios were both linked to putative longitudinal improvement in positive affect over time. Among US adults, n-3:n-6 dietary fatty acid ratio was associated with longitudinal changes in depressive symptoms, with a higher ratio linked to a slower increase in depressive symptoms over time, particularly among women.

Dietary vitamin E and fat intake are related to Beck's depression score

OBJECTIVE

There is a high prevalence of depressive disorders in all regions of the world. The importance of dietary factors in the causation of depression is suggested from epidemiologic studies in Western countries, but evidence from non-Western populations are lacking. We aimed to assess the relationship between dietary factors with depression scores in a cohort from north eastern Iran.

METHODS

A total of 7172 subjects (2725 men and 4447 women) were recruited. Dietary intake was assessed using a 24-h dietary recall questionnaire, and depressive symptoms were assessed using the Beck's depression questionnaire.

RESULTS

The age of the population samples were 49.3 ± 8.2 years for the male and 48.1 ± 8.0 years for the female subgroups. Crude intake of MUFA, SFA and TFA in patients was associated with depression scores. On the other hand, there were significant correlations between depression score and total energy adjusted intake of trans-fatty acid (TFA), cholesterol, vitamin E (p < 0.01 for all parameters).

CONCLUSION

There was an association between diet and depression score among a representative sample of individuals from north eastern Iran, with MUFA intake being inversely related, and vitamin E intake being directly related to Beck's depression score. However it cannot be determined whether this is related to the causation of depression in this cross sectional study.

Metabolomic identification of biochemical changes induced by fluoxetine and imipramine in a chronic mild stress mouse model of depression

Metabolomics was applied to a C57BL/6N mouse model of chronic unpredictable mild stress (CMS). Such mice were treated with two antidepressants from different categories: fluoxetine and imipramine. Metabolic profiling of the hippocampus was performed using gas chromatography-mass spectrometry analysis on samples prepared under optimized conditions, followed by principal component analysis, partial least squares-discriminant analysis, and pair-wise orthogonal projections to latent structures discriminant analyses. Body weight measurement and behavior tests including an open field test and the forced swimming test were completed with the mice as a measure of the phenotypes of depression and antidepressive effects. As a result, 23 metabolites that had been differentially expressed among the control, CMS, and antidepressant-treated groups demonstrated that amino acid metabolism, energy metabolism, adenosine receptors, and neurotransmitters are commonly perturbed by drug treatment. Potential predictive markers for treatment effect were identified: myo-inositol for fluoxetine and lysine and oleic acid for imipramine. Collectively, the current study provides insights into the molecular mechanisms of the antidepressant effects of two widely used medications.

Unsaturated fat intakes and mental health outcomes in young women from the Australian Longitudinal Study on Women’s Heath

Objective

To determine if associations exist between a range of unsaturated fatty acid intakes and mental health outcomes.

Design

Cross-sectional data analysis of the Australian Longitudinal Study on Women’s Health (ALSWH) Young Cohort Survey 3 that included the validated seventy-four-item Dietary Questionnaire for Epidemiological Studies FFQ, validated mental health scales and self-report questions on depression and anxiety.

Setting

Australia, 2003.

Subjects

A nationally representative sample of young Australian women (25–30 years) from ALSWH. The 7635 women with plausible energy intakes (>4·5 but <20·0 MJ/d) were included in the analyses.

Results

Adjusted logistic regression analyses found statistically significant associations between higher intakes of α-linolenic acid and decreased likelihood of depressive symptoms indicated by the ten-item Center for Epidemiological Studies Depression Scale (CESD-10; OR=0·77; 95 % CI 0·60, 0·99; P=0·040) and the Short Form Health Survey (SF-36) mental health subscale (OR=0·73 95 % CI 0·56, 0·96; P=0·024). Furthermore, higher intakes of n-6 fatty acids (OR=0·96, 95 % CI 0·93, 0·99; P=0·019) and linoleic acid (OR=0·96, 95 % CI 0·93, 0·99; P=0·020) were associated with decreased likelihood of self-reported diagnosed anxiety and higher intakes of n-9 fatty acids (OR=1·02, 95 % CI 1·00, 1·04; P=0·041) and oleic acid (OR=1·02, 95 % CI 1·00, 1·05; P=0·046) were associated with increased likelihood of self-reported diagnosed anxiety.

Conclusions:

Increased intakes of α-linolenic acid were associated with a reduced likelihood of depressive symptoms, increased intakes of n-6 fatty acids and linoleic acid were associated with a reduced likelihood of self-reported anxiety, and increased intakes of n-9 fatty acids and oleic acid were associated with an increased likelihood of anxiety. Additional studies are needed to further elucidate associations between unsaturated fatty acids and depression and anxiety.

ω-3 fatty acid intakes are inversely related to elevated depressive symptoms among United States women

Evidence that depressive symptoms are inversely related to n-3 (ω-3) fatty acids is growing among United States adults. We assessed whether self-reported depressive symptoms were inversely associated with n-3 fatty acid intakes by using a cross-sectional study in 1746 adults (aged 30-65 y) in Baltimore City, MD (2004-2009). The 20-item Center for Epidemiologic Studies-Depression Scale (CES-D) was used, with a CES-D score ≥16 suggestive of elevated depressive symptoms (EDS). By using the mean of two 24-h dietary recalls, n-3 highly unsaturated fatty acids (HUFAs; ≥20 carbons), n-3 polyunsaturated fatty acids (PUFAs; ≥18 carbons), and plausible ratios with n-6 (ω6) fatty acids were estimated. EDS prevalence was 18.1% among men and 25.6% among women. In women, the uppermost tertile (tertile 3) of n-3 PUFAs (compared with tertile 1) was associated with reduced odds of EDS by 49%, with a substantial sex differential. The n-3 PUFA:n-6:PUFA ratio was inversely related to EDS among women (tertile 2 vs. tertile 1, OR: 0.74; 95% CI: 0.41, 1.32; tertile 3 vs. tertile 1, OR: 0.47; 95% CI: 0.27, 0.83). A similar pattern was noted for n-3 HUFA:n-6 HUFA among women. For CES-D subscales, n-3 PUFA (% of energy) was inversely related to somatic complaints, whereas positive affect was directly related to n-3 HUFA (% of energy; total population and among women), n-3 HUFA:n-6 HUFA (women), and n-3 HUFA:n-6 PUFA (total population and among women). In sum, among United States women, higher intakes of n-3 fatty acids [absolute (n-3) and relative to n-6 fatty acids (n-3:n-6)] were associated with lower risk of elevated depressive symptoms, specifically in domains of somatic complaints (mainly n-3 PUFAs) and positive affect (mainly n-3 HUFAs).

Fish and fat intake and prevalence of depressive symptoms during pregnancy in Japan: baseline data from the Kyushu Okinawa Maternal and Child Health Study

The present study aimed to examine the relationship between consumption of meat, fish, and specific types of fatty acids and the prevalence of depressive symptoms during pregnancy in Japan. Study subjects were 1745 pregnant women. Depressive symptoms were defined as present when subjects had a Center for Epidemiologic Studies Depression Scale score of 16 or higher. Information on dietary factors was collected using a self-administered diet history questionnaire. The prevalence of depressive symptoms during pregnancy was 19.3%. Higher intake levels of fish, eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) were independently associated with a lower prevalence of depressive symptoms during pregnancy: the adjusted odds ratios (ORs) between extreme quartiles (95% confidence intervals [CIs], P for trend) were 0.61 (0.42-0.87, 0.01), 0.66 (0.46-0.95, 0.02) and 0.64 (0.44-0.93, 0.007), respectively. Higher intake levels of total fat and saturated fatty acids were independently related to a higher prevalence of depressive symptoms during pregnancy: the adjusted ORs between extreme quartiles (95% CIs, P for trend) were 1.42 (1.00-2.03, 0.06) and 1.74 (1.22-2.49, 0.001), respectively. There were no significant associations between intake of monounsaturated fatty acids, n-3 polyunsaturated fatty acids (PUFAs), α-linolenic acid, n-6 PUFAs, linoleic acid, arachidonic acid, or cholesterol or the ratio of n-3 to n-6 PUFA intake and depressive symptoms during pregnancy. Intake levels of fish, EPA, and DHA may be inversely associated with depressive symptoms during pregnancy while intake levels of total fat and saturated fatty acids may be positively related to depressive symptoms during pregnancy.

Pharmacometabolomic mapping of early biochemical changes induced by sertraline and placebo

In this study, we characterized early biochemical changes associated with sertraline and placebo administration and changes associated with a reduction in depressive symptoms in patients with major depressive disorder (MDD). MDD patients received sertraline or placebo in a double-blind 4-week trial; baseline, 1 week, and 4 weeks serum samples were profiled using a gas chromatography time of flight mass spectrometry metabolomics platform. Intermediates of TCA and urea cycles, fatty acids and intermediates of lipid biosynthesis, amino acids, sugars and gut-derived metabolites were changed after 1 and 4 weeks of treatment. Some of the changes were common to the sertraline- and placebo-treated groups. Changes after 4 weeks of treatment in both groups were more extensive. Pathway analysis in the sertraline group suggested an effect of drug on ABC and solute transporters, fatty acid receptors and transporters, G signaling molecules and regulation of lipid metabolism. Correlation between biochemical changes and treatment outcomes in the sertraline group suggested a strong association with changes in levels of branched chain amino acids (BCAAs), lower BCAAs levels correlated with better treatment outcomes; pathway analysis in this group revealed that methionine and tyrosine correlated with BCAAs. Lower levels of lactic acid, higher levels of TCA/urea cycle intermediates, and 3-hydroxybutanoic acid correlated with better treatment outcomes in placebo group. Results of this study indicate that biochemical changes induced by drug continue to evolve over 4 weeks of treatment and that might explain partially delayed response. Response to drug and response to placebo share common pathways but some pathways are more affected by drug treatment. BCAAs seem to be implicated in mechanisms of recovery from a depressed state following sertraline treatment.

Dietary intake of fish and PUFA, and clinical depressive and anxiety disorders in women

Fish and PUFA consumption are thought to play a role in mental health; however, many studies do not take into account multiple sources of PUFA. The present study analysed data from a sample of 935 randomly selected, population-based women aged 20–93 years. A validated and comprehensive dietary questionnaire ascertained the consumption of n-3 and n-6 PUFA. Another assessed fish and energy intake and provided data for a dietary quality score. The General Health Questionnaire-12 (GHQ-12) measured psychological symptoms and a clinical interview (Structured Clinical Interview for DSM-IV-TR Research Version, Non-patient edition) assessed depressive and anxiety disorders. Median dietary intakes of long-chain n-3 fatty acids (310 mg/d) were below suggested dietary target levels. The only PUFA related to categorical depressive and anxiety disorders was DHA. There was a non-linear relationship between DHA intake and depression; those in the second tertile of DHA intake were nearly 70% less likely to report a current depressive disorder compared to those in the first tertile. The relationship of DHA to anxiety disorders was linear; for those in the highest tertile of DHA intake, the odds for anxiety disorders were reduced by nearly 50% after adjustments, including adjustment for diet quality scores, compared to the lowest tertile. Those who ate fish less than once per week had higher GHQ-12 scores, and this relationship was particularly obvious in smokers. These are the first observational data to indicate a role for DHA in anxiety disorders, but suggest that the relationship between DHA and depressive disorders may be non-linear.

Chronic mild restraint stress rats decreased CMKLR1 expression in distinct brain region

Inflammation contributes to the pathophysiology of depression. Chemokine-like receptor-1 (CMKLR1) plays an important role both in the development of inflammation and in the mechanism of antidepressant effect of Omega-3 polyunsaturated fatty acids (Omega-3 PUFAs), ecosapeatanolicacid (EPA). The present study was to investigate the modification of CMKLR1 in chronic restraint stress (CRS) rats. CMKLR1 was examined in different brain region from CRS rats by using western blot and quantitative real-time PCR. The CMKLR1 expression in the hippocampus, prefrontal cortex and cerebellum was determined on 3, 7, 10 and 21 days of repeated restraint stress and was compared to controls. The results showed that the protein and mRNA level of CMKLR1 in the prefrontal cortex and hippocampus were significantly increased on day 3 and then decreased on day 7, 10 and 21 in the CRS rats. The protein and mRNA level of CMKLR1 in cerebellum was similar to that of control group throughout the whole experiment. Changed expression of brain CMKLR1 is suggested to be involved in the mechanism of depression.

Modeling depression in adult female cynomolgus monkeys (Macaca fascicularis)

Depressive disorders are prevalent, costly, and poorly understood. Male rodents in stress paradigms are most commonly used as animal models, despite the two-fold increased prevalence of depression in women and sex differences in response to stress. Although these models have provided valuable insights, new models are needed to move the field forward. Social stress-associated behavioral depression in adult female cynomolgus macaques closely resembles human depression in physiological, neurobiological, and behavioral characteristics, including reduced body mass, hypothalamic-pituitary-adrenal axis perturbations, autonomic dysfunction, increased cardiovascular disease risk, reduced hippocampal volume, altered serotonergic function, decreased activity levels, and increased mortality. In addition, behaviorally depressed monkeys also have low ovarian steroid concentrations, even though they continue to have menstrual cycles. Although this type of ovarian dysfunction has not been reported in depressed women and is difficult to identify, it may be the key to understanding the high prevalence of depression in women. Depressive behavior in female cynomolgus monkeys is naturally occurring and not induced by experimental manipulation. Different social environmental challenges, including isolation vs. subordination, may elicit the depression-like response in some animals and not others. Similarly, social subordination is stressful and depressive behavior is more common in socially subordinate monkeys. Yet, not all subordinates exhibit behavioral depression, suggesting individual differences in sensitivity to specific environmental stressors and enhanced risk of behavioral depression in some individuals. The behavior and neurobiology of subordinates is distinctly different than that of behaviorally depressed monkeys, which affords the opportunity to differentiate between stressed and depressed states. Thus, behaviorally depressed monkeys exhibit numerous physiological, neurobiological, and behavioral characteristics same as those of depressed human beings. The nonhuman primate model represents a new animal model of depression with great promise for furthering our understanding of this prevalent and debilitating disease and identifying novel therapeutic targets.

Fast-food and commercial baked goods consumption and the risk of depression

OBJECTIVE

Whereas the relationship between some components of diet, such as n-3 fatty acids and B-vitamins, and depression risk has been extensively studied, the role of fast-food or processed pastries consumption has received little attention.

DESIGN

Consumption of fast food (hamburgers, sausages, pizza) and processed pastries (muffins, doughnuts, croissants) was assessed at baseline through a validated semi-quantitative FFQ. Participants were classified as incident cases of depression if they reported a physician diagnosis of depression or the use of antidepressant medication in at least one of the follow-up questionnaires. Cox regression models were fit to assess the relationship between consumption of fast food and commercial baked goods and the incidence of depression.

SETTING

The SUN (Seguimiento Universidad de Navarra - University of Navarra Follow-up) Project, Spain.

SUBJECTS

Participants (n 8964) from a Spanish cohort.

RESULTS

After a median follow-up of 6·2 years, 493 cases of depression were reported. A higher risk of depression was associated with consumption of fast food (fifth (Q5) v. first quintile (Q1): hazard ratio (HR) = 1·36; 95 % CI 1·02, 1·81; P trend = 0·003). The results did not change after adjustment for the consumption of other food items. No linear relationship was found between the consumption of commercial baked goods and depression. Participants belonging to consumption quintiles Q2-Q5 showed an increased risk of depression compared with those belonging to the lowest level of consumption (Q1; HR = 1·38; 95 % CI 1·06, 1·80).

CONCLUSIONS

Fast-food and commercial baked goods consumption may have a detrimental effect on depression risk.

Dietary intake of omega-3 fatty acids and risk of depressive symptoms in adolescents

BACKGROUND

Previous randomized controlled trials have demonstrated that omega-3 polyunsaturated fatty acids (n-3 PUFA) are beneficial in reducing symptoms of depression. However, there is limited evidence regarding the influence of dietary n-3 PUFA intake on mood in adolescents drawn from population studies.

OBJECTIVE

In the present investigation, we examined the relationship between dietary n-3 PUFA intake on depression symptomatology in a large prospective pregnancy cohort followed for 17 years.

METHODS

Adolescents enrolled in the Western Australian Pregnancy Cohort (Raine) Study completed a Food Frequency Questionnaire to assess dietary fatty acid intake, as well as other dietary factors at age 14 and a fasting blood sample was taken. Participants also completed the Beck Depression Inventory for Youth (BDI-Y) at age 14 (N = 1,407) and at age 17 (N = 995).

RESULTS

An inverse relationship was observed between intake of both saturated fat and of n-3 PUFA at age 14 and BDI-Y scores at both 14 and 17 years of age. However, after adjusting for energy (kJ) intake and other lifestyle confounders, the relationships were no longer significant.

CONCLUSIONS

Associations previously reported between n3 PUFA and depressive symptoms may be due to collinearity with other dietary and lifestyle factors.

Dietary fat intake and the risk of depression: the SUN Project

Emerging evidence relates some nutritional factors to depression risk. However, there is a scarcity of longitudinal assessments on this relationship.

OBJECTIVE

To evaluate the association between fatty acid intake or the use of culinary fats and depression incidence in a Mediterranean population.

MATERIAL AND METHODS

Prospective cohort study (1999-2010) of 12,059 Spanish university graduates (mean age: 37.5 years) initially free of depression with permanently open enrolment. At baseline, a 136-item validated food frequency questionnaire was used to estimate the intake of fatty acids (saturated fatty acids (SFA), polyunsaturated fatty acids (PUFA), trans unsaturated fatty acids (TFA) and monounsaturated fatty acids (MUFA) and culinary fats (olive oil, seed oils, butter and margarine) During follow-up participants were classified as incident cases of depression if they reported a new clinical diagnosis of depression by a physician and/or initiated the use of antidepressant drugs. Cox regression models were used to calculate Hazard Ratios (HR) of incident depression and their 95% confidence intervals (CI) for successive quintiles of fats.

RESULTS

During follow-up (median: 6.1 years), 657 new cases of depression were identified. Multivariable-adjusted HR (95% CI) for depression incidence across successive quintiles of TFA intake were: 1 (ref), 1.08 (0.82-1.43), 1.17 (0.88-1.53), 1.28 (0.97-1.68), 1.42 (1.09-1.84) with a significant dose-response relationship (p for trend = 0.003). Results did not substantially change after adjusting for potential lifestyle or dietary confounders, including adherence to a Mediterranean Dietary Pattern. On the other hand, an inverse and significant dose-response relationship was obtained for MUFA (p for trend = 0.05) and PUFA (p for trend = 0.03) intake.

CONCLUSIONS

A detrimental relationship was found between TFA intake and depression risk, whereas weak inverse associations were found for MUFA, PUFA and olive oil. These findings suggest that cardiovascular disease and depression may share some common nutritional determinants related to subtypes of fat intake.

Depression and altered serum lipids in cynomolgus monkeys consuming a Western diet

Research over the past 15 years has suggested a high comorbidity of depression and coronary heart disease (CHD). However the mechanisms responsible for this relationship are poorly understood. This study was designed to examine the relationships between depressive behaviors and concentrations of circulating lipids and lipid signaling molecules that may be common to both CHD and depression in a cohort of cynomolgus monkeys (Macaca fascicularis) consuming a 'Western' diet, enriched with saturated fat and cholesterol. Socially-housed adult female cynomolgus monkeys (n=36) were fed the Western diet for 27 months and depressive behavior was recorded weekly. Body weight, body mass index and circulating cholesterol profiles were measured in all animals, and fatty acids (FA) and FA-based signaling molecules were measured in the 6 least and 6 most depressed monkeys. Monkeys consuming the Western diet exhibited a broad range of percent time spent in depressive behavior. The percent time spent depressed was positively correlated with total plasma and LDL cholesterol and negatively correlated with HDL cholesterol. Despite being leaner, depressed monkeys had higher concentrations of monounsaturated fats (C16:1 and C17:1), a higher ω6/ω3 polyunsaturated fatty acid (PUFA) ratio and higher concentrations of omega-6 (ω6) PUFAs, particularly C18:2ω6 and C20:3ω6. FA ratios suggest that stearoyl CoA desaturase 1 activity was increased in depressed monkeys. Depressed female cynomolgus monkeys had elevated concentrations of serum lipids and lipid signaling molecules that are typically associated with obesity, insulin resistance and cardiovascular disease, which may account in part for the comorbidity of depression and CHD.