Dietary protein and protein-rich food in relation to severely depressed mood: A 10 year follow-up of a national cohort

Intestinal gluconeogenesis: A translator of nutritional information needed for glycemic and emotional balance

At the interface between the outside world and the self, the intestine is the first organ receiving nutritional information. One intestinal function, gluconeogenesis, is activated by various nutrients, particularly diets enriched in fiber or protein, and thus results in glucose production in the portal vein in the post-absorptive period. The detection of portal glucose induces a nervous signal controlling the activity of the central nuclei involved in the regulation of metabolism and emotional behavior. Induction of intestinal gluconeogenesis is necessary for the beneficial effects of fiber or protein-enriched diets on metabolism and emotional behavior. Through its ability to translate nutritional information from the diet to the brain's regulatory centers, intestinal gluconeogenesis plays an essential role in maintaining physiological balance.

The cross-sectional association between dietary total, animal, and plant-based protein intake and the prevalence and severity of depressive symptoms in Dutch adults with type 2 diabetes: The Hoorn Diabetes Care System cohort

OBJECTIVE

This study aimed to investigate cross-sectional associations of total, animal, and plant-based protein intake and depressive symptoms in Dutch adults with type 2 diabetes (T2D).

METHODS

We included 1137 individuals with T2D (aged 68.6 ± 9.0) from the Hoorn Diabetes Care System cohort. Energy-adjusted protein intake was assessed using a validated Food Frequency Questionnaire. The nine-item Patient Health Questionnaire (PHQ-9) was used to assess the prevalence of depressive symptoms (PHQ-9 ≥ 10 and/or anti-depressant use) and the severity of depressive symptoms (continuous PHQ-9 score). Associations between total, animal, and plant-based protein (quartiles) with depressive symptoms were assessed using multiple logistic and linear regression.

RESULTS

Highest intake of total, animal, and plant-based protein was not associated with the prevalence of depressive symptoms, compared to lowest intake (e.g., total protein, ORQ4vsQ1:0.75, 95%CI 0.42;1.32). For the severity of depressive symptoms, highest total protein intake was significantly associated with lower PHQ-9 scores (ORQ4vsQ1:0.87, 95%CI 0.75;1.00), compared to lowest intake. Animal protein was not associated with the severity of depressive symptoms (β ∼ 1), while the association for plant-based protein was marginally non-significant (βQ4vsQ1:0.88, 95%CI 0.76;1.02).

CONCLUSION

In individuals with T2D, higher total protein intake was associated with reduced severity of depressive symptoms, but not with the prevalence of depressive symptoms. Further prospective research with a larger sample size is needed to confirm these associations.

The association between plant and animal protein intake with depression, anxiety, and stress

BACKGROUND

Recent evidence suggests that diet composition is a key biological factor related to the development of depressive disorders. The present study was conducted to investigate the animal and plant protein intake and their replacement in association with depression, anxiety, and stress in Iranian adults.

METHOD

In this cross-sectional study, the dietary intake of 7169 subjects were assessed using a validated food frequency questionnaire. The depression, anxiety, and stress Scale - 21 (DASS-21) questionnaire was used to psychological disorders. Logistic regression was used to obtain odds ratios for depression, anxiety, and stress across quintiles of animal and plant protein.

RESULTS

The participants' age range was 20-69 years. Individuals with the highest animal protein consumption had a lower chance for developing depression compared to those with the lowest intakes (OR = 0.73, 95%CI: 0.59-0.90; Ptrend < 0.01). Results also showed a significant association between animal protein intake and anxiety, such that subjects in the highest quintile of animal protein intake had 24% lower odds for anxiety compared to those in the lowest quintile (p < 0.05). We found a significant association between highest quintiles of animal protein intake and a 40% lower risk for stress among female individuals (Ptrend = 0.05). The multivariable-adjusted non-linear analyses also revealed that the replacement of plant protein with animal protein was significantly associated with the likelihood of depression and anxiety (P < 0.05).

CONCLUSION

Animal protein intake might lower the odds of depression and anxiety particularly. Future prospective investigations are proposed to confirm these findings.

Association of macronutrient consumption quality, food source and timing with depression among US adults: A cross-sectional study

BACKGROUND

Growing evidence suggests that meal timing may influence dietary choices and mental health. Thus, this study examined the association between macronutrient consumption quality, food source, meal timing, and depression prevalence in Americans.

METHODS

23,313 National Health and Nutrition Survey participants from 2007 to 2016 were included in this cross-sectional study. Macronutrient intake was calculated for all day, dinner, and breakfast and subtypes into 4 classes. Based on the Patient Health Questionnaire, depression was defined as a 9-item score ≥ 10 on the PHQ-9. The correlation between macronutrients and depression prevalence was estimated with multivariable logistic regression models and isocaloric substitution effects.

RESULTS

Low-quality carbohydrates (OR = 1.54, 95 % CI: 1.11, 2.12) were positively linked to depression compared with the lowest quartile, after adjusting for age and other covariates. In contrast, total high-quality carbohydrate (OR = 0.52, 95 % CI: 0.40, 0.66), total animal protein (OR = 0.60, 95 % CI: 0.45, 0.80), and total vegetable protein (OR = 0.61, 95 % CI: 0.43, 0.85) were negatively associated with depression was negatively associated. Replacing low-quality carbohydrates with high-quality carbohydrates throughout the day reduced the risk of depression by approximately 15 %.

LIMITATIONS

Cross-sectional data.

CONCLUSION

All in all, diet plays a crucial role in the prevention and treatment of depression. Especially in terms of macronutrient intake, high-quality, moderate intake can reduce the risk of depression. However, different subtypes of macronutrient consumption may have different effects on depression, so it becomes crucial to carefully consider the selection and combination of macronutrients.

Protein-enriched and anti-inflammatory dietary patterns, healthy lifestyle index and depressive symptoms: A cross-sectional study of 287,945 adults in China

OBJECTIVES

Depressive symptoms have a considerable negative impact on mental health. This study aimed to understand the relationship between the protein-enriched and anti-inflammatory dietary index scores, modified healthy lifestyle index scores (Modified HLIS), and depressive symptoms.

METHODS

This study used convenience sampling to conduct a single-center cross-sectional survey. From January 1, 2015 to December 31, 2020, a total of 287,945 Chinese adults from a health management center of a general hospital completed an online self-reported health questionnaire, which included demographic characteristics, the Dietary Diversity Scale, the Modified Healthy Lifestyle Index Scores and the Patient Health Questionnaire-9.

RESULTS

The higher anti-inflammatory dietary index scores (POR = 0.87; 95 % CI: 0.86-0.87; p < 0.001), moderate modified healthy lifestyle index scores (POR = 0.76; 95 % CI: 0.75-0.78; p < 0.001) and sufficient modified healthy lifestyle index scores (POR = 0.53; 95 % CI: 0.52-0.54; p < 0.001) were negatively associated with depressive symptoms, while the higher protein-enriched dietary index scores (POR = 1.01; 95 % CI: 1.01-1.02; p < 0.001) was positively correlated with depressive symptoms.

CONCLUSIONS

This study demonstrated that protein-enriched and anti-inflammatory dietary index scores, and multiple healthy lifestyles are associated depressive symptoms in adults.

Association between Western Dietary Patterns, Typical Food Groups, and Behavioral Health Disorders: An Updated Systematic Review and Meta-Analysis of Observational Studies

Western dietary patterns (WDP) and typical food groups may play a major role in the risk of behavioral health disorders. Nevertheless, the relationships between WDP, common food categories, and mental health disorders lack consistency and remain incompletely understood in relation to potential mechanisms. Therefore, the objective of the present study was conducted to synthesize available evidence linking WDP and typical food groups to these outcomes. Web of Science, PubMed, EMBASE, and MEDLINE were searched up to August 2023. Random effect meta-analyses were performed to obtain pooled odds ratio and the relative risk for the prevalence of outcomes and the incidence of outcomes, respectively. A total of 54 articles were included. WDP was associated with increased risk of both depression (1.19; 95% CI: 1.06-1.32) and depressive symptoms (1.20; 95% CI: 1.08-1.34). Except for high-fat dairy products, food groups are associated with an increased risk of anxiety, depression, and depressive symptoms. This review presents evidence to further understand the relationship between WDP, typical food groups, and the incidence of behavioral health disorders, and more randomized controlled trials and cohort studies are urgently required to confirm these findings and elucidate potential mechanisms.

National Nutrition Surveys Applying Dietary Records or 24-h Dietary Recalls with Questionnaires: A Scoping Review

Development of an accurate and efficient dietary method is required for national nutrition surveys. Some countries conduct dietary surveys and combine 24-h dietary records or 24-h dietary recalls with dietary questionnaires. This scoping review aimed to summarize studies that used results from national surveys that combined detailed dietary surveys (dietary records or 24-h dietary recall) and dietary questionnaires and identify the purpose of combining the two methods. The PubMed database and manual searches were used for the literature review. We extracted 58 articles from 16 national nutrition surveys from 14 countries. Most studies used 24-h dietary recall for detailed dietary surveys and the food frequency questionnaire (FFQ) or food propensity questionnaire (FPQ) for questionnaire surveys. Among 37 studies from eight countries, the purpose of combining the two dietary survey methods was to estimate energy and nutrient intakes from detailed dietary surveys and habitual food intake from questionnaires. These findings are useful as a reference when introducing new dietary survey methods in future national nutrition surveys.

Gut Microbiota Signatures Are Associated With Psychopathological Profiles in Patients With Ulcerative Colitis: Results From an Italian Tertiary IBD Center

BACKGROUND

Several patients with ulcerative colitis (UC) suffer from psychiatric disorders, such as major depressive disorder, anxiety, or bipolar disorder, and show specific personality traits. Despite this, there are few data about personality profiles' characterization in UC patients and about correlation of their psychopathological profile with their intestinal microbiota.The aim of our study is to analyze the psychopathological and personality profile of UC patients and correlate it with specific signatures of their gut microbiota.

METHODS

This is a prospective interventional longitudinal cohort study. We enrolled consecutive patients affected by UC attending to the IBD Unit of Center for Digestive Disease of "A. Gemelli" IRCCS Hospital in Rome and a group of healthy subjects, matched for specific characteristics. Each patient was evaluated by a gastroenterologist and a psychiatrist. Moreover, all participants underwent psychological tests and a collection of stool samples.

RESULTS

We recruited 39 UC patients and 37 healthy subjects. Most patients showed high level of alexithymia, anxiety symptoms, depressive symptoms, as well as neuroticism and hypochondria, with obsessive-compulsive features at the behavioral level, which significantly impaired their quality of life and abilities at work. Gut microbiota analysis in UC patients demonstrated an increase in actinobacteria, Proteobacteria and Saccharibacteria (TM7), with a reduction in verrucomicrobia, euryarchaeota and tenericutes.

CONCLUSIONS

Our study confirmed the presence of high levels of psycho-emotional distress in UC patients, alongside alterations of the intestinal microbiota, and highlighted some families and genera of bacteria (Enterobacteriaceae, Streptococcus, Veillonella, Klebsiella, and Clostridiaceae) as potential markers of an altered gut-brain axis in these patients.

Suboptimal dietary quality is associated with mental symptoms among adults aged 40 years and over in China: A population-based cross-sectional study

BACKGROUND

The previous studies an association between dietary patterns and psychiatric symptoms. However, few studies have examined the association of quality of dietary patterns and anxiety, depressive symptoms in the Chinese population.

METHODS

Between 2017 and 2019, a population-based, cross-sectional survey was carried out in China. Uniformed questionnaires collected the demographic characteristics and food data. The dietary quality of the adults was evaluated using the revised Diet Balance Index 2016 (DBI-16). We measured anxiety and depression symptoms using the the Generalized Anxiety Disorder (GAD)-7 and Patient Health Questionnaire (PHQ)-9.

RESULTS

A total of 73,737 participants were recruited during the survey period. 17.6 % and 13.7 % of residents suffer from anxiety and depression symptoms, respectively. The DBI-16 indicates that participants with anxiety or depression symptoms had higher scores of low bound score (LBS, refers to inadequate food intake) and dietary quality distance (DQD, refers to unbalanced food intake) than those without anxiety or depression. The logistic regression models showed that high levels of LBS and DQD problems were more strongly associated with anxiety (LBS:OR = 1.20, DQD:OR = 1.30) and depressive symptoms (LBS:OR = 1.21, DQD:OR = 1.44). On the contrary, higher bound score (HBS, refers to excessive food intake) was significantly negatively correlated with symptoms of anxiety and depression. Moreover, each increase in the food group was associated with 4 % lower odds of anxiety and 6 % lower odds of depression symptoms.

LIMITATIONS

Cross-sectional design and self-reporting of psychological symptoms and dietary information limit the generalizability of the results.

CONCLUSION

The dietary quality of adults aged 40 years and over in China is suboptimal, with excessive and inadequate food intake simultaneously. Dietary imbalance, and low dietary diversity may be related to anxiety and depressive symptoms.

Influence of Weight-Control Attempts as Based on Self-Perception of Macronutrient Intake Among Young Females and Its Association with Mood Disorder

Background

There are a few studies on the association between macronutrients and mood, but none on weight control based on self-perception of specific macronutrients and mood.

Objective

To assess the association between anxiety and depression levels and weight-control attempts among young females based on self-perception of diet that impacts weight by limiting or boosting a certain macronutrient.

Methods

A cross-sectional survey conducted on young females (n=302) with an age range of 19 to 29. Dietary intake was measured using the Food frequency questionnaire (FFQ) and 24h-dietary recall. Anxiety and depression were measured using the Hospital Anxiety and Depression Scale (HADS) questionnaire.

Results

Analysis of the data showed a significant and inverse association of macronutrients - carbohydrates (OR 0.86; 95% CI 0.77-0.95; p < 0.01), protein (OR 0.87; 95% CI 0.78-0.97; p < 0.05), and fat (OR 0.79; 95% CI 0.63-0.99; p < 0.05) - with the odds of abnormal anxiety was noted. In addition, lower omega-3 intake was significantly associated with abnormal anxiety score (OR 0.85; 95% CI 0.76-0.97; p < 0.05) and abnormal depression score (OR 0.31; 95% CI 0.14-0.68; p < 0.01). Increased calorie intake is associated with an increased risk of anxiety scores.

Conclusion

This preliminary study found the importance of monitoring dietary intake, especially macronutrients, among the young population to screen for any onset of mood symptoms, especially for those who are following a specific diet without any supervision. Young people should be aware of the importance of following a balanced diet and seek dietitians' consultation.

The associations of dietary patterns with depressive and anxiety symptoms: a prospective study

BACKGROUND

Diet is increasingly recognized as an important risk factor for mental health. However, evidence regarding the association between diet pattern and depressive and anxiety symptoms is limited. We aimed to investigate the associations of dietary patterns characterized by a set of nutrients of interest with depressive and anxiety symptoms.

METHODS

The analyses included a total of 126,819 participants in the UK Biobank who had completed at least two dietary questionnaires. Dietary data were obtained through 24-h dietary assessment at baseline between 2006 and 2010 and four rounds of online follow-ups between 2011 and 2012. Reduced rank regression was applied to derive dietary patterns (DPs) explaining variability in energy density, free sugars, saturated fat, and fiber intakes. Depressive and anxiety symptoms were measured by the Patient Health Questionnaire-9 and General Anxiety Disorder-7 between 2016 and 2017, respectively. Logistic regression models were performed to investigate the associations between dietary patterns and depressive and anxiety symptoms.

RESULTS

During a mean follow-up of 7.6 years, 2746 cases of depressive symptoms and 2202 cases of anxiety symptoms were recorded. Three major DPs were derived, explaining 74% of the variation in nutrients hypothesized to be related to depressive and anxiety symptoms. DP1 was characterized by high intakes of chocolate, confectionery, butter, and low vegetable/fruit intakes. Compared to the lowest quintile of DP1, the odds ratio (95% confidence interval) of depressive symptoms for Q2-Q5 was 0.82 (0.72-0.93), 0.86 (0.76-0.98), 1.02 (0.90-1.15), and 1.17 (1.03-1.32), respectively. Compared to the lowest quintile of DP1, the odds ratio (95% CI) of anxiety symptoms for Q2-Q5 was 0.84 (0.73-0.97), 0.91 (0.79-1.05), 1.01 (0.88-1.15), and 1.18 (1.03-1.35), respectively. DP2 featured high intakes of sugar-sweetened beverages, added sugars, and low intakes of butter/cheese but showed no significant links to depressive or anxiety symptoms. DP3 was characterized by high butter and milk desserts and low alcohol/bread intakes. Compared to the lowest quintile of DP3, the odds ratio (95% CI) of depressive symptoms for Q2-Q5 was 0.90 (0.79-1.01), 1.00 (0.88-1.13), 1.06 (0.94-1.20), and 1.17 (1.03-1.32), respectively. Compared to the lowest quintile of DP3, the odds ratio (95% CI) of anxiety symptoms for Q2-Q5 was 0.90 (0.78-1.04), 1.05 (0.91-1.20), 1.02 (0.89-1.17), and 1.21 (1.05-1.38), respectively.

CONCLUSIONS

A DP characterized by high intakes of chocolate and confectionery, butter, high-fat cheese, added sugars, along with low intakes of fresh fruit and vegetables, is associated with a higher risk of depressive and anxiety symptoms.

Dietary protein intake affects the association between urinary iodine and clinically relevant depression: Evidence from NHANES 2007-2018

Both iodine concentration and protein intake are important nutritional factors that may influence the development of depressive symptoms. However, there are no studies on the effect of protein intake on the relationship between iodine concentration and the risk of depression. The study aimed to explore the relationship between iodine and the risk of clinically relevant depression (CRD) according to protein intake. This study analyzed the adults (≥18 years) who participated in the 2007-2018 National Health and Nutrition Cross-sectional Survey (N = 10,462). CRD was assessed using the Patient Health Questionnaire (PHQ-9). Protein intake was assessed using two 24-h dietary recalls and urinary iodine concentration (UIC) was measured using inductively coupled plasma dynamic response cell mass spectrometry. Weighted multivariate logistic regression and restrictive cubic splines were performed to assess the relationship between UIC and CRD according to protein category (low protein intake <0.8 g/kg/day; high protein intake: ≥0.8 g/kg/day). After controlling for sociodemographic, behavioral, chronic diseases, and dietary factors, a positive correlation was observed between UIC (log10) and CRD (OR: 1.36, 95% CI: 1.026, 1.795). Low UIC (<100 μg/L) was associated with a lower prevalence of CRD (OR: 0.73, 95% CI: 0.533, 0.995) in high protein intake individuals, whereas this relationship did not exist in those with low protein intake. Moreover, restrictive cubic splines confirmed a near L-shaped relationship between UIC and CRD in the low-protein group (nonlinear p = .042) and a linear relationship between them in the high-protein group (nonlinear p = .392). This study illustrates that protein intake affects the relationship between UIC and CRD. Combining lower UIC and high protein intake may help reduce the prevalence of CRD, which would have significant implications for managing patients with depressive CRD in the clinical setting.

Association between dietary habits and the risk of migraine: a Mendelian randomization study

Objective

The important contribution of dietary triggers to migraine pathogenesis has been recognized. However, the potential causal roles of many dietary habits on the risk of migraine in the whole population are still under debate. The objective of this study was to determine the potential causal association between dietary habits and the risk of migraine (and its subtypes) development, as well as the possible mediator roles of migraine risk factors.

Methods

Based on summary statistics from large-scale genome-wide association studies, we conducted two-sample Mendelian randomization (MR) and bidirectional MR to investigate the potential causal associations between 83 dietary habits and migraine and its subtypes, and network MR was performed to explore the possible mediator roles of 8 migraine risk factors.

Results

After correcting for multiple testing, we found evidence for associations of genetically predicted coffee, cheese, oily fish, alcohol (red wine), raw vegetables, muesli, and wholemeal/wholegrain bread intake with decreased risk of migraine, those odds ratios ranged from 0.78 (95% CI: 0.63-0.95) for overall cheese intake to 0.61 (95% CI: 0.47-0.80) for drinks usually with meals among current drinkers (yes + it varies vs. no); while white bread, cornflakes/frosties, and poultry intake were positively associated with the risk of migraine. Additionally, genetic liability to white bread, wholemeal/wholegrain bread, muesli, alcohol (red wine), cheese, and oily fish intake were associated with a higher risk of insomnia and (or) major depression disorder (MDD), each of them may act as a mediator in the pathway from several dietary habits to migraine. Finally, we found evidence of a negative association between genetically predicted migraine and drinking types, and positive association between migraine and cups of tea per day.

Significance

Our study provides evidence about association between dietary habits and the risk of migraine and demonstrates that some associations are partly mediated through one or both insomnia and MDD. These results provide new insights for further nutritional interventions for migraine prevention.

Appropriate Macronutrients or Mineral Elements Are Beneficial to Improve Depression and Reduce the Risk of Depression

Depression is a common mental disorder that seriously affects the quality of life and leads to an increasing global suicide rate. Macro, micro, and trace elements are the main components that maintain normal physiological functions of the brain. Depression is manifested in abnormal brain functions, which are considered to be tightly related to the imbalance of elements. Elements associated with depression include glucose, fatty acids, amino acids, and mineral elements such as lithium, zinc, magnesium, copper, iron, and selenium. To explore the relationship between these elements and depression, the main literature in the last decade was mainly searched and summarized on PubMed, Google Scholar, Scopus, Web of Science, and other electronic databases with the keywords "depression, sugar, fat, protein, lithium, zinc, magnesium, copper, iron, and selenium". These elements aggravate or alleviate depression by regulating a series of physiological processes, including the transmission of neural signals, inflammation, oxidative stress, neurogenesis, and synaptic plasticity, which thus affect the expression or activity of physiological components such as neurotransmitters, neurotrophic factors, receptors, cytokines, and ion-binding proteins in the body. For example, excessive fat intake can lead to depression, with possible mechanisms including inflammation, increased oxidative stress, reduced synaptic plasticity, and decreased expression of 5-Hydroxytryptamine (5-HT), Brain Derived Neurotrophic Factor (BDNF), Postsynaptic density protein 95(PSD-95), etc. Supplementing mineral elements, such as selenium, zinc, magnesium, or lithium as a psychotropic medication is mostly used as an auxiliary method to improve depression with other antidepressants. In general, appropriate nutritional elements are essential to treat depression and prevent the risk of depression.

Intestinal gluconeogenesis: metabolic benefits make sense in the light of evolution

The intestine, like the liver and kidney, in various vertebrates and humans is able to carry out gluconeogenesis and release glucose into the blood. In the fed post-absorptive state, intestinal glucose is sensed by the gastrointestinal nervous system. The latter initiates a signal to the brain regions controlling energy homeostasis and stress-related behaviour. Intestinal gluconeogenesis (IGN) is activated by several complementary mechanisms, in particular nutritional situations (for example, when food is enriched in protein or fermentable fibre and after gastric bypass surgery in obesity). In these situations, IGN has several metabolic and behavioural benefits. As IGN is activated by nutrients capable of fuelling systemic gluconeogenesis, IGN could be a signal to the brain that food previously ingested is suitable for maintaining plasma glucose for a while. This process might account for the benefits observed. Finally, in this Perspective, we discuss how the benefits of IGN in fasting and fed states could explain why IGN emerged and was maintained in vertebrates by natural selection.

Dietary factors, risk of developing depression, and severity of its symptoms in older adults-A narrative review of current knowledge

Depression is one of the most common diseases in the older population. Difficulties in recognizing its etiology and recurrence make depression a major challenge for health care professionals. The risk of developing depression is influenced by many factors, including lifestyle and diet. Research studies have shown a relationship between the consumption of specific macro- and microelements and depression. However, so far, no nutritional recommendations on how to reduce the risk of the disease and its relapses in older adults have been developed. This review outlines research results of conducted studies and focuses on both basic and potentially promising elements of diet, such as proteins, carbohydrates, fats, dietary fiber, vitamins (D, E, C, and B), and microelements such as magnesium, zinc, selenium, or iron.

Macronutrients and the state of happiness and mood in undergraduate youth of a military training course

BACKGROUND AND AIMS

Previous studies have reported a high prevalence of mental disorders among military organizations. Depression and anxiety are among the most important mental disorders, and depression, suicidal ideation, and violence have been found to be negatively associated with happiness and social support. Therefore, improving mood and increasing happiness can reduce the prevalence of mental disorders in military centers. Diet can improve happiness through specific molecular mechanisms and change our mood by affecting the chemical composition of the brain. Therefore, the present study examined the relationship between the quality and quantity of macronutrients in soldiers' diets with their mood and happiness.

METHODS

In the current cross-sectional study, 300 healthy soldiers were selected. Food intake data was collected using 168-item semi-quantitative food frequency questionnaire during the last year of their military training 2-year period. Then, we calculated the quality and quantity of macronutrients. Mood was assessed using the Profile of Mood States (POMS) questionnaire and happiness with the Oxford Happiness Questionnaire (OHQ).

RESULTS

The mean ± standard deviation of participants' age was 23.70 ± 1.76 years. A significant relationship was observed between mood score and carbohydrate quantity (OR: 0.32, 95% CI: 0.12-0.88, P-value for trend = 0.03). This suggests that increasing carbohydrate intake improved the participants' mood. No association was found between mood score with protein quantity (OR: 2.15, 95% CI: 0.80-5.75; P-value for trend = 0.12), and gram of fat intake (OR: 1.95, 95% CI: 0.74-5.13; P-value for trend = 0.15). None of the indicators related to macronutrient quality were significantly associated with happiness and mood scores in young soldiers (P ≥ 0.05).

CONCLUSIONS

Findings presented in this study showed that increased carbohydrate intake was significantly associated with better mood. However, mood is not related to the amount of proteins and fats and none of the parameters of macronutrient quality. Also, there was no significant relationship between the quantity and quality of macronutrients with happiness score.

Associations between total dairy, high-fat dairy and low-fat dairy intake, and depressive symptoms: findings from a population-based cross-sectional study

PURPOSE

Evidence on the association between dairy intake and depression is conflicting. Given numerous dietary guidelines recommend the consumption of low-fat dairy products, this study examined associations between total dairy, high-fat dairy, and low-fat dairy intake and the prevalence of elevated depressive symptoms. Associations between dairy products, which differed in both fat content and fermentation status, and depressive symptoms were also explored.

METHODS

This cross-sectional study included 1600 Finnish adults (mean age 63 ± 6 years; 51% female) recruited as part of the Kuopio Ischaemic Heart Disease Risk Factor Study. Dairy intake was assessed using 4-day food records. Elevated depressive symptoms were defined as having a score ≥ 5 on the Diagnostic and Statistical Manual of Mental Disorders-III Depression Scale, and/or regularly using one or more prescription drugs for depressive symptoms.

RESULTS

In total, 166 participants (10.4%) reported having elevated depressive symptoms. Using multivariate logistic regression models, intake in the highest tertile of high-fat dairy products (OR 0.64, 95% CI 0.41-0.998, p trend = 0.04) and high-fat non-fermented dairy products (OR 0.60, 95% CI 0.39-0.92, p trend = 0.02) were associated with reduced odds for having elevated depressive symptoms. Whereas no significant association was observed between intake of total dairy, low-fat dairy, or other dairy products, and depressive symptoms.

CONCLUSION

Higher intake of high-fat dairy and high-fat non-fermented dairy products were associated with reduced odds for having elevated depressive symptoms in middle-aged and older Finnish adults. Given the high global consumption of dairy products, and widespread burden of depression, longitudinal studies that seek to corroborate these findings are required.

Anti-Inflammatory Dietary Diversity and Depressive Symptoms among Older Adults: A Nationwide Cross-Sectional Analysis

The purpose of this study was to associate the anti-inflammatory dietary diversity and depressive symptoms among a nationwide sample of Chinese older adults. We used data from the 2018 wave of Chinese longitudinal healthy longevity survey (CLHLS). We assessed depressive symptoms using the 10 items of the center for epidemiologic studies depression scale (CES-D-10). Based on the dietary diversity index (DDI) generated by previous studies, we construct two novel indicators: the protein-enriched dietary diversity index diet (PEDDI) and the anti-inflammatory dietary diversity index diet (AIDDI). We used multivariate logistic models to evaluate the associations of DDI, PEDDI, and AIDDI with depressive symptoms, statistically adjusted for a range of potential confounders. A total of 12,192 participants (mean age 83.6 years) were included in the analysis. We found that participants with a higher score of DDI (OR = 0.91, 95% CI: 0.89-0.92) and PEDDI (OR = 0.91, 95% CI: 0.88-0.93) showed lower odds of having depressive symptoms, while the association between AIDDI and depressive symptoms was more marked (OR = 0.80, 95% CI: 0.78-0.83). The associations remained in subgroup analyses and sensitivity analyses. The results indicate that intaking diversified diet, particularly anti-inflammatory foods, may be associated with a lower risk of depressive symptoms. The findings of this study, if confirmed as causal, provide evidence that an intervention of adopting an anti-inflammatory diversified diet may reduce the burden of depression among older adults.

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.

The Problem of Malnutrition Associated with Major Depressive Disorder from a Sex-Gender Perspective

Major depressive disorder (MDD) is an incapacitating condition characterized by loss of interest, anhedonia and low mood, which affects almost 4% of people worldwide. With rising prevalence, it is considered a public health issue that affects economic productivity and heavily increases health costs alone or as a comorbidity for other pandemic non-communicable diseases (such as obesity, cardiovascular disease, diabetes, inflammatory bowel diseases, etc.). What is even more noteworthy is the double number of women suffering from MDD compared to men. In fact, this sex-related ratio has been contemplated since men and women have different sexual hormone oscillations, where women meet significant changes depending on the age range and moment of life (menstruation, premenstruation, pregnancy, postpartum, menopause…), which seem to be associated with susceptibility to depressive symptoms. For instance, a decreased estrogen level promotes decreased activation of serotonin transporters. Nevertheless, sexual hormones are not the only triggers that alter neurotransmission of monoamines and other neuropeptides. Actually, different dietary habits and/or nutritional requirements for specific moments of life severely affect MDD pathophysiology in women. In this context, the present review aims to descriptively collect information regarding the role of malnutrition in MDD onset and course, focusing on female patient and especially macro- and micronutrient deficiencies (amino acids, ω3 polyunsaturated fatty acids (ω3 PUFAs), folate, vitamin B12, vitamin D, minerals…), besides providing evidence for future nutritional intervention programs with a sex-gender perspective that hopefully improves mental health and quality of life in women.

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 Moo'D Study: protocol for a randomised controlled trial of A2 beta-casein only versus conventional dairy products in women with low mood

Background

Beta-casein is a major protein in cow’s milk, of which A1 and A2 are the most frequent variants. Recent evidence implicates A1 beta-casein consumption in mechanisms that are of potential importance to mental health, yet its possible effects on psychological endpoints remains unknown. The primary aim of the study is to evaluate the comparative effects of consumption of dairy products containing A2 beta-casein versus conventional dairy (i.e. containing both A1 and A2 beta-casein) on symptoms of psychological distress in women with low mood.

Methods

‘The Moo’D Study’ is a 16-week, superiority, 1:1 parallel group, triple-blinded, randomised controlled trial. Ninety women with low mood (Patient Health Questionnaire score ≥ 5) will be randomised to consume either A2 beta-casein only or conventional dairy products. The primary outcome, symptoms of psychological distress, will be measured by the 21-item Depression, Anxiety and Stress Scale. Secondary outcomes will include symptoms of depression, anxiety and stress, severity of low mood, cognition, gut microbiota composition, gut symptomatology, markers of immune function, gut inflammation, systemic metabolites, endothelial integrity and oxidative stress, body composition, perceived wellbeing, sleep, quality of life, resource use and cost-effectiveness.

Discussion

This study will advance our understanding of the possible impact of milk proteins on psychological distress in women as well as elucidate mechanisms underpinning any association. Given dairy products form a substantial component of traditional and Western diets, the implications of these findings are likely to be of clinical and public health importance.

Trial registration

The trial protocol has been prospectively registered with the Australia and New Zealand Clinical Trials Registry, ACTRN12618002023235. Registered on 17 December 2018.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-021-05812-6.

A Differential Threshold of Breakfast, Caffeine and Food Groups May Be Impacting Mental Well-Being in Young Adults: The Mediation Effect of Exercise

Diet and exercise are known to influence mental health. However, the interaction between diet, dietary practices, and exercise and its impact on the mood of young adults (YA) is poorly understood. YA are inherently at risk for mental distress. They tend to consume a low-quality diet and are generally active. The purpose of the study was to assess these relationships through validating causal loop diagrams (CLD) that describe these connections by using a system dynamic (SD) modeling methodology. Adults 18-29 years were invited to complete the Food-Mood questionnaire. The anonymous questionnaire link was distributed to several institutional listservs and via several social media platforms targeting young adults. A multi-level analysis, including machine learning techniques, was used to assess these relationships. The key findings were then built into gender based CLD, which suggest that a differential repertoire may be needed to optimize diet quality, exercise, and mental well-being. Additionally, a potential net threshold for dietary factors and exercise may be needed to achieve mental well-being in young adults. Moreover, our findings suggest that exercise may boost the enhancing effect of food groups on mental well-being and may lessen the negative impact of dietary impediments of mental well-being.

Nutrition and behavioral health disorders: depression and anxiety

Suboptimal nutrition has been implicated in the underlying pathology of behavioral health disorders and may impede treatment and recovery. Thus, optimizing nutritional status should be a treatment for these disorders and is likely important for prevention. The purpose of this narrative review is to describe the global burden and features of depression and anxiety, and summarize recent evidence regarding the role of diet and nutrition in the prevention and management of depression and anxiety. Current evidence suggests that healthy eating patterns that meet food-based dietary recommendations and nutrient requirements may assist in the prevention and treatment of depression and anxiety. Randomized controlled trials are needed to better understand how diet and nutrition-related biological mechanisms affect behavioral health disorders, to assist with the development of effective evidence-based nutrition interventions, to reduce the impact of these disorders, and promote well-being for affected individuals.

The relation between low carbohydrate diet score and psychological disorders among Iranian adults

BACKGROUND

Since evidence regarding to low carbohydrate diet (LCD) and psychiatric disorders is little and controversial, this study aimed to assess relation between LCD score and psychological disorders including depression, anxiety, and stress among a large representative sample of Iranian adult population in Yazd city, Iran.

METHODS

This cross-sectional analysis was conducted on data of 7165 persons who participated in the recruitment phase of Yazd Health Study (YaHS) and Taghzieh Mardom-e-Yazd (TAMIZ) study. Dietary intakes were evaluated by a validated semi-quantitative food frequency questionnaire. LCD score was calculated for each person according to summing up assigned scores to deciles of percentages of energy from macronutrients. Assessment of psychological disorders was also conducted by the validated Iranian version of depression, anxiety and stress scale questionnaire (DASS 21). Eventually, association between adherence to LCD and psychological disorders was evaluated via logistic regression.

RESULTS

After adjusting the confounders, women in the third quartile of LCD score might had 38% lower chance of depression versus those in the first quartile (odds ratio (OR) = 0.62, confidence interval (CI) = 0.42-0.93). However, no significant relationship was observed for other psychological disorders.

CONCLUSIONS

More adherences to LCD might be associated with lower chance of depression only among women. Further studies special prospective studies are required to validate these results.

Dietary Fibers and Proteins Modulate Behavior via the Activation of Intestinal Gluconeogenesis

INTRODUCTION

Several studies have suggested that diet, especially the one enriched in microbiota-fermented fibers or fat, regulates behavior. The underlying mechanisms are currently unknown. We previously reported that certain macronutrients (fermentable fiber and protein) regulate energy homeostasis via the activation of intestinal gluconeogenesis (IGN), which generates a neural signal to the brain. We hypothesized that these nutriments might control behavior using the same gut-brain circuit.

METHODS

Wild-type and IGN-deficient mice were fed chow or diets enriched in protein or fiber. Changes in their behavior were assessed using suited tests. Hippocampal neurogenesis, extracellular levels of serotonin, and protein expression levels were assessed by immunofluorescence, in vivo dialysis, and Western blotting, respectively. IGN was rescued by infusing glucose into the portal vein of IGN-deficient mice.

RESULTS

We show here that both fiber- and protein-enriched diets exert beneficial actions on anxiety-like and depressive-like behaviors. These benefits do not occur in mice lacking IGN. Consistently, IGN-deficient mice display hallmarks of depressive-like disorders, including decreased hippocampal neurogenesis, basal hyperactivity, and deregulation of the hypothalamic-pituitary-adrenal axis, which are associated with increased expression of the precursor of corticotropin-releasing hormone in the hypothalamus and decreased expression of the glucocorticoid receptor in the hippocampus. These neurobiological alterations are corrected by portal glucose infusion mimicking IGN.

CONCLUSION

IGN translates nutritional information, allowing the brain to finely coordinate energy metabolism and behavior.

Food and Mood: the Corresponsive Effect

PURPOSE OF REVIEW

The question whether food choice and eating behavior influence the mood or are influenced by the mood has been inquisitive to scientists and researchers. The purpose of this review is to support or refuse the argument that mood is affected by food or vice versa.

RECENT FINDINGS

The association between food and mood has been comprehensively elucidated in this review based on several studies that include participants from different ages, cultural backgrounds, and health status. The correlation among food, mood, and diseases such as diabetes mellitus, obesity, and depression was thoroughly investigated. The effect of different foods and nutrients on the mood was further explained. It is concluded that the mood significantly affects food intake and food choices. On the other hand, food also influences the mood, which affects the diseases either positively or negatively. Appropriate food choices play a significant role in mood enhancement. Advertisement is another crucial factor that negatively affects food choices and mood and contributes to many diseases. Understanding the interaction between food and mood can help to prevent or alleviate undesired health issues.

Association Between Macronutrients Intake and Depression in the United States and South Korea

Although the risk for depression appears to be related to daily dietary habits, how the proportion of major macronutrients affects the occurrence of depression remains largely unknown. This study aims to estimate the association between macronutrients (i.e., carbohydrate, protein, fat) and depression through national survey datasets from the United States and South Korea. Association between the prevalence of depression and each macronutrient was measured from 60,935 participants from the National Health and Nutrition Examination Survey (NHANES) and 15,700 participants from the South Korea NHANES (K-NHANES) databases. When the proportion of calories intake by protein increased by 10%, the prevalence of depression was significantly reduced both in the United States [Odds Ratio, OR (95% CI), 0.621 (0.530-0.728)] and South Korea [0.703 (0.397-0.994)]. An association between carbohydrate intake and the prevalence of depression was seen in the United States [1.194 (1.116-1.277)], but not in South Korea. Fat intake was not significantly associated with depression in either country. Subsequent analysis showed that the low protein intake groups had significantly higher risk for depression than the normal protein intake groups in both the United States [1.648 (1.179-2.304)] and South Korea [3.169 (1.598-6.286)]. In the daily diet of macronutrients, the proportion of protein intake is significantly associated with the prevalence of depression. These associations were more prominent in adults with insufficient protein intake, and the pattern of association between macronutrients and depression in Asian American and South Korean populations were similar. Our findings suggest that the proportion of macronutrients intake in everyday life may be related to the occurrence of depression.

Association between dietary protein intake and the risk of depressive symptoms in adults

Depression is an important public health problem. The aim of the study is to explore the associations of total protein intake and protein sources with the risk of depressive symptoms. This cross-sectional study used data from the National Health and Nutrition Examination Survey for the years 2007–2014. Dietary protein intake was obtained from two 24-h dietary recall interviews. Depressive symptoms were assessed by a nine-item Patient Health Questionnaire. Logistic regression models and restricted cubic spline models were used to estimate the associations of total protein intake (g/kg per d) and protein sources with the risk of depressive symptoms. A total of 17 845 individuals aged 18 years and older were included in this study. Total protein intake was inversely associated with the risk of depressive symptoms. The full-adjusted OR of depressive symptoms was 0·34 (95 % CI 0·17, 0·68) for quartile (Q) 4 v. Q1 of total protein intake. For protein intake from milk and milk products, the association with depressive symptoms was significant both for Q2 v. Q1 (OR 0·61; 95 % CI 0·41, 0·93) and Q3 v. Q1 (OR 0·37; 95 % CI 0·24, 0·59) in the full-adjusted model. In the dose–response analysis, the shape of the associations of total protein intake and protein intake from milk and milk products with the risk of depressive symptoms was approximately L-shaped and U-shaped, respectively. The present study demonstrated that total protein intake and protein intake from milk and milk products might reduce the risk of depressive symptoms in US adults.

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.

Adherence to low carbohydrate diet and prevalence of psychological disorders in adults

Background

Although individual macronutrients were studied in relation to mental health, no information exist about the association between adherence to low carbohydrate diet and psychological disorders. This study was conducted to investigate the association between adherence to a low carbohydrate diet and prevalence of psychological disorders among Iranian adults.

Methods

In this cross-sectional study on 3362 adult men and women, dietary intakes were examined by the use of a validated semi-quantitative food frequency questionnaire. Low carbohydrate diet (LCD) score was computed for each participant based on deciles of percentages of energy from macronutrients. Then the scores of carbohydrate, protein and fat intake for each participant were summed up to achieve the overall LCD score, which ranged from 3 (highest carbohydrate intake and lowest fat and protein intakes) to 30 (lowest carbohydrate intake and highest fat and protein intakes). Anxiety, depression, and psychological distress were assessed by validated Iranian versions of the Hospital Anxiety and Depression Scale and General Health Questionnaire-12.

Results

Prevalence of depression, anxiety and psychological distress in the whole population were 28.0, 13.3 and 22.6%, respectively. No significant differences were observed in the distribution of depression, anxiety and psychological distress across different quartiles of LCD score. After controlling for potential confounders, no significant association was seen between LCD score and prevalence of depression (OR for the highest vs. the lowest quartile of LCD score: (1.15; 95% CI: 0.93, 1.39). Consumption of LCD was not also associated with increased risk of anxiety (0.82; 95% CI: 0.59, 1.14) and psychological distress (0.92; 95% CI: 0.72, 1.16). These associations did not alter when the analyses were done stratified by gender or BMI status.

Conclusion

Adherence to the low carbohydrate diet, which contains high amount of fat and proteins but low amounts of carbohydrates, was not associated with increased odds of psychological disorders including depression, anxiety and psychological distress. Given the cross-sectional nature of the study which cannot reflect causal relationships, longitudinal studies, focusing on types of macronutrients, are required to clarify this association.

Body-weight and psychological well-being in the UK general population

Background

While the consequences of body weight for physical health are well explored, the evidence for psychological well-being is less straightforward. An instrumental variable approach is used to address the endogenous relationship between body weight and well-being in the UK general population.

Methods

Data from the Health Survey for England (2003, 2004 and 2006) are used to fit linear and ordered probit instrument variable models for a sample of 13 862 individuals, with frequent white meat consumption instrumenting for body-weight. Non-linearities in the relationship, robustness to weak instruments and relaxation of strict exogeneity assumption are further examined.

Results

Accounting for endogeneity and conditional on health a protective effect on well-being is observed. A unit increase in body mass index (BMI) improves General Health Questionnaire (GHQ) by 0.17 (95% CI: 0.02-0.31) points and reduces the probability of reporting very low GHQ by 2.5% (95% CI: 0.01-0.05). Empirical testing showed that the instrument performs well, with increased meat consumption adding 0.58 points (95% CI: 0.42-0.74) to ones' BMI.

Conclusions

We present support for the jolly-fat hypothesis, however, caution is recommended in drawing inferences. Further research needs to resolve the mixed findings in the literature.

Dietary acid load in relation to depression and anxiety in adults

BACKGROUND

No previous study has examined the association of dietary acid load (DAL) with depression and anxiety in adults. The present study aimed to investigate the association between DAL and the risk of depression and anxiety in Iranian adults.

METHODS

In total, 4378 non-academic healthy personnel (1909 men and 2469 women) were included in this cross-sectional study. A validated detailed food frequency questionnaire (FFQ) was used to assess dietary intakes of participants. DAL was estimated using the protein to potassium ratio (Pro:K). Depression and anxiety were screened using an Iranian validated Hospital Anxiety and Depression Scale questionnaire.

RESULTS

Participants with the highest DAL had a higher risk of depression compared to those in the lowest category [odds ratio (OR) = 1.57; 95% confidence interval (CI) = 1.27-1.95, P_trend  < 0.001), which remained unchanged after controlling for probable confounders, such that those in the top category of DAL had a 100% higher risk of having depression than those in the bottom category (OR = 2.00; 95% CI = 1.52-2.64). In addition, a significant positive association was seen between DAL and anxiety in a crude model (OR = 1.35; 95% CI = 1.02-1.78, P_trend  = 0.01) and even after adjustment for a wide range of confounders, such that participants in the top category of DAL had a 92% greater risk of anxiety than those in the bottom category (OR = 1.92; 95% CI = 1.35-2.74, P_trend  < 0.001).

CONCLUSIONS

In the present study, we found a significant direct association between DAL and the risk of depression, as well as anxiety. Further studies, in particular prospective cohorts are required to confirm these findings.

Breakfast consumption and the risk of depressive symptoms: The Furukawa Nutrition and Health Study

Breakfast consumption has been suggested to influence mood, but prospective evidence on this issue is limited. We prospectively investigated the association between the frequency of breakfast consumption and the risk of depressive symptoms in Japanese employees. Participants were 716 employees aged 19-68 years who were free from depressive symptoms and mental disorders at baseline and who attended the 3-year follow-up survey. Depressive symptoms were assessed using the Center for Epidemiologic Studies Depression Scale. The frequency of breakfast consumption was categorized into "daily", "5-6 times/week", "3-4 times/week", "1-2 times/week", or "≤1 times/week". Logistic regression was used to estimate odds ratios of depressive symptoms according to breakfast consumption adjusted for dietary and lifestyle factors. Participants who consumed breakfast ≤1 times/week had an increased risk of depressive symptoms compared to those who ate breakfast every day, even after adjusting for other dietary factors (multivariable-adjusted odds ratio 2.92; 95% confidence interval, 1.37-6.22) The risk of depressive symptoms tended to increase with decreasing frequency of breakfast consumption (P for trend = 0.02). The omission of breakfast is related to increased risk of depressive symptoms among Japanese employees, independently of other dietary and non-dietary factors.

Systematic Review of Gut Microbiota and Major Depression

Background: Recently discovered relationships between the gastrointestinal microbiome and the brain have implications for psychiatric disorders, including major depressive disorder (MDD). Bacterial transplantation from MDD patients to rodents produces depression-like behaviors. In humans, case-control studies have examined the gut microbiome in healthy and affected individuals. We systematically reviewed existing studies comparing gut microbial composition in MDD and healthy volunteers. Methods: A PubMed literature search combined the terms "depression," "depressive disorder," "stool," "fecal," "gut," and "microbiome" to identify human case-control studies that investigated relationships between MDD and microbiota quantified from stool. We evaluated the resulting studies, focusing on bacterial taxa that were different between MDD and healthy controls. Results: Six eligible studies were found in which 50 taxa exhibited differences (p < 0.05) between patients with MDD and controls. Patient characteristics and methodologies varied widely between studies. Five phyla-Bacteroidetes, Firmicutes, Actinobacteria, Fusobacteria, and Protobacteria-were represented; however, divergent results occurred across studies for all phyla. The largest number of differentiating taxa were within phylum Firmicutes, in which nine families and 12 genera differentiated the diagnostic groups. The majority of these families and genera were found to be statistically different between the two groups in two identified studies. Family Lachnospiraceae differentiated the diagnostic groups in four studies (with an even split in directionality). Across all five phyla, nine genera were higher in MDD (Anaerostipes, Blautia, Clostridium, Klebsiella, Lachnospiraceae incertae sedis, Parabacteroides, Parasutterella, Phascolarctobacterium, and Streptococcus), six were lower (Bifidobacterium, Dialister, Escherichia/Shigella, Faecalibacterium, and Ruminococcus), and six were divergent (Alistipes, Bacteroides, Megamonas, Oscillibacter, Prevotella, and Roseburia). We highlight mechanisms and products of bacterial metabolism as they may relate to the etiology of depression. Conclusions: No consensus has emerged from existing human studies of depression and gut microbiome concerning which bacterial taxa are most relevant to depression. This may in part be due to differences in study design. Given that bacterial functions are conserved across taxonomic groups, we propose that studying microbial functioning may be more productive than a purely taxonomic approach to understanding the gut microbiome in depression.

A prospective evaluation of the depression–nutrient intake reverse causality hypothesis in a cohort of community-dwelling older Canadians

Studies have investigated the potential protective effects that diet may have on late-life depression incidence. This disorder can, however, affect the person’s food intake, widely known as the reverse causality hypothesis of depression. To test this hypothesis, we compared mean nutrient intakes from three 24-h recalls during the year depression was detected (Geriatric Depression Scale ≥11 or antidepressant medication) with intakes from 1 year earlier among community-dwelling older adults (67–83 years) followed up annually in the 4-year Québec Longitudinal Study on Nutrition and Aging, who were free of depression and cognitive impairment at baseline. Participants (n 158, 64·4 % female) who became depressed and had data available for all follow-up years were matched by age group and sex with non-depressed participants. General linear mixed models were adjusted for percentage changes in physical activity, functional autonomy and stressful life events reported at the time of positive screening. A significant group effect for the dietary intake of all three B-vitamins was observed, as depression cases had consistently lower dietary intakes than controls (P<0·01). Over time, intakes of dietary vitamin B12 declined within depressed participants in bivariate analysis, but there was no time×group effect for any nutrient tested in the multivariate analyses. Intakes of energy, protein, saturated fat and total dietary fibre did not change in cases v. controls. Among community-dwelling older adults, declines in dietary vitamins B6, B12 and folate may precede depression incidence. To help preventative efforts by programmes and practitioners, longitudinal cohorts of longer duration should investigate the extent of the decline in dietary intakes relative to the time of depression.

Intakes of folate, vitamin B6 and B12 and risk of depression in community-dwelling older adults: the Quebec Longitudinal Study on Nutrition and Aging

BACKGROUND/OBJECTIVES

Depression can decrease quality of life and affect health outcomes in older population. We investigated whether different intake levels of folate, vitamin B6 and B12 were associated with a 3-year depression incidence among generally healthy, community-dwelling older men and women.

SUBJECTS/METHODS

Participants in the Québec Longitudinal Study on Nutrition and Aging (NuAge), free of depression (that is, 30-item Geriatric Depression Scale (GDS) <11) at baseline (N=1368; 74 ± 4 years old; 50.5% women), were screened annually for incident depression (GDS ⩾ 11) or antidepressant medication. Tertiles of intakes (food only and food+supplements) were obtained from the mean of three non-consecutive 24-h recalls at baseline. Sex-stratified multiple logistic regression models were adjusted for age, physical activity, physical functioning, stressful life events and total energy intake.

RESULTS

Over 3 years, 170 participants were identified as depressed. Women in the highest tertile of B6 intake from food were 43% less likely to become depressed when adjusting for demographic and health factors (multivariate odds ratio (OR) 0.57, 95% confidence interval (CI) 0.39-0.96), but adjustment for energy intake attenuated the effect. Men in the highest tertile of dietary B12 intake had decreased risk of depression (energy-adjusted multivariate OR 0.42, 95% CI 0.20-0.90). No other association was observed.

CONCLUSIONS

This study provides some evidence of decreased depression risk among women with higher intakes of vitamin B6 from food, which was dependent on total energy intake, and among men with higher intakes of B12 from food, independently of energy intake.

Macronutrient intake and depressive symptoms among Japanese male workers: the Furukawa Nutrition and Health Study

This study was aimed to examine the cross-sectional association of protein, carbohydrate, and fat intake with depressive symptoms among 1794 Japanese male workers aged 18-69 years who participated in a health survey. Dietary intake was assessed with a validated self-administered diet history questionnaire. Depressive symptoms were assessed using the Center for Epidemiologic Studies Depression (CES-D) scale. Odds ratio of depressive symptoms (CES-D scale of ≥16) was estimated by using multiple logistic regression with adjustment for covariates including folate, vitamin B6, vitamin B12, polyunsaturated fatty acid, magnesium, and iron intake. Multivariable-adjusted odds ratio of depressive symptoms for the highest quartile of protein intake was 26%, albeit not statistically significant, lower compared with the lowest. The inverse association was more evident when a cutoff value of CES-D score ≥19 was used. The multivariable-adjusted odds ratios (95% confidence intervals) for the highest through lowest quartile of protein intake were 1.00 (reference), 0.69 (0.47-1.01), 0.69 (0.44-1.09), and 0.58 (0.31-1.06) (P for trend=0.096). Neither carbohydrate nor fat intake was associated with depressive symptoms. Our findings suggest that low protein intake may be associated with higher prevalence of depressive symptoms in Japanese male workers.

Body mass index and suicidal behaviors: a critical review of epidemiological evidence

INTRODUCTION

Obesity has been associated with an elevated risk of depression and other mental health symptoms. An increasing number of robust prospective studies, however, counter-intuitively and consistently suggested that body mass index (BMI) was inversely associated with the risk of completed suicide in a dose-response fashion. The current contribution appraised the epidemiological evidence and examined the nature of the purported relationship.

METHOD

We conducted a systematic review of English publications of original studies using the terms "obesity", "overweight", "body mass index", "BMI", "attempted suicide", "completed suicide", "suicide ideation", "suicidal behaviors" and "suicide". Data were extracted primarily through MEDLINE and PUBMED databases.

RESULTS

Almost all cohort studies reported an inverse relationship between BMI and the risk of completed suicide irrespective of region of origin and the gender of study participants. Overall, among men, a high BMI was associated with a low risk of attempted or completed suicide. There was a paradox among women, namely, a high BMI was associated with an elevated risk of attempted suicide but a low risk of completed suicide.

LIMITATIONS

As a narrative review, the current report was interpretive and qualitative in nature.

CONCLUSION

Consideration of observational data, methodological issues stemmed from the rarity of deaths by suicide, homogeneity of study populations, heterogeneity of suicide methods, and the corresponding neurobiological changes made interpretation difficult. Intercultural cohort observations across countries may help to weigh the contributions from biological and socio-cultural factors. The purported association not only represents a scientific challenge, it's also an opportunity potentially leading to important insights into prevention of suicide death.

The effects of native whey and α-lactalbumin on the social and individual behaviour of C57BL/6J mice

Milk proteins are the main components of everyday feeding and demonstrate a promising potential to change the mental condition. However, the effects of milk proteins after prolonged use remain poorly understood. The aim of the present study was to compare the effects of two whey proteins (alpha-lactalbumin (alpha-lac) and native whey) with casein on social and individual behaviour in mice. During a 30 d-long dietary intervention, male C57BL/6J mice had ad libitum access to an experimental diet containing 17% (w/w) of one of three protein sources: a-lac, native whey or casein. Mice had voluntary access to a running wheel. Social behaviour (group and resident-intruder activity) was tested at baseline and at the end of the intervention. Half of each dietary group was then withdrawn from the diet and running wheel for 7 d, and social activity and individual behaviour tests (open field, elevated-plus maze, light–dark box and forced swimming) were performed, to evaluate anxiety and depression-like status. The study shows that the long-term ingestion of whey proteins may modulate behaviour when compared with casein. Diet enriched with a-lac exhibited anxiolytic and antidepressive activities while the whey diet improved sociability. The differences between the diet groups were pronounced under the running wheel and the withdrawal of the experimental diet, suggesting that the beneficial effects of the milk proteins are clearer in stressful situations. Diet-induced behavioural changes remained visible for a week after feeding, which suggests that the proteins of the milk whey fraction have prolonged efficacy on the mental state of mice.

Dietary treatment options for depression among diabetic patient, focusing on macronutrients

There is a bidirectional adverse association between diabetes and depression. The odds for experiencing depressive symptoms in diabetic patients are two times more than nondiabetic persons, and depression is an independent predictor for the onset of diabetes. However, depression has been approximately unrecognized and untreated in two-thirds of diabetic patients, which may lead to worsened diabetes complications. A cornerstone strategy for managing depression among diabetic patients is the use of diet to improve both health problems. Because of similar pathophysiology for chronic diseases and depression, it seems that similar dietary recommendations could be useful. However, few studies have been conducted among diabetic patients. Regarding the complications of diabetes such as renal diseases and coronary heart diseases, the proper range of various macronutrients should be clarified in depressed diabetic patients as well as the proper type of each macronutrient. In this paper, we reviewed the available data on the treatment of depression in diabetic patients.