Dietary Insights in Neurological Diseases

Association Between Dietary Fiber Intake and Stroke Among US Adults: From NHANES and Mendelian Randomization Analysis

BACKGROUND

There is debate on the link between dietary fiber intake and stroke risk. The purpose of this study was to look at how it impacts dietary fiber intake and stroke risk, as well as mortality among stroke survivors. Two-sample Mendelian randomization was also used to investigate the causal relationship.

METHODS

This research examined information from 1453 patients with stroke participating in the National Health and Nutrition Examination Survey from 1999 to 2018. To assess the incidence of stroke, we conducted a survey-weighted multivariate logistic regression analysis and subgroup analysis. To evaluate the mortality associated with stroke, we used Kaplan-Meier survival analysis combined with survey-weighted Cox regression models. Using 2-sample Mendelian randomization and inverse-variance weighted method, we established a causal relationship between dietary fiber intake and stroke. The article was organized according to Strengthening the Reporting of Observational Studies in Epidemiology and Strengthening the Reporting of Observational Studies in Epidemiology Using Mendelian Randomization guidelines.

RESULTS

In the fully adjusted model, dietary fiber intake was negatively associated with stroke (odds ratio, 0.98 [95% CI, 0.97-0.99]; P<0.0001; T3 versus T1; odds ratio, 0.71 [95% CI, 0.57-0.88]; P=0.002). A stable linear negative relevance was confirmed between dietary fiber intake and stroke risk (nonlinear P=0.566) by the multivariate adjusted spline regression model. According to the survey-weighted multivariate Cox regression model, dietary fiber intake significantly reduced all-cause mortality (T3 versus T1; odds ratio, 0.68 [95% CI, 0.47-0.97]; P=0.04). Further Kaplan-Meier survival analysis indicated that higher intake of dietary fiber improved the survival of patients with stroke (P=0.02325). The 2-sample Mendelian randomization analysis showed that genetic prediction supported a causal relationship between increased dietary fiber intake and reduced risk of small vessel stroke (odds ratio, 0.8326 [95% CI, 0.7051-0.9833]; P=0.0309).

CONCLUSIONS

There is a stable negative correlation between dietary fiber intake and stroke risk. High fiber intake is associated with reduced all-cause mortality among stroke survivors. Additionally, genetic prediction further demonstrates a causal relationship between dietary fiber and reduced risk of small vessel stroke.

Metabolic Dysfunction and Dietary Interventions in Migraine Management: The Role of Insulin Resistance and Neuroinflammation-A Narrative and Scoping Review

INTRODUCTION

Migraine is a prevalent neurological disorder characterized by recurrent headaches with autonomic and neurological symptoms, significantly impacting quality of life globally. Its pathogenesis involves genetic, neurological, inflammatory, and metabolic factors, with insulin resistance and metabolic dysfunction increasingly recognized as important contributors. Historically, it has been known that certain foods can trigger migraine attacks, which led for many years to the recommendation of elimination diets-now understood to primarily target histamine-rich foods. Over the past two decades, attention has shifted toward underlying metabolic disturbances, leading to the development of dietary approaches specifically aimed at addressing these dysfunctions.

METHODS

A scoping literature review was conducted using PubMed and Embase to evaluate the relationships among migraine, insulin-related mechanisms, neurogenic inflammation, and dietary interventions. Initial searches focused on "MIGRAINE AND (neurogenic inflammation)" (2019-15 April 2025), followed by expanded searches from 1950 onward using terms such as "MIGRAINE AND (insulin, insulin resistance, hyperinsulinism)", and "MIGRAINE AND (diet, dietary, nutrition, nutritional)". A specific search also targeted "(INSULIN OR insulin resistance OR hyperinsulinism) AND (neurogenic inflammation)". Abstracts were screened, full texts were retrieved, and duplicates or irrelevant publications were excluded. No filters were applied by article type or language. Systematic reviews and meta-analyses were prioritized when available.

RESULTS

Migraine pathogenesis involves trigeminovascular system activation, neurogenic inflammation mediated by CGRP and PACAP, immune dysregulation, mast cell activation, and cortical spreading depression (CSD). Emerging evidence highlights significant associations between migraine, insulin resistance, and hyperinsulinism. Hyperinsulinism contributes to migraine through TRPV1 sensitization, increased CGRP release, oxidative stress, mitochondrial dysfunction, and systemic inflammation. Metabolic dysfunction, including obesity and insulin resistance, exacerbates migraine severity and frequency. Dietary interventions, particularly anti-inflammatory, Mediterranean, and ketogenic diets, show promise in reducing migraine frequency and severity through mechanisms involving reduced inflammation, oxidative stress, improved mitochondrial function, and glucose metabolism stabilization.

CONCLUSIONS

The interplay between insulin resistance, metabolic dysfunction, and neuroinflammation is crucial in migraine pathophysiology. Targeted dietary interventions, including ketogenic and Mediterranean diets, demonstrate significant potential in managing migraines, emphasizing the need for personalized nutritional strategies to optimize therapeutic outcomes.

Can Omega-3 fatty acid supplementation support the clinical management of drug-resistant epilepsy? A meta-analysis of randomized controlled trials

Approximately 30-40% of individuals with epilepsy develop drug-resistant epilepsy (DRE), a condition associated with substantial socioeconomic and psychological burdens for patients and their families. As standard anti-epileptic therapies often prove insufficient, alternative treatments have become a critical area of research. Dietary interventions, such as the ketogenic diet, have shown promise, and emerging evidence highlights the potential role of omega-3 fatty acids, particularly docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), due to their neuroprotective and anticonvulsant properties. However, the clinical application of omega-3 fatty acids for DRE remains uncertain due to limited high-quality randomized controlled trials (RCTs). To address this gap, we conducted a meta-analysis incorporating newly published RCTs to evaluate the clinical efficacy of omega-3 fatty acid supplementation as an adjunct to standard anti-epileptic medications in both children and adults with DRE. Our meta-analysis, incorporating high-quality RCTs, provides moderate-certainty evidence that omega-3 fatty acid supplementation, particularly at doses between 0.3 and 1.7 g/day, is associated with a reduction in seizure frequency in individuals with DRE. Notably, larger RCTs (sample size >30) demonstrated more consistent favorable outcomes. However, the evidence primarily reflects short-term effects, as the majority of included studies were of limited duration. These findings underscore the potential role of omega-3 fatty acids as an adjunctive therapy for DRE while highlighting the need for larger, long-term trials to better understand their clinical utility.

Nutrition and Dietary Patterns: Effects on Brain Function

Dietary habits are strongly associated with neuropsychological functioning [...].

The causal effects of dietary component intake and blood metabolites on risk of delirium: a Mendelian randomization study

Backgrounds

Growing evidence has indicated that the nutritional quality of dietary intake and alterations in blood metabolites were related to human brain activity. This study aims to investigate the causal relationship between dietary component intake, blood metabolites, and delirium risks.

Methods

We performed Mendelian randomization (MR) analysis using genetic variants as instrumental variables for dietary component intake, blood metabolites, and delirium. Inverse variance weighting, maximum likelihood, weighted median, weighted mode, and MR-Egger methods were used for statistical analyses.

Results

We found that genetic prediction of salt added to food (odds ratio [OR] 1.715, 95% confidence interval [CI] 1.239-2.374, p = 0.001) significantly increased the risks of delirium, while low-fat polyunsaturated margarine used in cooking (OR 0.044, 95%CI 0.004-0.432, p = 0.007), cheese intake (OR 0.691, 95%CI 0.500-0.955, p = 0.025) and coffee intake (OR 0.595, 95%CI 0.370-0.956, p = 0.032) was suggestively associated with decreased risks of delirium. Moreover, increased blood 1-stearoylglycerol levels (OR 0.187, 95%CI 0.080-0.435, p = 9.97E-05) significantly contributed to reducing the risks of delirium. 3-methoxytyrosine (OR 0.359, 95%CI 0.154-0.841, p = 0.018) also has the potential to decrease the risk of delirium.

Conclusion

Our study highlights the potential causal effect relationships of dietary component intake and blood metabolites on the risk of delirium, which potentially provides novel insights into targeted dietary prevention strategies or biomarkers for delirium.

The impact of different lifestyle factors on disability in multiple sclerosis at older ages: a monocentric retrospective study

Background

Multiple sclerosis (MS) is a chronic immune-mediated disease of the central nervous system affecting approximately 2.8 million people worldwide. In addition to genetic and environmental factors, various lifestyle factors contribute to disease development and progression.

Objectives

We performed a monocentric retrospective study and investigated the effect of lifestyle factors such as obesity, smoking, alcohol consumption, physical activity, and dietary habits on the degree of disability in a cohort of people with MS (pwMS) with an average onset of disease after the age of 55.

Design

This late-onset MS (LOMS) study group (n = 47) was characterized by a mean age of 60.9 years and a mean duration of disease of 5.0 years. The LOMS study group was compared with two control groups. The study participants in the "old control group" (Cold) were on average as old and in the "young control group" (Cyoung) as long suffering from MS as the pwMS in the LOMS group.

Methods

Data from medical documentation and a questionnaire were analyzed using descriptive frequency analyses and testing for correlation between different variables also by generalized estimating equations. The Expanded Disabilty Status Scale (EDSS) score and the progression index were used as a measure of disability.

Results

We found a significant association between smoking history and the current EDSS score in the Cyoung group, but not in the two older study groups. For physical activity, there was a significant negative correlation with EDSS score in the study group and the Cold group, alcoholic beverage consumption correlated with decreased EDSS in the Cold group. The intake of meat negatively correlated with the progression index in the LOMS group.

Conclusion

In summary, different life-style factors correlated with disability depending on patient age and disease duration. These life-style factors may be considered in the future counseling of pwMS at older ages.

Diet and Nutrients in Rare Neurological Disorders: Biological, Biochemical, and Pathophysiological Evidence

Background/Objectives: Rare diseases are a wide and heterogeneous group of multisystem life-threatening or chronically debilitating clinical conditions with reduced life expectancy and a relevant mortality rate in childhood. Some of these disorders have typical neurological symptoms, presenting from birth to adulthood. Dietary patterns and nutritional compounds play key roles in the onset and progression of neurological disorders, and the impact of alimentary needs must be enlightened especially in rare neurological diseases. This work aims to collect the in vitro, in vivo, and clinical evidence on the effects of diet and of nutrient intake on some rare neurological disorders, including some genetic diseases, and rare brain tumors. Herein, those aspects are critically linked to the genetic, biological, biochemical, and pathophysiological hallmarks typical of each disorder. Methods: By searching the major web-based databases (PubMed, Web of Science Core Collection, DynaMed, and Clinicaltrials.gov), we try to sum up and improve our understanding of the emerging role of nutrition as both first-line therapy and risk factors in rare neurological diseases. Results: In line with the increasing number of consensus opinions suggesting that nutrients should receive the same attention as pharmacological treatments, the results of this work pointed out that a standard dietary recommendation in a specific rare disease is often limited by the heterogeneity of occurrent genetic mutations and by the variability of pathophysiological manifestation. Conclusions: In conclusion, we hope that the knowledge gaps identified here may inspire further research for a better evaluation of molecular mechanisms and long-term effects.

The gut microbiota-brain axis in neurological disorders

Previous studies have shown a bidirectional communication between human gut microbiota and the brain, known as the microbiota-gut-brain axis (MGBA). The MGBA influences the host's nervous system development, emotional regulation, and cognitive function through neurotransmitters, immune modulation, and metabolic pathways. Factors like diet, lifestyle, genetics, and environment shape the gut microbiota composition together. Most research have explored how gut microbiota regulates host physiology and its potential in preventing and treating neurological disorders. However, the individual heterogeneity of gut microbiota, strains playing a dominant role in neurological diseases, and the interactions of these microbial metabolites with the central/peripheral nervous systems still need exploration. This review summarizes the potential role of gut microbiota in driving neurodevelopmental disorders (autism spectrum disorder and attention deficit/hyperactivity disorder), neurodegenerative diseases (Alzheimer's and Parkinson's disease), and mood disorders (anxiety and depression) in recent years and discusses the current clinical and preclinical gut microbe-based interventions, including dietary intervention, probiotics, prebiotics, and fecal microbiota transplantation. It also puts forward the current insufficient research on gut microbiota in neurological disorders and provides a framework for further research on neurological disorders.

Disease burden of stroke and its subtypes attributable to low dietary fiber in China, 1990-2019

This study aimed to assess the current status and changing trends of the disease burden of stroke and its subtypes due to low dietary fiber intake in China from 1990 to 2019. In cases of stroke and its subtypes attributable to low dietary fiber, deaths, disability-adjusted life-years (DALYs), age-standardized mortality rates (ASMR), age-standardized DALYs rates (ASDR), and percentage change were used to assess disease burden. Data were obtained from the 2019 global burden of disease study. Trends were assessed using Joinpoint regression and age-period-cohort analysis. Between 1990 and 2019, there was a declining trend in stroke and its subtypes, ASDR and ASMR, as well as the corresponding number of deaths and DALYs, due to low dietary fiber intake in China. Subarachnoid hemorrhage (SH) showed the greatest decrease, followed by intracerebral hemorrhage (IH) and ischemic stroke (IS). Local drift curves showed a U-shaped distribution of stroke, IS, and IH DALYs across the whole group and sex-based groups. For mortality, the overall and male trends were similar to those for DALYs, whereas female stroke, IH, and IS showed an upward trend. The DALYs for stroke and IH showed a clear bimodal distribution, IS showed an increasing risk with age. For mortality, the SH subtype showed a decreasing trend, whereas other subtypes showed an increasing risk with age. Both the period and cohort rates of stroke DALYs and motality due to low dietary fiber have declined. Males had a higher risk of DALYs and mortality associated with low fiber levels. The burden of stroke and its subtypes associated with a low-fiber diet in China has been declining over the past 30 years, with different patterns of change for different stroke subtypes and a higher burden for males, highlighting the differential impact of fiber intake on stroke and its subtypes.

Sex-dependent effects of carbohydrate source and quantity on caspase-1 activity in the mouse central nervous system

BACKGROUND

Mounting evidence links glucose intolerance and diabetes as aspects of metabolic dysregulation that are associated with an increased risk of developing dementia. Inflammation and inflammasome activation have emerged as a potential link between these disparate pathologies. As diet is a key factor in both the development of metabolic disorders and inflammation, we hypothesize that long term changes in dietary factors can influence nervous system function by regulating inflammasome activity and that this phenotype would be sex-dependent, as sex hormones are known to regulate metabolism and immune processes.

METHODS

5-week-old male and female transgenic mice expressing a caspase-1 bioluminescent reporter underwent cranial window surgeries and were fed control (65% complex carbohydrates, 15% fat), high glycemic index (65% carbohydrates from sucrose, 15% fat), or ketogenic (1% complex carbohydrates, 79% fat) diet from 6 to 26 weeks of age. Glucose regulation was assessed with a glucose tolerance test following a 4-h morning fast. Bioluminescence in the brain was quantified using IVIS in vivo imaging. Blood cytokine levels were measured using cytokine bead array. 16S ribosomal RNA gene amplicon sequencing of mouse feces was performed to assess alterations in the gut microbiome. Behavior associated with these dietary changes was also evaluated.

RESULTS

The ketogenic diet caused weight gain and glucose intolerance in both male and female mice. In male mice, the high glycemic diet led to increased caspase-1 biosensor activation over the course of the study, while in females the ketogenic diet drove an increase in biosensor activation compared to their respective controls. These changes correlated with an increase in inflammatory cytokines present in the serum of test mice and the emergence of anxiety-like behavior. The microbiome composition differed significantly between diets; however no significant link between diet, glucose tolerance, or caspase-1 signal was established.

CONCLUSIONS

Our findings suggest that diet composition, specifically the source and quantity of carbohydrates, has sex-specific effects on inflammasome activation in the central nervous system and behavior. This phenotype manifested as increased anxiety in male mice, and future studies are needed to determine if this phenotype is linked to alterations in microbiome composition.

Blood metabolomic and transcriptomic signatures stratify patient subgroups in multiple sclerosis according to disease severity

There are no blood-based biomarkers distinguishing patients with relapsing-remitting (RRMS) from secondary progressive multiple sclerosis (SPMS) although evidence supports metabolomic changes according to MS disease severity. Here machine learning analysis of serum metabolomic data stratified patients with RRMS from SPMS with high accuracy and a putative score was developed that stratified MS patient subsets. The top differentially expressed metabolites between SPMS versus patients with RRMS included lipids and fatty acids, metabolites enriched in pathways related to cellular respiration, notably, elevated lactate and glutamine (gluconeogenesis-related) and acetoacetate and bOHbutyrate (ketone bodies), and reduced alanine and pyruvate (glycolysis-related). Serum metabolomic changes were recapitulated in the whole blood transcriptome, whereby differentially expressed genes were also enriched in cellular respiration pathways in patients with SPMS. The final gene-metabolite interaction network demonstrated a potential metabolic shift from glycolysis toward increased gluconeogenesis and ketogenesis in SPMS, indicating metabolic stress which may trigger stress response pathways and subsequent neurodegeneration.

Association of multiple sclerosis with stroke: A comprehensive review

Background

Multiple sclerosis (MS) is a chronic immune-mediated disorder characterized by the degradation of the myelin sheath in the central nervous system. Research indicates that individuals with MS exhibit a higher susceptibility to stroke compared to the general population. This association is rooted in shared underlying mechanisms, specifically involving neuroinflammatory processes.

Methodology

We performed an extensive search on PubMed, MEDLINE, Embase, Scopus, and Google Scholar using specific terms. The search terms included variations of "multiple sclerosis," "stroke," "cerebrovascular disease," "vascular risk factors," "disease-modifying therapies," and "neuroinflammation." The search was limited to articles published from January 1, 2000, up to 31 May, 2023.

Results and Discussion

Stroke, a global health burden characterized by significant mortality and adult disability, underscores the critical importance of understanding the link between MS and stroke. Despite a growing body of research establishing an elevated risk of stroke in MS patients, notable information gaps persist. Limited prospective multicenter studies on stroke incidence in MS patients contribute to an incomplete understanding of the precise relationship between these two conditions.

Conclusion

In conclusion, this review underscores the critical need for a thorough understanding of the complex relationship between MS and stroke. The identified risk factors and the influence of MS DMTs on stroke risk necessitate further investigation to inform evidence-based preventive and therapeutic strategies. Bridging the existing information gaps through prospective multicenter studies is imperative for a comprehensive understanding of this association. The development of targeted diagnostic and therapeutic approaches for acute stroke risk in MS patients is paramount to mitigate the impact of these debilitating conditions. Ultimately, this review serves as a foundation for future efforts to enhance preventative measures and therapeutic interventions, thereby improving the overall quality of life for individuals with MS susceptible to strokes.

Stroke risk in multiple sclerosis: a critical appraisal of the literature

Observational studies suggest that the occurrence of stroke on multiple sclerosis (MS) patients is higher compared to the general population. MS is a heterogeneous disease that involves an interplay of genetic, environmental and immune factors. The occurrence of stroke is subject to a wide range of both modifiable and non-modifiable, short- and long-term risk factors. Both MS and stroke share common risk factors. The immune mechanisms that underlie stroke are similar to neurodegenerative diseases and are attributed to neuroinflammation. The inflammation in autoimmune diseases may, therefore, predispose to an increased risk for stroke or potentiate the effect of conventional stroke risk factors. There are, however, additional determinants that contribute to a higher risk and incidence of stroke in MS. Due to the challenges that are associated with their differential diagnosis, the objective is to present an overview of the factors that may contribute to increased susceptibility or occurrence of stroke in MSpatients by performing a review of the available to date literature. As both MS and stroke can individually detrimentally affect the quality of life of afflicted patients, the identification of factors that contribute to an increased risk for stroke in MS is crucial for the prompt implementation of preventative therapeutic measures to limit the additive burden that stroke imposes.

Oxidative stress, the blood-brain barrier and neurodegenerative diseases: The critical beneficial role of dietary antioxidants

In recent years, growing awareness of the role of oxidative stress in brain health has prompted antioxidants, especially dietary antioxidants, to receive growing attention as possible treatments strategies for patients with neurodegenerative diseases (NDs). The most widely studied dietary antioxidants include active substances such as vitamins, carotenoids, flavonoids and polyphenols. Dietary antioxidants are found in usually consumed foods such as fresh fruits, vegetables, nuts and oils and are gaining popularity due to recently growing awareness of their potential for preventive and protective agents against NDs, as well as their abundant natural sources, generally non-toxic nature, and ease of long-term consumption. This review article examines the role of oxidative stress in the development of NDs, explores the 'two-sidedness' of the blood-brain barrier (BBB) as a protective barrier to the nervous system and an impeding barrier to the use of antioxidants as drug medicinal products and/or dietary antioxidants supplements for prevention and therapy and reviews the BBB permeability of common dietary antioxidant suplements and their potential efficacy in the prevention and treatment of NDs. Finally, current challenges and future directions for the prevention and treatment of NDs using dietary antioxidants are discussed, and useful information on the prevention and treatment of NDs is provided.