Impact of a Nordic diet on psychological function in young students

Dietary patterns and insomnia symptoms: A systematic review and meta-analysis

We aimed to systematically review and synthesize the available evidence regarding the link between dietary patterns and insomnia symptoms among the general population using observational studies. We reviewed 16,455 references, of which 37 studies met inclusion criteria with a total sample size of 591,223. There was a significant association of the Mediterranean diet (OR: 0.86; 95 % CI, 0.79, 0.93; P < 0.001; I2 = 32.68 %), a high-quality diet (OR: 0.66; 95 % CI, 0.48, 0.90; P = 0.010; I2 = 84.62 %), and an empirically-derived healthy dietary pattern (OR: 0.91; 95 % CI, 0.85, 0.98; P = 0.010; I2 = 57.14 %) with a decreased risk of insomnia symptoms. Moreover, the dietary glycemic index (OR: 1.16; 95 % CI, 1.08, 1.25; P < 0.001; I2 = 0.0 %), the dietary glycemic load (OR: 1.10; 95 % CI, 1.01, 1.20; P = 0.032; I2 = 74.36 %), and an empirically-derived unhealthy dietary pattern (OR: 1.20; 95 % CI, 1.01, 1.42; P = 0.040; I2 = 68.38 %) were linked with a higher risk of insomnia symptoms. Most individual studies were of good quality (NOS) but provided very low certainty of evidence (GRADE). Consistent data reveals that following healthy diets is associated with decreased insomnia symptoms prevalence, while adherence to an unhealthy pattern is associated with an increased prevalence of insomnia symptoms.

Diet quality and anxiety: a critical overview with focus on the gut microbiome

Anxiety disorders disproportionally affect females and are frequently comorbid with eating disorders. With the emerging field of nutritional psychiatry, focus has been put on the impact of diet quality in anxiety pathophysiology and gut microbiome underlying mechanisms. While the relationship between diet and anxiety is bidirectional, improving dietary habits could better facilitate the actions of pharmacological and psychological therapies, or prevent their use. A better understanding of how gut bacteria mediate and moderate such relationship could further contribute to develop personalized programs and inform probiotics and prebiotics manufacturing. To date, studies that look simultaneously at diet, the gut microbiome, and anxiety are missing as only pairwise relationships among them have been investigated. Therefore, this study aims at summarizing and integrating the existing knowledge on the dietary effects on anxiety with focus on gut microbiome. Findings on the effects of diet on anxiety are critically summarized and reinterpreted in relation to findings on (i) the effects of diet on the gut microbiome composition, and (ii) the associations between the abundance of certain gut bacteria and anxiety. This novel interpretation suggests a theoretical model where the relationship between diet and anxiety is mediated and/or modulated by the gut microbiome through multiple mechanisms. In parallel, this study critically evaluates methodologies employed in the nutritional field to investigate the effects of diet on anxiety highlighting a lack of systematic operationalization and assessment strategies. Therefore, it ultimately proposes a novel evidence-based approach that can enhance studies validity, reliability, systematicity, and translation to clinical and community settings.

Adherence to the nordic diet is associated with anxiety, stress, and depression in recovered COVID-19 patients, a case-control study

BACKGROUND

Follow-up of COVID-19 recovered patients to discover important adverse effects on other organs is required. The psychological health of COVID-19 patients may be affected after recovery.

AIM

We aimed to evaluate the association between adherence to the Nordic diet (ND) and psychological symptoms caused by COVID-19 after recovery.

METHOD

Dietary data on 246 qualified adults (123 cases and 123 controls). The dietary intake in this case-control study was calculated by a reliable and valid food frequency questionnaire (FFQ). Depression Anxiety Stress Scale (DASS), Pittsburgh Sleep Quality Index (PSQI), Insomnia Severity Index (ISI), and Short-Form Health Survey (SF-36) were used to analyze participant's anxiety, stress, depression, sleep quality, insomnia, and quality of life of participants.

RESULTS

There was a significant inverse relationship between total anxiety, stress, and depression scores and the intake of whole grains (P < 0.05). Furthermore, there was a significant inverse association between depression and fruit intake (P < 0.05). A significant negative correlation was found between insomnia and sleep quality and the intake of root vegetables (P < 0.05). In the multinomial-regression model, a significant association between the Nordic diet and anxiety, stress, and depression was found only in the case group (OR = 0.719, 95% CI 0.563-0.918, p-value = 0.008; OR = 0.755, 95% CI 0.609-0.934, P-value = 0.010, and, OR = 0.759, 95% CI 0.602-0.956, P-value = 0.019 respectively).

CONCLUSION

Adherence to the Nordic diet might reduce anxiety, stress, and depression in recovered COVID-19 patients.

The association of hematological inflammatory markers and psychological function in COVID-19 patients: A cross-sectional study

Mental health disorders are linked to systemic inflammation. Due to high inflammation and mental health disorders in COVID-19 patients, we aimed to investigate the relationship between blood inflammatory markers such as red cell distribution width to platelet ratio (RPR), platelet-lymphocyte ratio (PLR), neutrophil/lymphocyte ratio (NLR), red cell distribution width (RDW), white blood cell (WBC), and psychological function in COVID-19 patients. In the current cross-sectional study, neuro-psychological function, and a complete blood count (CBC) were measured on 120 COVID-19 patients aged >30 years from the Imam Reza Hospital in Mashhad, Iran. Our results showed that anxiety related to MCHC (mean ± SD: 32.71 ± 1.68, p < 0.05), WBC (mean ± SD: 12.23 ± 5.43, p < 0.05), and PLR (median (IQR): 28.72 (15.88-41.31), p < 0.05) significantly. In the stress subgroup, only RPR was associated with stress (p < 0.05). Linear regression between hematological parameters and psychological score indicated that RDW and PLR had a significantly positive association with depression (β = 0.086; p = 0.045 and β = 1.326; p = 0.016, respectively) and anxiety scores (β = 0.100; p = 0.038 and β = 1.356; p = 0.010, respectively). Moreover, a positive correlation was found between PLR and stress (β = 1.102; p = 0.012). This study showed a positive association between depression/anxiety/stress symptoms and levels of hematological inflammatory markers including PLR and RDW. The findings of this study provide novel insights into mental health and physiological markers, underscoring the potential influence of inflammation on mood disorders. Our findings offer exciting prospects for future research and may lead to innovative approaches in the management and treatment of depression, anxiety, and stress.

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

Introduction

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

Methods

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

Results

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

Discussion

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

Systematic review registration

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

Predicting the Cognitive Ability of Young Women Using a New Feature Selection Algorithm

Cognitive abilities are the capabilities to perform mental processes that include executive function, comprehension, decision-making, work performance, and educational attainment. This study aimed to investigate the relationship between several biomarkers and individuals' cognitive ability using various machine learning methods. A total of 144 young women aged between 18 and 24 years old were recruited into the study. Cognitive performance was assessed using a standard questionnaire. A panel of biochemical, hematological, inflammatory, and oxidative stress biomarkers in serum and urine was measured for all participants. A novel combination of feature selection and feature scoring techniques within a hierarchical ensemble structure has been proposed to identify the most effective features in recognizing the importance of various biomarker signatures in cognitive abilities classification. Multiple feature selection methods were employed in conjunction with different classifiers to construct this model. In this manner, using three filter methods, the scores of each feature were considered. The combination of high-scoring features for each filter method was stored as the primary feature subset. A high-accuracy feature subset was selected by using a wrapper method. The collection of highly scored features from each filter method formed the primary feature subset. A wrapper method was also employed to select a feature subset with high accuracy. To ensure robustness and minimize random variations in the feature subset search process, a repeative tenfold cross-validation was conducted. The most frequently recurring features were determined. This iterative step facilitated the identification of an optimal feature subset, effectively reducing the dimensionality of features while maintaining accuracy. Among the 47 extracted factors, serum level of NOx (nitrite ± nitrate), alkaline phosphatase (ALP), and phosphate as well as blood platelet count (PLT) was entered into the model of cognitive abilities with the highest accuracy of approximately 70.9% using a decision tree classifier. Therefore, the serum levels of NOx, ALP, phosphate, and blood PLT count may be important markers of the cognitive abilities in apparently healthy young women. These factors my provide a simple procedure to identify mental abilities and earlier cognitive decline in healthy adults.

The Relationship between Whole-Grain Intake and Measures of Cognitive Decline, Mood, and Anxiety-A Systematic Review

Greater intake of whole grains, compared to refined grains, is consistently associated with a reduced risk of cardiovascular disease and type 2 diabetes, both of which are associated with cognitive decline. To better understand the relationship between whole-grain intake, cognition, mood, and anxiety, a systematic review was conducted to synthesize available evidence linking whole grains to these outcomes. Four electronic databases were searched from inception to August 2021 for potentially relevant observational and interventional studies. Risk of bias (RoB) assessments were performed using the newly developed Nutrition Quality Evaluation Strengthening Tools, and the Grades of Recommendation, Assessment, Development, and Evaluation approach was used to determine the strength of evidence for each outcome. In total, 23 studies [4 randomized controlled trials (RCTs) and 19 observational studies] met the predefined eligibility criteria. Of these,12 studies included analysis of whole-grain intake and cognitive decline, 9 included mood outcomes, and 2 included both cognition and mood outcomes. The overall evidence for an association between whole-grain intake and cognition is inconclusive. With respect to mood outcomes, evidence from RCTs prospective cohort and case-control studies suggest that higher intake is linked to improved outcomes for mood and depression although the evidence is mixed for cross-sectional studies. Reporting of whole-grain intake fell short of suggested standards, and the strength of available evidence was low or very low for all outcomes. A high RoB toward studies reporting results was also noted, complicating both the interpretation of some studies and the combined evidence. Of note, few well-designed RCTs assessing the effect of whole-grain intake on measures of cognition, mood, and anxiety were identified, highlighting the need for more studies in this area. The available, although limited, evidence suggests that greater whole-grain intake is associated with better mood and anxiety-related scores and is inconclusive regarding cognitive outcomes. PROSPERO registration: CRD42021266355.

The relationship between food quality score with inflammatory biomarkers, and antioxidant capacity in young women

Diet has the potential to decrease oxidative stress and inflammation and this may be beneficial in several diseases. This study investigated the association between food quality score (FQS) with antioxidant and inflammatory properties in 171 apparently healthy young women. This cross-sectional study was conducted using a validated food frequency questionnaire to determine the dietary intake of participants. FQS was calculated by summing all the scores obtained from healthy and unhealthy food groups. The total antioxidant capacity and free radical scavenging activity of serum and urine were quantified using the ferric reducing/antioxidant power (FRAP) and α, α-diphenyl-β-picrylhydrazyl (DPPH) methods, respectively. Malondialdehyde (MDA) was measured using the formation of thiobarbituric acid reactive substances (TBARS). White blood cell (WBC) and neutrophil counts, mean platelet volume (MPV) and red blood cell distribution width (RDW), were measured. Neutrophil: lymphocyte ratio (NLR), platelet: lymphocyte ratio (PLR), and RDW: platelet ratio (RPR) were also calculated. A high food quality (rich in fruit and vegetables, nuts, whole grain, and low intake of sweetened beverage, potato chips and fried food from outside the home) was related to lower hematological inflammatory biomarkers including WBC count, RDW, NLR, and PLR. Multivariable-adjusted odds ratios (95% CIs) demonstrated that higher FQS group (third tertile vs. first tertile) was associated with a significant lower levels of urinary FRAP (ORadj  = 0.82; 95%CI: 0.70 to 0.97), and DPPH. High food quality was associated with reduced of markers of inflammation and oxidative stress in Iranian young girl.

Evaluation of the pharmacological effects and exploration of the mechanism of traditional Chinese medicine preparation Ciwujia tablets in treating insomnia based on ethology, energy metabolism, and urine metabolomic approaches

Ciwujia Tablets (CWT) are produced by concentrating and drying the extract solution of the dried rhizome of Eleutherococcus senticosus (Rupr. & Maxim.) Maxim [Araliaceae; E. senticosus radix et rhizoma]. Besides, CWT is included in the 2020 edition of Chinese Pharmacopoeia and is widely used in the treatment of insomnia. It mainly contains eleutheroside B, eleutheroside E, isofraxidin, eleutheroside C, ciwujiatone, and chlorogenic acid, as well as other chemical components. Although the clinical efficacy of CWT in treating insomnia has been confirmed, its functions and pharmacological effects have not been systematically evaluated and its mechanism of action in the treatment of insomnia remains unclear. Therefore, in this study, behavioral, energy metabolism, and metabonomics methods were applied to systematically evaluate the effect of CWT on insomnia. Additionally, urine metabonomics based on UPLC-Q-TOF-MS/MS were utilized to identify potential endogenous biomarkers of insomnia, detect the various changes before and after CWT treatment, explore the metabolic pathway and potential target of CWT, and reveal its pharmacological mechanism. Results revealed that CWT increased inhibitory neurotransmitter (5-HT and GABA) content and reduced the content of excitatory neurotransmitters (DA and NE). Moreover, CWT enhanced autonomous behavioral activity, stabilized emotions, and promoted the return of daily basic metabolic indexes of insomniac rats to normal levels. The urine metabolomics experiment identified 28 potential endogenous biomarkers, such as allysine, 7,8-dihydroneopterin, 5-phosphonooxy-L-lysine, and N-acetylserotonin. After CWT treatment, the content of 22 biomarkers returned to normal levels. The representative markers included N-acetylserotonin, serotonin, N-methyltryptamine, and 6-hydroxymelatonin. Additionally, the metabolic pathways in rats were significantly reversed, such as tryptophan metabolism, folate biosynthesis, phenylalanine metabolism, and tyrosine metabolism. Ultimately, it is concluded that CWT regulated tryptophan metabolism, folate biosynthesis, phenylalanine metabolism, and other metabolic levels in the body. This drug has been confirmed to be effective in the treatment of insomnia by regulating the content of serotonin, 6-hydroxymelatonin, N-acetylserotonin, and N-methyltryptamine to a stable and normal level in tryptophan metabolism.

The association between adherence to a dietary approaches to stop hypertension (DASH) diet and neuro-psychological function in young women

Background

The adherence to a Dietary Approaches to Stop Hypertension (DASH) diet may have a bidirectional relationship with mental wellbeing. We aimed to evaluate the association between compliance with a DASH diet and neuro-psychological function in young women.

Methods

In this cross-sectional study, a total of 181 girls aged between 18 and 25 years were recruited. The dietary intakes of study participants were evaluated using a valid and reliable food frequency questionnaire (FFQ) containing 65 food items. Neuropsychological function of participants was evaluated using standard questionnaires.

Results

As may be expected, individuals in the highest tertile (T3) of adherence to DASH diet (highest adherence) were found to consume more folate, fruits, vegetables, low fat dairy, nuts, legume, and seed, less sweetened beverage and sodium, compared to the participants in the lowest tertile (T1, lowest adherence). There was a significant negative correlation between cognitive function and consumption of red and processed meat (r = − 0.168; p < 0.05); quality of life score with dietary sodium (r = − 0.151; p < 0.01) and depression score with dietary vegetables (r = − 0.174; p < 0.05). In multivariate multinomial logistic regression analyses adjusted for age, BMI and energy intake, adherence to a DASH-style diet was associated with a lower stress score (OR = 0.70; 95%CI: 0.34–1.47, P = 0.067; T3 vs. T1) and difficulty with sleep initiation (OR = 0.46; 95%CI: 0.21–1.00, P = 0.017; T3 vs. T1).

Conclusion

Adherence to a DASH diet may be associated with reduced stress and difficulty with initiating sleep.