Habitual yoghurt consumption and depressive symptoms in a general population study of 19,596 adults

Probiotics and Prebiotics Affecting Mental and Gut Health

The effects of the gut microbiota on mental and intestinal health are an area of great interest. This study aimed to reveal the relationship between the intake of probiotic and prebiotic foods and mental and gut health. Data were obtained using an online survey from young adults (n = 538) enrolled at Afyonkarahisar Health Sciences University who agreed to participate in this study in the 2022-2023 academic year. This study included 538 participants, mostly (85.5%) females. Participants who never consumed yogurt had 7.614 times higher Gastrointestinal Symptom Rating Scale scores than those who consumed yogurt daily (p < 0.01). Similarly, the frequency of ayran consumption had a statistically significant effect on Bristol Stool Scale scores (p < 0.05). The ratio of normal defecation to constipation was 68.7% lower in participants who consumed ayran daily, whereas the ratio of diarrhea to constipation was 76.4% lower in participants who never consumed ayran. However, the frequency of prebiotic consumption did not have a significant effect on Bristol Stool Scale scores (p > 0.05). The consumption of probiotic and prebiotic foods exerted a significant effect on GSRS total scores and subfactors of the Depression Anxiety Stress Scale-42, namely depression, anxiety, and stress.

The Role of Gut Microbiota in Anxiety, Depression, and Other Mental Disorders as Well as the Protective Effects of Dietary Components

The number of individuals experiencing mental disorders (e.g., anxiety and depression) has significantly risen in recent years. Therefore, it is essential to seek prevention and treatment strategies for mental disorders. Several gut microbiota, especially Firmicutes and Bacteroidetes, are demonstrated to affect mental health through microbiota-gut-brain axis, and the gut microbiota dysbiosis can be related to mental disorders, such as anxiety, depression, and other mental disorders. On the other hand, dietary components, including probiotics (e.g., Lactobacillus and Bifidobacterium), prebiotics (e.g., dietary fiber and alpha-lactalbumin), synbiotics, postbiotics (e.g., short-chain fatty acids), dairy products, spices (e.g., Zanthoxylum bungeanum, curcumin, and capsaicin), fruits, vegetables, medicinal herbs, and so on, could exert protective effects against mental disorders by enhancing beneficial gut microbiota while suppressing harmful ones. In this paper, the mental disorder-associated gut microbiota are summarized. In addition, the protective effects of dietary components on mental health through targeting the gut microbiota are discussed. This paper can be helpful to develop some dietary natural products into pharmaceuticals and functional foods to prevent and treat mental disorders.

Relationship between dietary pattern and depressive symptoms: an international multicohort study

BACKGROUND

Several previous studies have shown that dietary patterns are associated with the incidence of depressive symptoms. However, the results have been inconsistent. This study aimed to prospectively investigate the association between dietary patterns and the risk of depressive symptoms in two large cohort studies.

METHODS

The Tianjin Chronic Low-grade Systemic Inflammation and Health (TCLSIH) cohort study included a total of 7,094 participants living in Tianjin, China from 2013 to 2019, and the UK Biobank cohort study includes 96,810 participants who were recruited from 22 assessment centers across the UK taken between 2006 and 2010. All participants were free of a history of cardiovascular disease (CVD), cancer, and depressive symptoms at baseline. Dietary patterns at baseline were identified with factor analysis based on responses to a validated food frequency questionnaire in TCLSIH or Oxford WebQ in UK Biobank. Depressive symptoms were evaluated using the Chinese version of the Zung Self-Rating Depression Scale (SDS) in TCLSIH or hospital inpatient records in UK Biobank. Cox proportional hazards regression models were used to estimate the association between dietary patterns and depressive symptoms.

RESULTS

A total of 989, and 1,303 participants developed depressive symptoms during 17,410 and 709,931 person-years of follow-up. After adjusting for several potential confounders, the multivariable HRs (95% CIs) of the depressive symptoms were 0.71 (0.57, 0.88) for traditional Chinese dietary pattern, 1.29 (1.07, 1.55) for processed animal offal included animal food dietary pattern, and 1.22 (1.02, 1.46) for sugar rich dietary pattern in TCLSIH (all Q4 vs Q1). In the UK Biobank, the HRs (95% CIs) of depressive symptoms were 1.39 (1.16, 1.68) for processed food dietary pattern (Q4 vs Q1), 0.90 (0.77, 1.00) for healthy dietary pattern (Q3 vs Q1), and 0.89 (0.75, 1.05) for meat dietary pattern (Q4 vs Q1) in the final adjusted model.

CONCLUSION

Dietary patterns rich in processed foods were associated with a higher risk of depressive symptoms, and following a traditional Chinese dietary pattern or healthy dietary pattern was associated with a lower risk of depressive symptoms, whereas meat dietary pattern was not associated.

Fermented dairy foods consumption and depressive symptoms: A meta-analysis of cohort studies

BACKGROUND

The gut-brain axis has been potentially proposed as a link between the intake of fermented dairy foods and depression. We carried out this meta-analysis on published cohort studies to estimate the overall depression risk of fermented dairy foods intake.

METHODS

We searched the CNKI (China National Knowledge Infrastructure) and PubMed databases for all articles within a range of published years from 2010 to 2022 on the association between fermented dairy foods intake and depression.

RESULTS

Finally, 8 studies met the inclusion criteria for this study, with 83,533 participants. Overall, there was statistical evidence of significantly decreased depression risk was found to be associated with fermented dairy foods intake (OR = 0.89, 95% CI = 0.81-0.98). In subgroup analysis, cheese and yogurt consumptions were significantly associated with decreased depression risk (OR = 0.91, 95% CI = 0.84-0.98 for cheese and OR = 0. 84, 95% CI = 0.72-0.99 for yogurt). However, we failed to find superabundant intake of fermented dairy foods intake decreased the risk of depression.

CONCLUSION

Our meta-analysis indicated that fermented dairy foods intake may have potential beneficial effect on depression via the gut-brain axis.

Nonfermented Dairy Intake, but Not Fermented Dairy Intake, Associated with a Higher Risk of Depression in Middle-Age and Older Finnish Men

BACKGROUND

Despite the putative health benefits of fermented dairy products, evidence on the association between fermented dairy and nonfermented dairy intake, and depression incidence is limited.

OBJECTIVES

This study examined cross-sectional and prospective associations between total dairy, fermented dairy, and nonfermented dairy intake with 1) the presence of elevated depressive symptoms and 2) the risk of a future hospital discharge or outpatient diagnosis of depression.

METHODS

Data from 2603 Finnish men (aged 42-60 y), recruited as part of the Kuopio Ischaemic Heart Disease Risk Factor Study, were included. Multivariable logistic regression models were used to examine ORs and 95% CIs for elevated depressive symptoms (Human Population Laboratory scale ≥5 points) at baseline. Cox proportional hazards regression models were used to estimate HRs and 95% CIs between dairy categories and risk of depression diagnoses.

RESULTS

In cross-sectional analyses, fermented dairy intake in the highest (compared with lowest) tertile was associated with lower odds of having elevated depressive symptoms (adjusted OR: 0.70; 95% CI: 0.52, 0.96). Each 100-g increase in nonfermented dairy intake was associated with higher odds of having elevated depressive symptoms (adjusted OR: 1.06; 95% CI: 1.01, 1.10). During a mean follow-up time of 24 y, 113 males received a diagnosis of depression. After excluding cheese intake, higher fermented dairy intake was associated with a lower risk of depression diagnosis (adjusted HR: 0.62; 95% CI: 0.38, 1.03), which was strengthened after excluding those with elevated depressive symptoms at baseline (adjusted HR: 0.55; 95% CI: 0.31, 0.99), whereas nonfermented dairy intake in the highest tertile was associated with a 2-fold higher risk of depression (adjusted HR: 2.02; 95% CI: 1.20, 3.42).

CONCLUSIONS

Fermented dairy and nonfermented dairy intake were differentially associated with depression outcomes when examined cross-sectionally and over a mean period of 24 y. These findings suggest that dairy fermentation status may influence the association between dairy intake and depression in Finnish men. The KIHD study was registered at clinicaltrials.gov as NCT03221127.

Association Between Consumption of Fermented Food and Food-Derived Prebiotics With Cognitive Performance, Depressive, and Anxiety Symptoms in Psychiatrically Healthy Medical Students Under Psychological Stress: A Prospective Cohort Study

Background

Gut microbiota-based therapeutic strategies, such as probiotic and prebiotic preparations, may benefit mental health. However, commonly consumed fermented and prebiotic-containing foods have not been well-tested. The aim of the present study was to determine whether consumption of fermented food and food-derived prebiotics is associated with cognitive performance, depressive, and anxiety symptoms in psychiatrically healthy medical students under psychological stress.

Methods

The study protocol with data analysis plan was prospectively registered. Food consumption was evaluated with a 7-day dietary record. Cognitive performance was modeled with academic examination performance in relation to subject knowledge. Pre-exam depressive and anxiety symptoms were assessed with the Patient Health Questionnaire-9 and Generalized Anxiety Disorder-7, respectively.

Results

In total, 372 medical students (22.7 ± 1.1 years of age, 66% female) completed the study. No relationship was observed between cognitive performance under stress and either fermented food (adjusted β 0.02, 95% CI −0.07–0.11, p = 0.63) or food-derived prebiotics consumption (adjusted β −0.00, 95% CI −0.09–0.09, p = 0.99). High intake of fermented food was associated with more severe depressive (adjusted β 0.11, 95% CI 0.01–0.20, p = 0.032) and anxiety symptoms under stress (adjusted β 0.13, 95% CI 0.04–0.22, p = 0.0065); however, no such link was observed for food-derived prebiotics (adjusted β 0.03, 95% CI −0.07–0.13, p = 0.50 and −0.01, 95% CI −0.11–0.08, p = 0.83, for depression and anxiety, respectively).

Conclusions

Under psychological stress in medical students, consumption of fermented food and food-derived prebiotics appears to be not associated with cognitive performance. High intake of fermented food, but not food-derived prebiotics, may be associated with severity of depressive and anxiety symptoms. The safety of fermented food in this regard therefore requires further clarification.

The association between dairy products and psychological disorders in a large sample of Iranian adults

BACKGROUND

Dairy products contain certain nutrients that are useful in mental disorders. This study aimed to assess the associations between dairy products and psychological disorders in a large sample of Iran, a Middle Eastern country.

METHODS

This cross-sectional study was undertaken on 7387 adults. Data on dietary intakes were obtained using a validated Food Frequency Questionnaire. Psychological health was assessed by the Iranian validated version of depression, anxiety, and stress scale 21. Multivariable logistic regression analysis was performed to analyze the association between dairy intake and psychological disorders.

RESULTS

After adjustment for potential confounders, total milk consumption (OR for the highest vs. lowest tertile: 0.73, 0.58-0.92) and total yogurt consumption (0.78, 0.62-0.97) were associated with decreased odds of depression. An inverse relationship was found between total dairy (0.73, 95% CI 0.590.91), total milk (0.72; 0.58-0.88), kashk (0.79, 0.65-0.96), and yogurt drink (0.80, 95% CI 0.65-0.98) consumption and anxiety symptoms. Higher intake of cheese was related to greater odds of stress (1.52, 1.02-2.26). No association was found between the consumption of high-fat dairy, low-fat dairy, low-fat milk, low-fat yogurt, high-fat yogurt, cheese, kashk, yogurt drink, and depression. Also, there is no association between dairy products and stress symptoms. This association was significant among men and women and high-fat and low-fat products in the total adjusted stratified analysis models.

CONCLUSIONS

Findings of this study revealed that both high-fat and low-fat dairy products are associated with a reduced prevalence of psychological disorders. Still, more prospective studies are required to confirm these associations.

Possible use of fermented foods in rehabilitation of anorexia nervosa: the gut microbiota as a modulator

Anorexia nervosa is a serious psychiatric disorder with high morbidity and mortality rate. Evidence for the optimal psychopharmacological approach to managing the disorder remains limited, with nutritional treatment, focused on weight restoration through the consumption of high energy diet, regarded as one of the fundamental steps in treatment. The human gut microbiome is increasingly recognised for its proposed role in gastrointestinal, metabolic, immune and mental health, all of which may be compromised in individuals with anorexia nervosa. Dietary intake plays an important role in shaping gut microbiota composition, whilst the use of fermented foods, foods with potential psychobiotic properties that deliver live bacteria, bacterial metabolites, prebiotics and energy, have been discussed to a lesser extent. However, fermented foods are of increasing interest due to their potential capacity to affect gut microbiota composition, provide beneficial bacterial metabolites, and confer beneficial outcomes to host health. This review provides an overview of the role of the gut microbiota in relation to the disease pathology in anorexia nervosa and especially focuses on the therapeutic potential of fermented foods, proposed here as a recommended addition to the current nutritional treatment protocols warranting further investigation.

Associations of different types of dairy intakes with depressive symptoms in adults

BACKGROUND

Current evidence on the associations between different types of milk products and depressive symptoms is few and controversial, and there has been no study focusing on different types of milk (whole-fat, low-fat, and skim). This study aimed to appraise their associations.

METHODS

This cross-sectional study included adults (N=21,924) from the National Health and Nutrition Examination Survey 2007-2016. Patient Health Questionnaire was used to evaluate depressive symptoms. Logistic regression model was implemented to assess the association of dairy consumption with depressive symptoms.

RESULTS

After multivariate adjustment, compared to non-consumers, the odds ratios (95% confidence intervals) of depressive symptoms for intake < 175.38 g/d and 175.38 to < 321.56 g/d of skim milk were 0.48 (0.27-0.85) and 0.46 (0.29-0.75), and 0.70 (0.55-0.88) for intake < 81.00 g/d of milk desserts, while 1.61 (1.05-2.46), 1.70 (1.15-2.50) and 1.55 (1.11-2.16) for intake < 129.63 g/d, 129.63 to < 289.75 g/d and ≥ 289.75 g/d of whole milk, respectively. These associations remained significant in stratified analyses by gender and age. Additionally, yogurt was negatively associated with depressive symptoms in both females and the age group (≥ 60 years). Low-fat milk was inversely associated with depressive symptoms for both males and the age group (≥ 60 years). Moderate creams intake was negatively associated with depressive symptoms in males.

LIMITATIONS

It was difficult to infer causality for a cross-sectional study.

CONCLUSIONS

Intakes of skim milk and moderate milk desserts were negatively associated with depressive symptoms, while whole milk was positively associated with depressive symptoms among adults.

The association between banana consumption and the depressive symptoms in Chinese general adult population: A cross-sectional study

BACKGROUND

Banana contains many kinds of substances that are beneficial to depressive symptoms. However, there are no epidemiological researches directly to explore the association between banana consumption and depressive symptoms. This study aimed to investigate whether the banana consumption is related to depressive symptoms in a general adult population.

METHODS

A cross-sectional study was performed in 24,673 adults in Tianjin. Banana consumption was evaluated via a validated food frequency questionnaire. Depressive symptoms were assessed by using Self-Rating Depression Scale (SDS). The association between banana consumption and depressive symptoms was analyzed by multiple logistic regression analysis.

RESULTS

The prevalence of depressive symptoms was 16.1% in males and 18.4% in females (SDS ≥ 45), respectively. In males, comparing to the reference group (almost never), the multivariable adjusted odds ratios (ORs) (95% confidence intervals) of depressive symptoms across banana consumption were 0.86 (0.74, 0.99) for <1 time/week, 0.76 (0.66, 0.88) for 1-3 times/week and 0.97 (0.82, 1.16) for ≥4 times/week. By contrast, the multivariable adjusted ORs (95% confidence intervals) were 1.11 (0.94, 1.32) for <1 time/week, 0.99 (0.85, 1.16) for 1-3 times/week and 1.22 (1.02, 1.46) for ≥4 times/week in females. Similar association was observed when other cut-offs (SDS ≥ 48 and 50) were used to define depressive symptoms.

LIMITATION

This is a cross-sectional study, causality remains unknown.

CONCLUSION

Findings from this study suggested a negative association between moderate banana consumption and depressive symptoms in males. In females, high banana consumption is positively related to depressive symptoms.

Is dairy consumption associated with depressive symptoms or disorders in adults? A systematic review of observational studies

Diet quality is associated with depression risk, however the possible role of dairy products in depression risk is unclear. A number of epidemiological studies have examined associations between dairy consumption and depressive symptoms, but results have been inconsistent. Therefore, this systematic review aimed to examine whether an association exists between dairy consumption and depressive symptoms or disorders in adults. Anxiety symptoms were also explored as a secondary outcome. CINAHL, Cochrane, MEDLINE complete, EMBASE, Scopus and PsycINFO databases were searched from database inception to December 2018. Studies were included if they used a case-control, cross-sectional, or cohort study design, and included community dwelling or institutionalized adults (≥18 years). Seven prospective and six cross-sectional studies (N = 58,203 participants) reported on the association between dairy consumption and depressive symptoms or disorders. Findings were mixed, with one study reporting a positive association; five studies reporting no association; and seven studies reporting mixed associations depending on dairy type, gender or population group. We found conflicting and inconsistent associations in studies that were generally of fair quality. Future longitudinal and intervention studies that employ more rigorous dietary assessment methods are warranted.

Mediators of Intervention Effects on Depressive Symptoms Among People Living With HIV: Secondary Analysis of a Mobile Health Randomized Controlled Trial Using Latent Growth Curve Modeling

Background

Although several studies have investigated the effects of mobile health (mHealth) interventions on depression among people living with HIV, few studies have explored mediators of mHealth-based interventions to improve mental health in people living with HIV. Identifying influential mediators may enhance and refine effective components of mHealth interventions to improve mental health of people living with HIV.

Objective

This study aimed to examine mediating factors of the effects of a mHealth intervention, Run4Love, designed to reduce depression among people living with HIV using 4 time-point measurement data.

Methods

This study used data from a randomized controlled trial of a mHealth intervention among people living with HIV with elevated depressive symptoms in Guangzhou, China. A total of 300 patients were assigned to receive either the mHealth intervention (n=150) or a waitlist control group (n=150) through computer-generated block randomization. Depressive symptoms, coping, and HIV-related stigma were measured at baseline, 3-, 6-, and 9-month follow-ups. The latent growth curve model was used to examine the effects of the intervention on depressive symptoms via potential mediators. Mediating effects were estimated using bias-corrected 95% bootstrapped CIs (BCIs) with resampling of 5000.

Results

Enhanced positive coping and reduced HIV-related stigma served as effective treatment mediators in the mHealth intervention. Specially, there was a significant indirect effect of the mHealth intervention on the slope of depressive symptoms via the slope of positive coping (beta=–2.86; 95% BCI –4.78 to –0.94). The indirect effect of the mHealth intervention on the slope of depressive symptoms via the slope of HIV-related stigma was also statistically significant (beta=–1.71; 95% BCI –3.03 to –0.40). These findings indicated that enhancement of positive coping and reduction of HIV-related stigma were important mediating factors of the mHealth intervention in reducing depression among people living with HIV.

Conclusions

This study revealed the underlying mediators of a mHealth intervention to reduce depression among people living with HIV using latent growth curve model and 4 time-point longitudinal measurement data. The study results underscored the importance of improving positive coping skills and mitigating HIV-related stigma in mHealth interventions to reduce depression among people living with HIV.

Association between habitual yogurt consumption and newly diagnosed non-alcoholic fatty liver disease

BACKGROUND/OBJECTIVES

Many studies have suggested that probiotics may be applied as a therapeutic agent for non-alcoholic fatty liver disease (NAFLD). However, the effects of frequent yogurt consumption (as a natural probiotic source) on NAFLD remain poorly understood. This study was to examine the association of habitual yogurt consumption with newly diagnosed NAFLD in the general adult population.

SUBJECT/METHODS

Overall, 24,389 adults were included in this cross-sectional study. Yogurt consumption was estimated by using a validated self-administered food frequency questionnaire. NAFLD was diagnosed by abdominal ultrasonography. We used logistic regression models to assess the association between yogurt consumption categories and newly diagnosed NAFLD.

RESULTS

The multivariable odds ratios with 95% confidence interval of newly diagnosed NAFLD were 1.00 (0.88, 1.14) for 1 time/week, 0.91 (0.81, 1.02) for 2-3 times/week, and 0.86 (0.76, 0.98) for ≥4 times/week (P for trend = 0.01), compared with those who consumed <1 time/week yogurt. The inverse association was observed in a sensitivity analysis.

CONCLUSION

Higher yogurt consumption was inversely associated with the prevalence of newly diagnosed NAFLD. These results are needed to be confirmed in randomized controlled trials or prospective studies.

The Stroke Stigma Scale: a reliable and valid stigma measure in patients with stroke

OBJECTIVE

The objective of the study is to analyse the psychometric properties of the Stroke Stigma Scale, a novel scale to assess perceived stigma of patients with stroke.

DESIGN

This is a psychometric study.

SETTING

Neurology or rehabilitation units in three hospitals in China.

SUBJECTS

A total of 288 patients with stroke.

INTERVENTIONS

None.

MEASURES

The content validity of the Stroke Stigma Scale was assessed through expert consultation. Criterion validity was evaluated based on the scale's relationships with the Stigma Scale for Chronic Illness and the Self-rating Depression Scale. Construct validity was assessed using exploratory factor analysis, and internal consistency was tested with Cronbach's α.

RESULTS

The final version Stroke Stigma Scale consists of 16 items. It showed strong positive correlations with both the Stigma Scale for Chronic Illness (ρ = 0.89, P < 0.001) and the Self-rating Depression Scale (ρ = 0.82, P < 0.001). The exploratory factor analysis revealed four components of the Stroke Stigma Scale: internalized stigma, physical impairment, discrimination experience, and social isolation, which were strongly associated with our perceived stroke stigma model. Cronbach's α for the total scale was 0.92, and that of each subscale was 0.77-0.86. The test-retest reliability with intra-class correlation coefficients of the total scale was 0.92 (P < 0.001), and intra-class correlation coefficients of each subscale were 0.74-0.89 (P < 0.001).

CONCLUSIONS

The Stroke Stigma Scale is a reliable and valid measure of perceived stigma in patients with stroke, which may be useful in stigma prevention and stroke rehabilitation.