Association between carbohydrate nutrition and prevalence of depressive symptoms in older adults

Effect of dietary fibre on cognitive function and mental health in children and adolescents: a systematic review and meta-analysis

Objective: The purpose of this study is to investigate the impact of dietary fibre on the mental health and cognitive function of children and adolescents. Methods: All interventional and observational studies that contained information on the relevant population (children and adolescents), intervention/exposures (high dietary fibre consumption) and outcomes (mental and cognitive parameters) were eligible. Eight electronic databases (Embase, Medline, Pubmed, Web of Science, Scopus, PsycINFO, Cochrane Library and ClinicalTrials.gov) were searched up to December 11, 2023. Results: A total of 15 studies (n = 4628) met inclusion criteria, consisting of 9 intervention trials and 6 observational studies. According to observational studies, higher dietary fibre consumption was associated with a 49% reduction in the odds of depression compared to lower intake (P < 0.0001; OR = 0.51; 95% CI: 0.38, 0.69; I2 = 0%). Furthermore, no significant correlations were found between dietary fibre consumption and intelligence or anxiety. Among intervention studies, no significant difference was observed between fibre supplementation and placebo in terms of anxiety (standardized mean difference (SMD): -0.23; 95% CI: -0.72, 0.27), stress (SMD: 0.03; 95% CI: -0.21, 0.28), memory (SMD: 0.46; 95% CI: -0.79, 1.71), or attention (SMD: -2.72; 95% CI: -6.30, 0.86). Conclusion: Evidence from observation studies demonstrated that higher dietary fibre consumption is associated with a decreased odds of depression symptoms, both in childhood and adolescence. However, the causal relationship between dietary fibre intake and mental and cognitive function in children and adolescents still requires further clarification through high-quality intervention studies in the future.

Gender Difference in the Impact of Total Energy Intake on the Association between Low Fiber Intake and Mental Health in Middle-Aged and Older Adults

The effect of dietary fiber intake on mental health is controversial. This study aimed to examine the association of fiber intake with mental health in Korean adults. This cross-sectional study included 11,288 participants aged ≥40 years who participated in the Korean Genome and Epidemiology Study (2004-2013). Fiber intake was assessed using a food frequency questionnaire and categorized into sex-specific quintiles. Multiple logistic regression models were used to investigate the association between the lowest quintile of fiber intake and poor mental health. Mental health was assessed using acute stress perception, the Psychosocial Well-Being Index-Short Form, self-rated health, and the Center for Epidemiological Studies-Depression Scale in Korea. Compared to those with higher fiber intake, having the lowest quintile of fiber intake was associated with higher odds of poor mental health risk, a higher risk of high-stress perception, poor psychosocial distress in males, poor psychosocial distress, and depression in females. Low fiber intake had profound negative mental health effects on males with high total energy intake and females with low total energy intake. In conclusion, there is a gender difference in the impact of total energy intake on the deleterious effect of low fiber intake on mental health.

Prevalence and risk factors for impaired activities of daily living in patients with neo-vascular age-related macular degeneration who present for anti-VEGF treatment

BACKGROUND/OBJECTIVES

To assess the prevalence and correlates of impaired activities of daily living (ADLs) in patients with neovascular age-related macular degeneration (nAMD) who present for anti-vascular endothelial growth factor (VEGF) therapy.

METHODS

In a clinic-based cohort of 437 patients with nAMD who presented for anti-VEGF therapy, the Older American Resources and Services Scale (OARS) was administered to assess for impairments in basic, instrumental and total ADL. Logistic regression analyses were conducted to determine odds ratios (OR) and 95% confidence intervals (CI) for factors associated with ADL impairment.

RESULTS

The prevalence of impaired basic, instrumental and total ADL was 37.76%, 67.82% and 39.59%, respectively. In multivariate-adjusted models, moderate visual impairment [OR 5.65, 95% CI (2.31-13.83) and blindness [OR 5.43, 95% CI (2.09-14.12)] were associated with greater odds of impaired total ADL. Depressive symptoms [OR 2.08, 95% CI (1.08-4.00)], the presence of any disability [OR 3.16, 95% CI (1.64-0.07)] and never driving [OR 4.00, 95% CI (1.60-10.00)] were also positively associated with total ADL impairment. Better vision-related quality of life (QoL) was inversely associated with impaired instrumental ADL whilst higher health-related QoL scores were associated with decreased odds of total ADL impairment.

CONCLUSIONS

There is a high prevalence rate of ADL impairment among nAMD patients presenting for therapy. Visual impairment, never driving, poor physical and mental health increased the odds of experiencing ADL impairment whilst better VRQoL and HRQoL reduced the odds of impairment.

Low-carbohydrate-diet score, dietary macronutrient intake, and depression among adults in the United States

BACKGROUND

The aim was to ascertain whether low-carbohydrate-diet (LCD) score and dietary macronutrient intake are associated with depression.

METHODS

This cross-sectional study included 23,204 United States adults from the National Health and Nutrition Examination Survey (NHANES) 2005-2018. Dietary macronutrient intake was evaluated by the average of two 24-h dietary recall interviews. LCD score was calculated by summing the 11 quantiles values of the percentages of energy derived from carbohydrate, protein, and fat. Major depression was defined as a nine-item Patient Health Questionnaire score of 10 or more. Logistic regression and restricted cubic spline models were used to explore the relationship between LCD score, dietary macronutrient intake, and depression.

RESULTS

LCD score was significantly associated with the risk of depression after adjustment for covariates (odds ratio, 0.98; 95 % confidence interval, 0.97-0.99; p < 0.001). Restricted cubic splines showed that the pattern of this inverse association was nonlinear. Among macronutrients, carbohydrate and protein intake was nonlinearly associated with the risk of depression, whereas fat intake was not related to the risk of depression. A decreased risk of depression was observed when the carbohydrate intake was moderate (45.3 %-59.1 %). The pattern of the association between protein intake and the risk of depression was L-shaped.

CONCLUSIONS

LCD score was inversely associated with the risk of depression in a nonlinear manner in a nationally representative sample of adults from the United States. Furthermore, moderate carbohydrate intake and high protein intake were correlated with a lower risk of depression.

Barriers to consumption of fruits and vegetables and strategies to overcome them in low- and middle-income countries: a narrative review

This review provides an overview of the barriers to the consumption of fruits and vegetables (FVs) as well as strategies to improve the intake of FVs in low- and middle-income countries (LMICs). The importance of the consumption of FVs and its role in disease prevention are discussed briefly. Trends in the consumption of FVs in LMICs are also summarised. The WHO recommends that every individual should consume at least five servings or 400 grams of FVs per day. Epidemiological and clinical investigations have demonstrated that FVs contain numerous bioactive compounds with health-protecting activities. Despite their health benefits, the intake of FVs in LMICs remains low. Major barriers identified were socio-demographic factors, environmental conditions, individual and cultural factors, and macrosystem influences. These barriers may be lowered at the household, school, community, and national level through multi-component interventions including behaviour change communication (BCC) initiatives, nutrition education (NE), gardening initiatives, farm to institution programs (FIPs), food baskets, cash transfers, nutrition-agriculture policy and program linkages, and food-market environment-based strategies. This review has research implications due to the positive outcomes of strategies that lower such barriers and boost consumption of FVs in LMICs.

Fiber intake and fiber intervention in depression and anxiety: a systematic review and meta-analysis of observational studies and randomized controlled trials

CONTEXT

Dietary fibers hold potential to influence depressive and anxiety outcomes by modulating the microbiota-gut-brain axis, which is increasingly recognized as an underlying factor in mental health maintenance.

OBJECTIVE

Evidence for the effects of fibers on depressive and anxiety outcomes remains unclear. To this end, a systematic literature review and a meta-analysis were conducted that included observational studies and randomized controlled trials (RCTs).

DATA SOURCES

The PubMed, Embase, CENTRAL, CINAHL, and PsychINFO databases were searched for eligible studies.

DATA EXTRACTION

Study screening and risk-of-bias assessment were conducted by 2 independent reviewers.

DATA ANALYSIS

Meta-analyses via random effects models were performed to examine the (1) association between fiber intake and depressive and anxiety outcomes in observational studies, and (2) effect of fiber intervention on depressive and anxiety outcomes compared with placebo in RCTs. A total of 181 405 participants were included in 23 observational studies. In cross-sectional studies, an inverse association was observed between fiber intake and depressive (Cohen's d effect size [d]: -0.11; 95% confidence interval [CI]: -0.16, -0.05) and anxiety (d = -0.25; 95%CI, -0.38, -0.12) outcomes. In longitudinal studies, there was an inverse association between fiber intake and depressive outcomes (d = -0.07; 95%CI, -0.11, -0.04). In total, 740 participants were included in 10 RCTs, all of whom used fiber supplements. Of note, only 1 RCT included individuals with a clinical diagnosis of depression. No difference was found between fiber supplementation and placebo for depressive (d = -0.47; 95%CI, -1.26, 0.31) or anxiety (d = -0.30; 95%CI, -0.67, 0.07) outcomes.

CONCLUSION

Although observational data suggest a potential benefit for higher fiber intake for depressive and anxiety outcomes, evidence from current RCTs does not support fiber supplementation for improving depressive or anxiety outcomes. More research, including RCTs in clinical populations and using a broad range of fibers, is needed.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42021274898.

Nordic diet and its benefits in neurological function: a systematic review of observational and intervention studies

Introduction

Neurological disorders have been considered the major contributors to global long-term disability and lower quality of life. Lifestyle factors, such as dietary patterns, are increasingly recognized as important determinants of neurological function. Some dietary behaviors, such as Nordic diet (ND) were likely to have protective effects on brain function. However, an understanding of the effectiveness of the ND pattern to improve neurological function and brain health is not fully understood. We review the current evidence that supports the ND pattern in various aspects of neurological function and addresses both proven and less established mechanisms of action based on its food ingredients and biochemical compounds.

Methods

In this systematic review, PubMed, Web of Science, and Scopus databases were searched from inception to February 2023. Observational and intervention studies were included.

Results

Of the 627 screened studies, 5 observational studies (including three cohorts and two cross-sectional studies) and 3 intervention studies investigating the association between ND and neurological function. Observational studies investigated the association of ND with the following neurological functions: cognition, stroke, and neuropsychological function. Intervention studies investigated the effects of ND on cognition and depression.

Discussion

Despite the limited literature on ND and its association with neurological function, several aspects of ND may lead to some health benefits suggesting neuroprotective effects. The current state of knowledge attributes the possible effects of characteristic components of the ND to its antioxidant, anti-inflammatory, lipid-lowering, gut-brain-axis modulating, and ligand activities in cell signaling pathways. Based on existing evidence, the ND may be considered a recommended dietary approach for the improvement of neurological function and brain health.

Systematic review registration

[https://www.crd.york.ac.uk/prospero/], identifier [CRD2023451117].

Characterizing the Discourse of Popular Diets to Describe Information Dispersal and Identify Leading Voices, Interaction, and Themes of Mental Health: Social Network Analysis

BACKGROUND

Social media has transformed the way health messages are communicated. This has created new challenges and ethical considerations while providing a platform to share nutrition information for communities to connect and for information to spread. However, research exploring the web-based diet communities of popular diets is limited.

OBJECTIVE

This study aims to characterize the web-based discourse of popular diets, describe information dissemination, identify influential voices, and explore interactions between community networks and themes of mental health.

METHODS

This exploratory study used Twitter social media posts for an online social network analysis. Popular diet keywords were systematically developed, and data were collected and analyzed using the NodeXL metrics tool (Social Media Research Foundation) to determine the key network metrics (vertices, edges, cluster algorithms, graph visualization, centrality measures, text analysis, and time-series analytics).

RESULTS

The vegan and ketogenic diets had the largest networks, whereas the zone diet had the smallest network. In total, 31.2% (54/173) of the top users endorsed the corresponding diet, and 11% (19/173) claimed a health or science education, which included 1.2% (2/173) of dietitians. Complete fragmentation and hub and spoke messaging were the dominant network structures. In total, 69% (11/16) of the networks interacted, where the ketogenic diet was mentioned most, with depression and anxiety and eating disorder words most prominent in the "zone diet" network and the least prominent in the "soy-free," "vegan," "dairy-free," and "gluten-free" diet networks.

CONCLUSIONS

Social media activity reflects diet trends and provides a platform for nutrition information to spread through resharing. A longitudinal exploration of popular diet networks is needed to further understand the impact social media can have on dietary choices. Social media training is vital, and nutrition professionals must work together as a community to actively reshare evidence-based posts on the web.

Dietary fiber intake, depression, and anxiety: a systematic review and meta-analysis of epidemiologic studies

BACKGROUND

Findings of previous studies on relationship between dietary fiber intake and depression were inconsistent. We performed a meta-analysis on the association of dietary fiber intake with depression and anxiety in epidemiologic studies.

METHODS

We conducted a systematic search of electronic databases, up to May 2021. Data from 18 publications (12 cross-sectional, five cohort and one case-control studies) on dietary fiber consumption in relation to depression or anxiety were included. For depression, fifteen studies were conducted on adults and three others on adolescents. Anxiety was not included in the analysis, due to insufficient eligible studies.

RESULTS

Total dietary fiber intake was associated with a 10% lower odds of depression (OR = 0.90; 95% confidence interval [CI]: 0.86, 0.95) in adults and a 57% lower odds (OR = 0.43, 95% CI: 0.32, 0.59) in adolescents. Dose-response meta-analysis revealed an inverse linear association between total dietary fiber intake and odd of depression in adults; such that each 5-g increase in total dietary fiber intake was associated with a 5% reduction in risk of depression (OR = 0.95; 95% CI: 0.94, 0.97). An inverse significant association was observed between intake of fiber from vegetables (OR = 0.73; 95% CI: 0.66, 0.82) and soluble fiber (OR = 0.80, 95% CI: 0.71, 0.91) and odds of depression. However, cereal fiber, fiber from fruits and insoluble fiber were marginally associated with a reduction in having depression.

CONCLUSIONS

High intake of dietary fiber was protectively associated with depression in adults, in a dose-response fashion.

Causal influence of dietary habits on the risk of major depressive disorder: A diet-wide Mendelian randomization analysis

BACKGROUND

Extensive observational evidence links diet quality to the risk for major depressive disorder (MDD), while clinical trials show that dietary improvement can improve depressive symptoms. However, due to issues with blinding dietary trials, confirming a causal relationship for diet's influence on MDD requires further research. Thus, we systemically investigated the bi-directional causal relationships between dietary habits and MDD by using two-sample Mendelian randomization (MR).

METHODS

We collected publicly available genome-wide association studies' summary statistics for dietary habits from UK Biobank (n = 449,210) and MDD from the Psychiatric Genomics Consortium (n = 142,646). We used a weighted median approach to synthesize MR estimates across genetic instruments. For the robustness of our results, we compared weighted median results with results from the inverse-variance weighted, the weighted mode, and MR-PRESSO.

RESULTS

There was moderate evidence that beef intake has a protective effect on MDD. There was weak but detectable evidence that cereal intake has a protective effect on MDD, while non-oily fish intake might increase the risk of MDD. We did not observe any causal effect of MDD on dietary habits.

LIMITATIONS

Our study may suffer from the violation of assumptions of MR due to horizontal pleiotropy; therefore, we did several sensitivity analyses to detect and minimize the bias.

CONCLUSIONS

In this two-sample MR analysis, we observed that higher beef intake may be protective against MDD. However, MDD did not appear to affect dietary habits. Potential mechanisms need to be further investigated to support our novel findings.

Association between food intake and mental health problems among preschoolers in China

Objective

Our knowledge of associations between specific types of food and mental health problems in preschool children, an important developmental period, remains scarce. Using a large sample size and a brief measure, we aimed to examine associations between food groups and mental health problems in preschoolers.

Methods

A descriptive cross-sectional study was conducted among 19,548 preschoolers in nine counties in China using a two-stage cluster sampling method. Information on food frequencies, physical activity, sedentary behavior, and sleep conditions was collected by a parent-reported questionnaire. Mental health status was assessed by a parent-reported Strength and Difficulty Questionnaire (SDQ). Height and weight were measured, and BMI was calculated. Relationships between specific types of food groups and mental health status were examined using multivariable regression modeling.

Results

Of the present study sample, 47.45% of children were girls. Boys had higher scores relating to total difficulties, conduct problems, hyperactivity, and peer problems than girls but lower scores in emotional symptoms and prosocial behavior. Children with more types of food categories tended to get lower SDQ total scores even after adjusting for confounding variables (p < 0.0001). The subscale scores of SDQ varied depending on the types and numbers of food consumed. Notably, boys' mental health problems were more likely to be associated with their consumed food type. Processed meat frequency intake among boys and girls was positively related to prosocial behavior (Girls: pickled food: p = 0.003, fried food: p < 0.0001, barbecued food: p = 0.006, smoked food: p = 0.005; Boys: pickled food: p = 0.3, fried food: p < 0.0001, barbecued food: p = 0.006, smoked food: p = 0.005) and negatively associated with the SDQ total and the other subscale scores (Girls: pickled food: p ≤ 0.02, fried food: p ≤ 0.005 except for emotions (p = 0.1), barbecued food: p ≤ 0.047, smoked food: p ≤ 0.04 (except for emotions (p = 0.06) and conduct behaviors (p = 0.2)); Boys: pickled food: p < 0.01 except for hyperactivity (p = 0.5), fried food: p ≤ 0.005 except for emotions (p = 0.1), barbecued food: p ≤ 0.007 except for hyperactivity (p = 0.8), smoked food: p ≤ 0.001 except for hyperactivity (p = 0.1) and peer problem (p = 0.08)). Adequate intake frequency of confectionery (2-4 times/week) was beneficial to their emotions, conduct, and total difficulties and was also beneficial for peer and prosocial behavior for boys (Girls: emotions: p = 0.02, conduct: p = 0.02, hyperactivity: p = 0.4, peer: p = 0.06, total difficulties: p = 0.01, prosocial behavior: p = 0.1; Boys: emotions: p = 0.009, conduct: p = 0.0009, hyperactivity: p = 0.7, peer: p = 0.02: total difficulties: p = 0.003, prosocial behavior: p = 0.0002).

Conclusion

Diverse food categories and adequate frequency of confectionery were found to be beneficial for children's mental health, with the exception of processed meat. These findings provide novel information and supportive data for children's dietary guidelines and the improvement of mental health.

Association Between Dietary Fiber Intake and Risk of Depression in Patients With or Without Type 2 Diabetes

BACKGROUND

Depression and type 2 diabetes (T2D) are both serious public health problems, with morbidity and mortality in people increasing year by year, resulting in a heavy economic burden. A correlation between dietary fiber and both has been reported. Nevertheless, few data are available concerning dietary fiber and the risk of depression with or without T2D, which deserve further attention.

MATERIALS AND METHODS

We assessed the relationship between dietary fiber intake and risk of depression with or without T2D in the 2007-2014 National Health and Nutrition Examination Survey (NHANES) population. A 24-h dietary review was used to assess fiber intake. The Patient Health Questionnaire-9 was used to assess depression. Stability of the results was assessed using restricted cubic spline models and logistic regression, as well as sensitivity analyses.

RESULTS

A total of 17,866 adults aged 20 years and older with a mean age of 49.3 ± 17.7 years were included in this study, of whom 49.5% were male. After adjusting for covariates, the association of dietary fiber intake with the risk of depression appeared to differ between non-T2D group and T2D group (OR, 0.987; 95% CI, 0.979-0.995 vs. OR, 1.003; 95% CI, 0.988-1.017). Furthermore, when dietary fiber was converted to a categorical variable, there was evidence of interaction between T2D status and fiber intake on decreasing the prevalence of depression (P-value for interaction = 0.015). Sensitivity analysis showed stable results.

CONCLUSION

Our findings indicated that whether a patient has T2D may affect the relationship between dietary fiber intake and the risk of depression, which still needs to be confirmed by further randomized controlled trials.

Cross-Sectional Associations of Intakes of Starch and Sugars with Depressive Symptoms in Young and Middle-Aged Japanese Women: Three-Generation Study of Women on Diets and Health

The relationship between the intakes of saccharide subtypes and depressive symptoms is unclear in Asian countries. This cross-sectional study aimed to investigate this association among 3963 young (age of 18 years) and 3826 middle-aged (mean age of 47.8 years) Japanese women. The intakes of starch, total sugars, free sugars, sucrose, lactose, glucose, and total fructose were assessed using a validated diet history questionnaire. The prevalence of depressive symptoms was 22.0% and 16.8% among young and middle-aged women, assessed using the Center for Epidemiologic Studies Depression (CES-D) score. After adjusting for potential confounding factors, higher starch intake was associated with a lower prevalence of depressive symptoms in young women with an odds ratio (OR) of the fourth to the first quintiles of 0.75 (95% confidence interval (CI): 0.57, 0.99). Moreover, higher intakes of sugars (except for lactose) were associated with a higher prevalence of depressive symptoms in young women, with ORs (95% CI) of the fifth to the first quintiles ranging from 1.30 (0.995, 1.69) for glucose to 1.47 (1.12, 1.93) for sucrose. These associations were not observed in middle-aged women. Future prospective studies are needed to confirm these findings.

Is the Sardinian Blue Zone the New Shangri-La for mental health? Evidence on depressive symptoms and its correlates in late adult life span

Background

An area of extraordinary longevity (i.e., Sardinian Blue Zone) characterized by a very high prevalence of long-lived successful agers has been validated in Sardinia, an Italian island located in the Mediterranean Sea.

Aims

This study was primarily aimed at examining whether dietary habits (intake of vegetables and fruit, animal-derived proteins, and carbohydrates-rich food), time spent on hobbies, subjective physical health, and socio-cultural context (Sardinian Blue Zone vs. another Sardinian rural area) predicted self-reported depressive symptoms in older adults recruited in the Sardinian Blue Zone and another Sardinian rural area not being characterized by a higher prevalence of long-lived individuals.

Methods

Three hundred and eighteen community-dwellers, age 65 years and older, 188 females and 130 males (M_age = 79.1 years, SD = 6.9 years) were recruited from the Sardinian Blue Zone and another Sardinian rural area. Each participant individually completed a battery of instruments to assess lifestyle, food habits, perceived physical health, and depressive symptoms through the CES-D inventory.

Results

Significant associations were found between depressive signs, perceived physical health, time spent gardening, proteins, and carbohydrates intake, respectively. Approximately 17% of the variance in the CES-D condition was predicted by socio-cultural context, perceived physical health, and gardening. Participants recruited in the Sardinian Blue Zone spent more time gardening and self-reported better physical health.

Conclusions

current results suggest that a socio-cultural context where people age well (i.e., the Sardinian Blue Zone), and a healthy and physically active lifestyle are crucial for promoting well-being in late adulthood.

NuMoOS – COVID-19 Nutrition and Mood Online Survey: Perception about dietary aspects, stress, anxiety, and depression in the social isolation of Coronavirus Disease 2019

Background

Methods

Results

Conclusions

Higher dietary glycemic load is inversely associated with stress prevalence among Iranian adults

BACKGROUND

Psychological disorders including depression, anxiety, and stress comprise a huge public health problem. The aim of this cross-sectional study is to assess the relationship between dietary glycemic index (DGI) and glycemic load (DGL) and mental disorders.

METHOD

Participants (n = 10,000) aged 20-69 were randomly selected from 200 clusters in Yazd from the recruitment phase of Yazd Health Study. The dietary intake of study participants was collected by a reliable and validated food frequency questionnaire consisting of 178 food items. DGI and DGL were calculated from the FFQ data using previously published reference values. To assess psychological disorders an Iranian validated short version of a self-reported questionnaire Depression Anxiety Stress Scales 21 was used.

RESULTS

There were no significant associations between DGI and DGL with odds of depression or anxiety in crude and adjusted models. However, individuals in the highest quartiles of DGL had the lowest odds of stress (OR: 0.69; 95% CI 0.47-1, P-trend = 0.023). This association remained significant after adjustment for potential confounding variables in model I (OR: 0.45; 95% CI 0.22-0.9, P-trend = 0.023), model II (OR: 0.46; 95% CI 0.22-0.96, P-trend = 0.039) and model III (OR: 0.46; 95% CI 0.22-0.96, P-trend = 0.042).

CONCLUSION

In conclusion, consumption of foods with higher GL was associated with lower odds of stress; however, no significant association was found between DGI or DGL and risk of depression and anxiety. Performing further studies with longitudinal design is suggested to confirm these results.

Carbohydrate-to-Fiber Ratio, a Marker of Dietary Intake, as an Indicator of Depressive Symptoms

OBJECTIVE

The aim of this study is to evaluate the association between a marker of dietary intake, the carbohydrate-to-fiber (CF) ratio, and moderate-to-severe depressive symptoms.

DESIGN

Cross-sectional study.

SETTING

National Health and Nutrition Examination Survey (NHANES) database from 2013-2016.

PARTICIPANTS

Individuals 18 years and older were included. Participants with total energy intake outside of three standard deviations of the mean, pregnant or breastfeeding women, and those with missing data were excluded.

MEASUREMENTS

The main independent variable, CF ratio, was generated using corresponding variables in NHANES and divided into quartiles. The main outcome was depressive symptoms using the Patient Health Questionnaire-9. Unadjusted and adjusted logistic regression analyses were used to calculate odds ratios and their corresponding 95% confidence interval (CI).  Results: Among all participants (n=9,728), 8.3% reported to have moderate-to-severe depressive symptoms (n=833). The highest proportion of depressive symptoms was reported in respondents in quartile 4 (Q4), with the highest CF ratio (13.0%; p<0.001). After adjustment, the odds of depressive symptoms significantly increased in Q4 of the CF ratio compared with Q1 (adjusted odds ratio 1.4, 95% CI 1.0-1.9). The prevalence of depressive symptoms significantly increased in females, lower federal poverty levels, non-married individuals, smokers, and hypertension patients.  Conclusion: This nationally representative sample suggests that a higher CF dietary intake ratio increases the risk of moderate-to-severe depressive symptoms. These results suggest that the CF ratio may help clinicians and patients evaluate their dietary risk for depressive symptoms. Further prospective studies are needed to validate this ratio as a dietary measurement.

Associations between different types and sources of dietary fibre intake and depressive symptoms in a general population of adults: a cross-sectional study

This cross-sectional study aimed to examine the associations between dietary fibre (DF) intake and depressive symptoms in a general adult population in Tianjin, China. A total of 24 306 participants (mean age 41 years; range 18-91 years) were enrolled. DF intake was assessed using a validated self-administered FFQ. Depressive symptoms were assessed using the Self-Rating Depression Scale. Associations between DF intake and depressive symptoms were estimated using logistic regression analysis. Socio-demographic, behavioural, health status and dietary factors were adjusted. In men, compared with participants in the lowest quartiles for total, soluble, vegetable and soya DF, OR for depressive symptoms in the highest were 0·83 (95 % CI 0·69, 0·99), 0·74 (95 % CI 0·63, 0·87), 0·79 (95 % CI 0·65, 0·96) and 0·69 (95 % CI 0·60, 0·81), respectively. In women, compared with participants in the lowest quartiles for vegetable and soya DF, the OR for depressive symptoms in the highest were 0·77 (95 % CI 0·64, 0·93) and 0·82 (95 % CI 0·70, 0·95), respectively. No association was found between total or soluble DF intake and depressive symptoms in women. No association was found between insoluble, cereal, fruit or tuber DF intake and depressive symptoms in men and women. Linear associations between DF intake and depressive symptoms were only detected for soya DF (men, β = -0·148, P < 0·0001; women, β = -0·069, P = 0·04). Results suggest that intake of soluble, vegetable and soya DF was inversely associated with depressive symptoms. These results should be confirmed through prospective and interventional studies.

Association between the level of adherence to dietary guidelines and depression among Korean patients with type 2 diabetes mellitus

OBJECTIVE

This study aimed to examine the cross-sectional association between adherence to dietary guidelines for type 2 diabetes mellitus (T2DM) and depression.

METHODS

A total of 3457 patients with T2DM were included. Dietary information was obtained using 24-h recall, and adherence to dietary guidelines was estimated using the Korean Diabetes Association-Korean Ministry of Health and Welfare index. Depression was evaluated using a questionnaire. Participants who had responded "yes" to any of the three questions related to diagnosis, current condition, and treatment were defined as depression. Multivariable logistic regression analysis was used to examine the association between adherence to dietary guidelines and depression.

RESULTS

T2DM patients with a lower score on adherence to dietary guidelines were more likely to report depression than those with a higher score (Odds ratios (OR): 0.51, 95% Confidence Interval (CI): 0.30-0.87). Patients with poor adherence to moderate calorie consumption (OR: 1.65, 95% CI: 1.07-2.52) and regular meal patterns (OR: 1.69, 95% CI: 1.15-2.50) were more likely to report depression. However, patients with poor adherence to low sodium intake were less likely to report depression (OR: 0.60, 95% CI: 0.40-0.88), and no association was observed between moderate carbohydrate consumption, sufficient vegetable/seaweed consumption, and moderate alcohol consumption and depression.

CONCLUSION

Good adherence to dietary guidelines was closely associated with a lower prevalence of depression among individuals with type 2 diabetes, but the specific guidelines were inconsistent. Systematic and continuous nutrition education for individuals with T2DM is necessary to improve their mental health outcomes.

Prevalence and risk factors for depressive symptoms in patients with neovascular age-related macular degeneration who present for anti-VEGF therapy

PURPOSE

To examine the prevalence and risk factors for depressive symptoms in patients with neovascular age-related macular degeneration (nAMD) presenting for anti-vascular endothelial growth factor (anti-VEGF) therapy.

METHODS

In a clinic-based cohort of 547 patients with nAMD who presented for treatment, the Centre of Epidemiological Studies Depression 10-point scale (CES-D-10) and Mental Health Index (MHI) component of the 36-item Short Form Survey were administered to assess for the presence of depressive symptoms. Logistic regression analyses were used to calculate odds ratios and 95% confidence intervals for factors associated with an increased likelihood of depressive symptoms.

RESULTS

The prevalence of depressive symptoms was 42.04% and 31.78% as per the CES-D-10 and MHI scales, respectively. Poor self-rated health (SRH) is associated with increased odds of depressive symptoms [multivariable-adjusted OR: 3.00 (95% CI 1.90-4.73) for CES-D-10; OR: 2.67 (95% CI 1.67-4.28) for MHI]. Impaired activities of daily living (ADLs) [multivariable-adjusted OR: 2.62 (95% CI 1.56-4.38) for CES-D-10; OR: 3.59 (95% CI 2.10-6.15) for MHI] and a visual function score within the two lowest quartiles were also associated with increased odds of depressive symptoms using both scales.

CONCLUSION

A high prevalence of depressive symptoms was observed among nAMD patients presenting for treatment. Poorer SRH, ADL impairment and reduced visual function were associated with increased odds of depressive symptoms.

Dietary fibre intake and its associations with depressive symptoms in a prospective adolescent cohort

Depression is a major cause of disability in adolescents. Higher dietary fibre intake has been associated with lower depressive symptoms in adults, but there is a lack of research in adolescents. We examined the association between dietary fibre intake (Commonwealth Scientific and Industrial Research Organisation (CSIRO) FFQ) and depressive symptoms (Beck Depression Inventory for Youth) in adolescents with prospective data from the Raine Study Gen2 14- and 17-year follow-ups (n 1260 and 653). Odds of moderate/extreme (clinically relevant) depressive symptoms by quartile of fibre intake were calculated using mixed-effects logistic regression for all participants, in a paired sample without moderate/extreme depressive symptoms at 14 years and in a sub-sample of participants with available inflammatory data at the ages of 14 and 17 years (n 718 and 547). Odds of moderate/extreme depressive symptoms were lower in the fourth (highest) quartile of overall fibre intake (OR 0·273, 95 % CI 0·09, 0·81) compared with the first (lowest) quartile, adjusting for sex, age, energy intake, adiposity, and family and lifestyle factors. However, further adjustment for dietary patterns attenuated the results. Associations of depressive symptoms with cereal or fruit and vegetable fibre intake were not significant in the final model. Adjustment for inflammation had no effect on OR. The association between a higher dietary fibre intake and lower odds of clinically relevant depressive symptoms may be more reflective of a high-fibre diet with all its accompanying nutrients than of an independent effect of fibre.

Consumption of Dietary Fiber in Relation to Psychological Disorders in Adults

Background: Previous observational studies suggested a relationship between dietary fiber consumption and mental health, but the findings were conflicting. We evaluated the link between dietary fiber intake and prevalence of depression, anxiety, and psychological distress among a large population of Iranian adults. Methods: A cross-sectional study among 3,362 Iranian adults working in 50 health centers was done. Data of dietary intakes were collected through a validated semiquantitative dish-based 106-item food frequency questionnaire (FFQ). Anxiety, depression, and psychological distress were defined based on the Iranian validated version of Hospital Anxiety and Depression Scale (HADS) and General Health Questionnaire (GHQ). Results: After adjustment for potential confounders, participants in the top quartile of total dietary fiber intake had a 33% and 29% lower risk of anxiety and high psychological distress [odds ratio (OR): 0.67; 95% CI: 0.48, 0.95 and OR: 0.71; 95% CI: 0.53, 0.94, respectively] compared to the bottom quartile of intake. The highest total dietary fiber intake was also inversely related to a lower risk of depression in women (OR: 0.63; 95% CI: 0.45, 0.88) but not in men. Among overweight or obese participants, higher intake of dietary fiber was related to a decreased risk of high psychological distress (OR: 0.52; 95% CI: 0.34, 0.79). A high level of dietary fiber intake was related to a lower risk of anxiety in normal-weight individuals (OR: 0.50; 95% CI: 0.31, 0.80). Conclusion: Significant inverse associations between total dietary fiber intake with anxiety and high psychological distress were found in Iranian adults. More consumption of dietary fiber was also related to reduced odds of depression in women. More investigations with prospective nature are needed to affirm these findings.

Association of dietary fiber and depression symptom: A systematic review and meta-analysis of observational studies

BACKGROUND

A potential relationship between depression and the intake of dietary fiber has been hypothesized in several studies. However, no meta-analysis has been conducted so far to explore the association between these two variables. Hence, we designed the present meta-analysis to elucidate the relationship between the intake of dietary fiber and depression.

METHODS

A comprehensive search was performed using the PubMed/Medline, Scopus, Web of Science and Google Scholar databases to identify any relevant studies published from inception to October 2019. Observational studies (cross-sectional and case-control) were included in the analysis.

RESULTS

Pooled analysis from the random-effects model of four case-control studies revealed that the consumption of dietary fiber in patients with depression was significantly lower versus healthy controls (WMD: -1.41 mg/dl, 95 % CI: -2.32, -0.51, P = 0.002). No significant heterogeneity was demonstrated among the analyzed studies (I² = 4.0 %, P = 0.37). By pooling 5 effect sizes of cross-sectional studies (with a total of 97,023 subjects), we demonstrated that a higher dietary consumption of fiber was associated with significantly lower odds of depression (OR = 0.76; 95 % CI: 0.64, 0.90; P = 0.010), with a low heterogeneity seen among the retrieved studies (I² = 43.9 %; P = 0.12).

CONCLUSION

An increased intake of total dietary fiber is associated with lower odds of depression. Further studies are needed to evaluate the relationship between the different types of dietary fiber and depression.

"Influence of diet on mood and social cognition: a pilot study"

Recently, a relationship has been observed between nutrition and social cognition. In this aspect, several dietary patterns, or even some probiotics, have been reported as social cognition modulators. However, to date, no studies have reported the effects of specific nutrients. Our aim was to evaluate the relationship between dietary macronutrients and the processing of social and affective information. Participants were undergraduates from the University of Extremadura (Badajoz, Spain) aged 21.3 ± 2.9 years., with a BMI of 22.8 ± 3.9 (kg m-2). The students' social cognition and diet were analysed through questionnaires and a dietary record. The diets were analysed with DIAL v.1.18® software (Alce Ingeniería®). The participants filled out the WHO-5 well-being index, Beck's anxiety inventory, Beck's depression inventory, ruminative response scale (RSS), Leiden index of depression sensitivity (LEIDS-r), empathy quotient (EQ), and interpersonal reactivity index (IRI). To analyse the data, nutrients were grouped through principal component analysis (PCA) into lipids, carbohydrates and proteins. Additionally, we assayed if these principal components were associated with psychological questionnaire scores using multiple linear regression analyses. The dietary pattern differed from the traditional Mediterranean diet due to high intake of proteins and saturated fatty acids. Regarding social cognition and macronutrients, we found a positive association between lipids, specifically cholesterol, and the Perspective-Taking Scale (an IRI component). Carbohydrates influenced the RSS, indicating that complex carbohydrates may be a risk factor for depression. Moreover, the brooding factor, a component of the RRS, was negatively affected by dietary carbohydrates and proteins, specifically by fiber and aspartate. Diet may influence several variables related to social cognition and mood. Particularly, a low-cholesterol diet rich in fiber, complex carbohydrates, and aspartate apparently provides benefits, improving the processing of social and affective information and psychic well-being.

Sources of Dietary Fiber Are Differently Associated with Prevalence of Depression

Dietary fiber has been actively studied for its profound impacts on mental health by affecting the gut–brain axis communication. However, the association between dietary fiber intake and depression has been inconsistent, partly due to the lack of consideration of the fiber source. Therefore, this study aimed to examine the association between various sources of dietary fiber and depression in Korean adults through a nationwide cross-sectional study. The study population was a total of 2960 adults between 19 and 64 years of age who participated in the Korean National Health and Nutrition Examination Survey (KNHANES, 2012–2016). Dietary fiber intake from each fiber subtype (crude, cereal, vegetable, fruit, seaweed, and mushroom) was calculated using the Food Frequency Questionnaire (FFQ). Depression prevalence was assessed using a Patient Health Questionnaire (PHQ-9) and self-reported clinical diagnosis by a physician. We found that seaweed (odds ratio (OR) = 0.38; 95% confidence interval (CI): 0.20–0.72; p < 0.05) and mushroom fiber intake (OR = 0.18; 95% CI: 0.01–0.37; p < 0.05) were inversely associated with depressive symptoms assessed using the PHQ-9 parameters. Moreover, seaweed fiber intake was inversely associated with clinical depression diagnosed by a physician (OR = 0.45; 95% CI: 0.23–0.88; p < 0.05). This was the first study to find that higher intakes of seaweed and mushroom fiber were associated with a lower likelihood of depression in a representative cohort of Korean adults, indicating that the specific source of dietary fiber may be an important dietary factor in modulating depression.

Dietary fiber and its associations with depression and inflammation

Dietary fiber is a crucial component of a healthy diet, with benefits that can be attributed to processes in the gut microbiota and the resulting by-products. Observational studies support associations between dietary fiber intake and depression and inflammation, but the potential mechanisms are poorly understood. This review examines evidence of the effects of dietary fiber on depression and inflammation and considers plausible mechanisms linking dietary fiber and depression, including microbiota-driven modification of gene expression and increased production of neurotransmitters. Additionally, inflammation may mediate the relationship between dietary fiber intake and depression. A high-fiber diet potentially lowers inflammation by modifying both the pH and the permeability of the gut. The resultant reduction in inflammatory compounds may alter neurotransmitter concentrations to reduce symptoms of depression. Further research into the link between dietary fiber intake and inflammation and depression is essential, as findings could potentially provide guidance for improvement in or prevention of inflammatory and depressive disorders.

Quality of Life: Psychological Symptoms-Effects of a 2-Month Healthy Diet and Nutraceutical Intervention; A Randomized, Open-Label Intervention Trial (RISTOMED)

Depression symptoms and lower health-related quality of life (HRQoL) are associated with inflammation. This multicenter dietary intervention was shown to reduce inflammation in older people. This was the main outcome. Here, we describe the effects on HRQoL, anxiety, and depressive symptoms according to inflammation status. Overall, 125 healthy older subjects (65–80 year) were recruited (Italy, France, and Germany) and randomized into four arms (A, Healthy diet (HD); B, HD plus De Simone Formulation probiotic blend; C, HD plus AISA d-Limonene; D, HD plus Argan oil). The HD was weight maintaining, rich in antioxidant vitamins, polyphenols, polyunsaturated fatty acids (n6: n3 ratio = 3:1), and fiber. Data on inflammatory parameters, mental (MCS) and physical (PCS) component summaries of HRQoL (SF−36), anxiety symptoms (STAI state), and depressive symptoms (CES-D) were collected before and after 56 days of intervention. Body fat mass proportion (BFM) was considered a co-variable. A decrease of CES-D score was seen in the four arms (A: −40.0%, p = 0.001; B: −32.5%, p = 0.023; C: −42.8%, p = 0.004; and D: −33.3%, p = 0.21). Within the subgroups of subjects with medium/high inflammation a similar decrease in CES-D score occurred in all groups (A: −44.8%, p = 0.021; B, −46.7%, p = 0.024; C, −52.2%, p = 0.039; D, −43.8%, p = 0.037). The effect of interventions on CES-D was not related to baseline inflammation. MCS-HRQoL improved in A and C. There was no change in anxiety or PCS-HRQoL. In this trial with no control group, a decrease in depressive symptoms in healthy older volunteers was observed after a 2-month healthy diet intervention, independently of inflammation but with possible limitations due to participation.

Association between dietary insulin index and load and psychological disorders

The present study was carried out to determine whether the dietary insulin index (DII) and dietary insulin load (DIL) are related to psychological disorders in a cross-sectional study among adults. A total of 3172 Iranian adults (age range of 18–55 years) were included. Data on dietary intakes were collected using a validated dish-based 106-item semi-quantitative FFQ. DII and DIL were calculated using food insulin index values published earlier. To assess depression and anxiety, an Iranian validated version of the Hospital Anxiety and Depression Scale was used. Furthermore, psychological distress was examined using the General Health Questionnaire. Among women, a significant positive association was seen; such that women in the highest quartile of DIL had higher odds of depression than those in the lowest quartile (OR 1·84; 95 % CI 1·14, 2·96). In terms of DII, in the fully adjusted model, women in the top quartile of DII were more likely to be depressed compared with those in the bottom quartile (OR 1·65; 95 % CI 1·05, 2·58). In conclusion, we found a significant positive association between DIL and DII and odds of depression among women, but not in men. However, such findings were not seen for anxiety and psychological distress.

A prospective analysis of dietary fiber intake and mental health quality of life in the Iowa Women's Health Study

OBJECTIVE

Recent studies have reported associations between dietary intake and mental health. Dietary fiber is one nutrient that may modulate mental health, specifically depression risk, through the gut microbiome. We prospectively examined the association between dietary fiber intake and mental health-related quality of life (QOL) scores, a proxy for depressive symptoms, in a cohort of 14,129 post-menopausal women in the Iowa Women's Health Study.

METHODS

Dietary intake was assessed at baseline [1986] using a 127-item food frequency questionnaire. Mental health-related QOL scores were assessed at the follow-up questionnaire [2004] using the Mental Health (MH) component and Mental Health Composite (MCS) scales derived from the SF-36 Health Survey. The association between dietary fiber intake and mean QOL scores was examined using linear regression, with adjustment for age, alcohol intake, energy intake, waist-to-hip ratio, physical activity, smoking status, and education.

RESULTS

The median dietary fiber intake was 19.0 g/day, ranging from 1.1 to 89.4 g/day. Multivariable-adjusted mean MH scores were higher among those with higher fiber intake (P _{for trend} = 0.02). For MCS score, the association with fiber intake observed in a model adjusted for age and energy intake became insignificant after multivariable adjustment.

CONCLUSIONS

Our study is one of the first prospective analyses of the association between higher dietary fiber intake and increased MH QOL scores later in life. Given a plausible biological mechanism underlying the association between fiber intake and mental health, additional studies are warranted.

Evidence available for patient-identified priorities in depression research: results of 11 rapid responses

OBJECTIVES

Patient priority setting projects (PPSPs) can reduce research agenda bias. A key element of PPSPs is a review of available literature to determine if the proposed research priorities have been addressed, identify research gaps, recognise opportunities for knowledge translation (KT) and avoid duplication of research efforts. We conducted rapid responses for 11 patient-identified priorities in depression to provide a map of the existing evidence.

DESIGN

Eleven rapid responses.

DATA SOURCES

Single electronic database (PubMed).

ELIGIBILITY CRITERIA

Each rapid response had unique eligibility criteria. For study designs, we used a stepwise inclusion process that started with systematic reviews (SRs) if available, then randomised controlled trials and observational studies as necessary.

RESULTS

For all but one of the rapid responses we identified existing SRs (median 7 SRs per rapid response, range 0-179). There were questions where extensive evidence exists (ie, hundreds of primary studies), yet uncertainties remain. For example, there is evidence supporting the effectiveness of many non-pharmacological interventions (including psychological interventions and exercise) to reduce depressive symptoms. However, targeted research is needed that addresses comparative effectiveness of promising interventions, specific populations of interest (eg, children, minority groups) and adverse effects.

CONCLUSIONS

We identified an extensive body of evidence addressing patient priorities in depression and mapped the results and limitations of existing evidence, areas of uncertainty and general directions for future research. This work can serve as a solid foundation to guide future research in depression and KT activities. Integrated knowledge syntheses bring value to the PPSP process; however, the role of knowledge synthesis in PPSPs and methodological approaches are not well defined at present.

Carbohydrate nutrition variables and risk of disability in instrumental activities of daily living

PURPOSE

We aimed to examine the prospective association between dietary glycemic index (GI) and glycemic load (GL) of foods consumed, intakes of carbohydrates and fiber, and the ability to perform activities of daily living (ADL) in older adults.

METHODS

A total of 844 participants from the Blue Mountains Eye Study aged 60 years or older were examined from 2002-2004 to 2007-2009. Dietary information was collected using a validated, semi-quantitative food-frequency questionnaire. The Older Americans Resources and Services activities of daily living scale were administered to assess the functional status of participants. Multivariable logistic regression analysis was performed.

RESULTS

After multivariable adjustment, participants who were in the second and third quartiles of energy-adjusted total fiber intake compared to those in the first quartile of intake (reference group) at baseline had reduced risk of incident impaired instrumental activities of daily living (IADL) 5 years later: OR, 0.39 (95% CI 0.22-0.70) and OR 0.54 (95% CI 0.30-0.95), respectively. Analyses that involved dichotomized total fiber intake showed that participants in the upper three quartiles of total fiber intake (> 19 g/day), compared to those in the lowest quartile of intake (≤ 19 g/day) or reference group, had reduced IADL disability risk 5 years later: OR 0.49 (95% CI 0.31-0.79). Non-significant associations were observed with total carbohydrates, GI, and GL and with risk of impaired total and basic ADL at 5-year follow-up.

CONCLUSIONS

Habitual fiber consumption might be beneficial in leading to improved health status subserving performance of instrumental daily activities, needed to function in the community.

Glycemic index, glycemic load, and depression: a systematic review and meta-analysis

BACKGROUND/OBJECTIVES

Although several studies have investigated the association between dietary Glycemic Index (GI), glycemic load (GL) and depression, results are inconsistent. This systematic review and meta-analysis was performed to summarize earlier evidence on the association between dietary GI, GL, and depression.

SUBJECTS/METHODS

We searched in PubMed/Medline, ISI Web of Knowledge, Scopus, EMBASE, and Google Scholar to identify related articles published until April 2018. Publications that fulfilled the following criteria were included in the current study: (1) publications with participants aged ≥ 18 years; (2) studies that considered GI or GL as the exposure; (3) studies that considered depression as the main outcome or as one of the outcomes; and (4) publications in which odds ratios (ORs) or mean difference were reported as the effect size. Finally, 11 studies, including 6 cross-sectional studies, 2 cohort studies, and 3 clinical trials were considered for inclusion in the systematic review, and 5 cross-sectional studies, 2 cohort studies, and 2 clinical trials (out of 11 studies included in the systematic review) were included in the meta-analysis. The quality of cross-sectional and cohort studies examined by the Newcastle-Ottawa Scale (NOS) and the quality of clinical trials examined using Cochrane Collaboration Risk of Bias tool. We also assessed the quality of evidence with the GRADE system.

RESULTS

Sample sizes of the included cross-sectional studies ranged from 140 to 87,618 participants, and in total 101,389 participants were included in 6 studies. In total, 85,500 participants were included in 2 cohort studies. Sample sizes of the included clinical trials ranged from 40 to 82 participants, and in total 164 participants were included in three studies. Combining seven effect sizes from five cross-sectional studies, no significant association was observed between dietary GI and odds of depression (OR: 1.01; 95% CI: 0.94, 1.08; I² = 80.2%; n = 5). We also failed to find any significant association between dietary GL and odds of depression (OR: 0.93; 95% CI: 0.84, 1.04; I² = 42%; n = 5). Combining two effects sizes from two cohort studies, there was a significant positive association between dietary GI and depression (HR: 1.13; 95% CI: 1.02, 1.25; I² = 86.1%, n = 2). In addition, combining two effect sizes from two clinical trials, we found a significant change in depression score after consumption of a high-GL diet (weighted mean difference (WMD): 0.66; 95% CI: 0.28, 1.04; I² = 0.0%, n = 2).

CONCLUSIONS

Summarizing earlier findings, we found no significant association between either dietary GI or GL and odds of depression in cross-sectional studies. However, a significant positive association was observed between dietary GI and depression in cohort studies. In addition, a significant effect of a high-GL diet consumption on risk of depression was seen in clinical trials.

Intake of Raw Fruits and Vegetables Is Associated With Better Mental Health Than Intake of Processed Fruits and Vegetables

Background: Higher intakes of fruits and vegetables, rich in micronutrients, have been associated with better mental health. However, cooking or processing may reduce the availability of these important micronutrients. This study investigated the differential associations between intake of raw fruits and vegetables, compared to processed (cooked or canned) fruits and vegetables, and mental health in young adults.

Methods: In a cross-sectional survey design, 422 young adults ages 18–25 (66.1% female) living in New Zealand and the United States completed an online survey that assessed typical consumption of raw vs. cooked/canned/processed fruits and vegetables, negative and positive mental health (depressive symptoms, anxiety, negative mood, positive mood, life satisfaction, and flourishing), and covariates (including socio-economic status, body mass index, sleep, physical activity, smoking, and alcohol use).

Results: Controlling for covariates, raw fruit and vegetable intake (FVI) predicted reduced depressive symptoms and higher positive mood, life satisfaction, and flourishing; processed FVI only predicted higher positive mood. The top 10 raw foods related to better mental health were carrots, bananas, apples, dark leafy greens like spinach, grapefruit, lettuce, citrus fruits, fresh berries, cucumber, and kiwifruit.

Conclusions: Raw FVI, but not processed FVI, significantly predicted higher mental health outcomes when controlling for the covariates. Applications include recommending the consumption of raw fruits and vegetables to maximize mental health benefits.

Exploration of the association between dietary fiber intake and depressive symptoms in adults

OBJECTIVE

Current evidence on the association between dietary fiber intake and the risk of depressive symptoms is inconsistent. Thus, the purpose of the present study was to explore their association.

METHODS

Data from the National Health and Nutrition Examination Survey 2007 to 2014 were used in this cross-sectional study. Dietary data were obtained through two 24-h dietary recall interviews. Depressive symptoms were assessed using Patient Health Questionnaire. Logistic regression models and restricted cubic spline models were applied to evaluate the associations among dietary intakes of total, cereal, vegetable, and fruit fiber and depressive symptoms.

RESULTS

A total of 16 807 adults ages 20 y or older were included in this study. Dietary intakes of total, cereal, vegetable, and fruit fiber were inversely associated with depressive symptoms in unadjusted model and multivariate-adjusted model 1. In multivariate-adjusted model 2, the odds ratios (95% confidence intervals) of depressive symptoms were 0.59 (0.44-0.79), 0.90 (0.69-1.19), 0.58 (0.45-0.76), and 0.64 (0.45-0.92) for the highest versus lowest quartile of total, cereal, vegetable, and fruit fiber intakes, respectively. Dose-response analyses found that the risk of depressive symptoms was associated with total fiber intake in a nonlinear manner, whereas the relationships were linear with cereal, vegetable, and fruit fiber intakes.

CONCLUSIONS

Our study suggested that intakes of total fiber, vegetable fiber, and fruit fiber were inversely associated with depressive symptoms. Further larger prospective studies are needed to confirm our findings.

Added sugars and sugar-sweetened beverage consumption, dietary carbohydrate index and depression risk in the Seguimiento Universidad de Navarra (SUN) Project

The association between added sugars or sugar-sweetened beverage consumption and the risk of depression, as well as the role of carbohydrate quality in depression risk, remains unclear. Among 15 546 Spanish university graduates from the Seguimiento Universidad de Navarra (SUN) prospective cohort study, diet was assessed with a validated 136-item semi-quantitative FFQ at baseline and at 10-year follow-up. Cumulative average consumption of added sugars, sweetened drinks and an overall carbohydrate quality index (CQI) were calculated. A better CQI was associated with higher whole-grain consumption and fibre intake and lower glycaemic index and consumption of solid (instead of liquid) carbohydrates. Clinical diagnoses of depression during follow-up were classified as incident cases. Multivariable time-dependent Cox regression models were used to estimate hazard ratios (HR) of depression according to consumption of added sugars, sweetened drinks and CQI. We observed 769 incident cases of depression. Participants in the highest quartile of added sugars consumption showed a significant increment in the risk of depression (HR=1·35; 95 % CI 1·09, 1·67, P=0·034), whereas those in the highest quartile of CQI (upper quartile of the CQI) showed a relative risk reduction of 30 % compared with those in the lowest quartile of the CQI (HR=0·70; 95 % CI 0·56, 0·88). No significant association between sugar-sweetened beverage consumption and depression risk was found. Higher added sugars and lower quality of carbohydrate consumption were associated with depression risk in the SUN Cohort. Further studies are necessary to confirm the reported results.

Sugar intake from sweet food and beverages, common mental disorder and depression: prospective findings from the Whitehall II study

Intake of sweet food, beverages and added sugars has been linked with depressive symptoms in several populations. Aim of this study was to investigate systematically cross-sectional and prospective associations between sweet food/beverage intake, common mental disorder (CMD) and depression and to examine the role of reverse causation (influence of mood on intake) as potential explanation for the observed linkage. We analysed repeated measures (23,245 person-observations) from the Whitehall II study using random effects regression. Diet was assessed using food frequency questionnaires, mood using validated questionnaires. Cross-sectional analyses showed positive associations. In prospective analyses, men in the highest tertile of sugar intake from sweet food/beverages had a 23% increased odds of incident CMD after 5 years (95% CI: 1.02, 1.48) independent of health behaviours, socio-demographic and diet-related factors, adiposity and other diseases. The odds of recurrent depression were increased in the highest tertile for both sexes, but not statistically significant when diet-related factors were included in the model (OR 1.47; 95% CI: 0.98, 2.22). Neither CMD nor depression predicted intake changes. Our research confirms an adverse effect of sugar intake from sweet food/beverage on long-term psychological health and suggests that lower intake of sugar may be associated with better psychological health.

Dietary Sugars and Endogenous Formation of Advanced Glycation Endproducts: Emerging Mechanisms of Disease

The rapid increase in metabolic diseases, which occurred in the last three decades in both industrialized and developing countries, has been related to the rise in sugar-added foods and sweetened beverages consumption. An emerging topic in the pathogenesis of metabolic diseases related to modern nutrition is the role of Advanced Glycation Endproducts (AGEs). AGEs can be ingested with high temperature processed foods, but also endogenously formed as a consequence of a high dietary sugar intake. Animal models of high sugar consumption, in particular fructose, have reported AGE accumulation in different tissues in association with peripheral insulin resistance and lipid metabolism alterations. The in vitro observation that fructose is one of the most rapid and effective glycating agents when compared to other sugars has prompted the investigation of the in vivo fructose-induced glycation. In particular, the widespread employment of fructose as sweetener has been ascribed by many experimental and observational studies for the enhancement of lipogenesis and intracellular lipid deposition. Indeed, diet-derived AGEs have been demonstrated to interfere with many cell functions such as lipid synthesis, inflammation, antioxidant defences, and mitochondrial metabolism. Moreover, emerging evidence also in humans suggest that this impact of dietary AGEs on different signalling pathways can contribute to the onset of organ damage in liver, skeletal and cardiac muscle, and the brain, affecting not only metabolic control, but global health. Indeed, the most recent reports on the effects of high sugar consumption and diet-derived AGEs on human health reviewed here suggest the need to limit the dietary sources of AGEs, including added sugars, to prevent the development of metabolic diseases and related comorbidities.