Dietary fibre in gastrointestinal health and disease

Microbial micronutrient sharing, gut redox balance and keystone taxa as a basis for a new perspective to solutions targeting health from the gut

In health, the gut microbiome functions as a stable ecosystem maintaining overall balance and ensuring its own survival against environmental stressors through complex microbial interaction. This balance and protection from stressors is maintained through interactions both within the bacterial ecosystem as well as with its host. As a consequence, the gut microbiome plays a critical role in various physiological processes including maintaining the structure and function of the gut barrier, educating the gut immune system, and modulating the gut motor, digestive/absorptive, as well as neuroendocrine system all of which are crucial for human health and disease pathogenesis. Pre- and probiotics, widely available and clinically established, offer various health benefits primarily by beneficially modulating the gut microbiome. However, their clinical outcomes can vary significantly due to differences in host physiology, diets, individual microbiome compositions, and other environmental factors. This perspective paper highlights emerging scientific insights into the importance of microbial micronutrient sharing, gut redox balance, keystone species, and the gut barrier in maintaining a diverse and functional microbial ecosystem, and their relevance to human health. We propose a novel approach that targets microbial ecosystems and keystone taxa performance by supplying microbial micronutrients in the form of colon-delivered vitamins, and precision prebiotics [e.g. human milk oligosaccharides (HMOs) or synthetic glycans] as components of precisely tailored ingredient combinations to optimize human health. Such a strategy may effectively support and stabilize microbial ecosystems, providing a more robust and consistent approach across various individuals and environmental conditions, thus, overcoming the limitations of current single biotic solutions.

Personalized Dietary Approaches to Optimizing Intestinal Microbial Health and Homeostasis

Diet has a profound impact in human health, which is partly driven by changes in the intestinal microbiota. Several associations between dietary intake and the intestinal microbiota composition and function have been described. Namely, the Mediterranean diet is associated with beneficial bacteria, while the intake of ultraprocessed foods is linked to dysbiosis. It is, therefore, very tempting to tailor dietary approaches to the individual needs of the microbiota; however, high-quality prospective data are lacking. Provisionally, a diet rich in fruits and vegetables and low in ultraprocessed foods is recommended to improve the intestinal microbiota composition and function.

Dietary fiber intake, genetic predisposition of gut microbiota, and the risk of metabolic dysfunction-associated steatotic liver disease

This study aimed to explore the association between dietary fiber intake and the risk of metabolic dysfunction-associated steatotic liver disease (MASLD), as well as liver fat content, while considering genetic predispositions of MASLD, gut microbial abundance, and butyrate levels. This study analyzed data from 190,276 participants in the UK Biobank. Dietary fiber intake was assessed using 24-h dietary recall. MASLD cases were diagnosed through hospital admission records and death registries, and liver fat content was measured via magnetic resonance imaging. The genetic predispositions of MASLD, gut microbial abundance, and butyrate levels were evaluated using single nucleotide polymorphisms. Cox proportional hazards models were used to calculate hazard ratios (HRs) and 95 % confidence intervals (CIs). Over a median follow-up of 10.49 years, 1423 MASLD cases were recorded. Elevated dietary fiber intake was associated with a reduced risk of MASLD (HR: 0.72; 95 % CI: 0.58, 0.90) and a lower level of liver fat content (β: -0.97; 95 % CI: -1.21, -0.73) (all P for trend <0.05). Restricted cubic spline analyses further confirmed the linear inverse associations between fiber intake and the risk of MASLD. Notably, the negative associations between dietary fiber intake and both MASLD and liver fat content were consistent across different genetic predispositions of gut microbial abundance and butyrate levels. Moreover, the inverse association between dietary fiber intake and liver fat was strengthened by high genetic susceptibility of MASLD and elevated body mass index (both P for interaction <0.05). Overall, increased dietary fiber consumption was associated with a lower MASLD risk and decreased liver fat content regardless of genetic predispositions of gut microbial abundance and butyrate levels.

Psyllium husk powder enhances the management of type 2 diabetes by modulating gut microbiota and their metabolic products

Type 2 diabetes mellitus (T2DM) is a complex metabolic disorder characterized by hyperglycemia and insulin resistance. Plantain shell powder (PHP) serves as a high-quality source of dietary fiber, widely utilized in food additives and pharmaceutical applications. In this study, we investigated the hypoglycemic activity and underlying mechanisms of PHP by examining its effects on intestinal microbiota and metabolism in T2DM mice induced by a high-fat diet and streptozotocin (STZ). Our findings indicate that PHP significantly enhances blood glucose homeostasis and insulin sensitivity, reduces organ damage, and regulates blood lipid levels as well as short-chain fatty acid concentrations; notably, higher doses of PHP yielded optimal results. In addition, PHP can regulate the ratio of Bacteroidota to Firmicutes and increase the relative abundance of beneficial bacteria such as Bacteroidales, Muribaculaceae, and Parabacteroides. Furthermore, PHP enhances the enrichment of key metabolic pathways, including α-linolenic acid metabolism, monobactam biosynthesis, and PPAR signaling pathways, thereby promoting the production of beneficial metabolites. Complex interactions exist among these beneficial bacteria and metabolic pathways that are associated with improved metabolic function, regulation of glucose homeostasis, enhancement of insulin sensitivity, and reduction of inflammation. Our study demonstrates that PHP can ameliorate T2DM by reversing alterations in gut microbiota and metabolic profiles caused by T2DM while promoting the regulation of beneficial microbial populations.

Synthesis and characterization of a delivery system by combining cobalt (II) with soluble dietary fiber from Cyperus esculentus L. to regulate gut-derived neuroactive metabolite biosynthesis

Cobalt (Co) deficiency significantly impacts vegetarians and individuals with malabsorption disorders. To enhance loading efficiency, safety, and bioavailability of Co, a novel organic delivery system, CESDF-Co (II), was constructed using soluble dietary fiber from Cyperus esculentus L. (CESDF) as an organic ligand, synthesized using a microwave-assisted solid-phase method. Comprehensive analyses were conducted to determine the structural characteristics of CESDF-Co (II) and evaluate its stability, targeted release efficiency, and potential to regulate the biosynthesis of gut-derived neuroactive metabolites. Results revealed the formation of a three-dimensional cross-linked network within the CESDF-Co (II) due to Co (II) coordination bridging, with a cobalt loading of 78.14 mg/g. This structure enhanced its thermal stability and surface hydrophobicity while retaining the intrinsic resistance of CESDF to gastrointestinal digestion, facilitating colon-targeted delivery of CESDF-Co (II). In vitro fermentation demonstrated that CESDF-Co (II) significantly increased neuroactive-related amino acid precursors (tryptophan, tyrosine, glutamic acid, and methionine by 2.04-, 2.92-, 2.33-, and 2.58-fold, respectively) and neurotransmitters (serotonin, γ-aminobutyric acid, dopamine, and acetylcholine by 3.28-, 4.93-, 1.73-, and 1.54-fold, respectively). This enhancement positively correlated with increased production of total short-chain fatty acids (1.57-fold) and cobalt-dominated vitamin B12 synthesis (16.25-fold). These findings offer valuable insights for constructing secure colon-targeted, microbiota-triggered release delivery systems.

Efficient conversion of insoluble dietary fiber to soluble dietary fiber by Bacillus subtilis BSNK-5 fermentation of okara and improvement of their structural and functional properties

Bacillus subtilis exhibits strong adaptability and biotransformation potential in the fermentation of okara, but the effects of fermentation on their dietary fiber remain unclear. This study explored the impact of Bacillus subtilis BSNK-5 fermentation on converting insoluble dietary fiber (IDF) to soluble dietary fiber (SDF) in okara, focusing on structural and functional changes. After 72 h of fermentation, SDF increased 7.51-fold. The surface folds of fermented IDF were reduced. Meanwhile, SDF displayed a more porous structure with significant changes in its crystalline structure. FTIR analysis showed that surface disruption exposed both hydrophilic and hydrophobic groups. Thermal analysis showed that the peak of maximum degradation moved to a lower temperature. Both fermented SDF and IDF exhibited antioxidant activity, effective lipid- and glucose-lowering effects. These findings suggest that BSNK-5 effectively transforms IDF into SDF, with fermented dietary fiber showing great potential as a functional ingredient in the food industry.

Dietary selection of distinct gastrointestinal microorganisms drives fiber utilization dynamics in goats

BACKGROUND

Dietary fiber is crucial to animal productivity and health, and its dynamic utilization process is shaped by the gastrointestinal microorganisms in ruminants. However, we lack a holistic understanding of the metabolic interactions and mediators of intestinal microbes under different fiber component interventions compared with that of their rumen counterparts. Here, we applied nutritional, amplicon, metagenomic, and metabolomic approaches to compare characteristic microbiome and metabolic strategies using goat models with fast-fermentation fiber (FF) and slow-fermentation fiber (SF) dietary interventions from a whole gastrointestinal perspective.

RESULTS

The SF diet selected fibrolytic bacteria Fibrobacter and Ruminococcus spp. and enriched for genes encoding for xylosidase, endoglucanase, and galactosidase in the rumen and cecum to enhance cellulose and hemicellulose utilization, which might be mediated by the enhanced microbial ATP production and cobalamin biosynthesis potentials in the rumen. The FF diet favors pectin-degrading bacteria Prevotella spp. and enriched for genes encoding for pectases (PL1, GH28, and CE8) to improve animal growth. Subsequent SCFA patterns and metabolic pathways unveiled the favor of acetate production in the rumen and butyrate production in the cecum for SF goats. Metagenomic binning verified this distinct selection of gastrointestinal microorganisms and metabolic pathways of different fiber types (fiber content and polysaccharide chemistry).

CONCLUSIONS

These findings provide novel insights into the key metabolic pathways and distinctive mechanisms through which dietary fiber types benefit the host animals from the whole gastrointestinal perspective. Video Abstract.

Diet, nutraceuticals, and lifestyle interventions for the treatment and management of irritable bowel syndrome

Irritable bowel syndrome (IBS) is the most common gastrointestinal (GI) disorder of the gut-brain interaction and causes significant GI distress. The etiology of IBS is multifactorial, with food intolerances being a frequent contributing factor to IBS symptoms. Diet and lifestyle interventions are key components in comprehensive IBS care. In this review, we examine the current evidence-based dietary approaches for treating IBS. The low-FODMAP diet has the most robust data for improving overall symptom burden. In conjunction with guidance from a registered dietitian, certain patients may benefit from targeted dietary elimination of specific carbohydrates such as lactose or fructose or gluten. Among the nutraceuticals used to treat IBS, peppermint oil has sufficient evidence and appropriate safety data to recommend adjunctive use to reduce IBS symptoms. Although prebiotic and probiotic food sources may be beneficial to the microbiome, there is not enough evidence to support the routine use of prebiotic or probiotic supplements. Given the complexity of IBS, a holistic approach in which clinicians address a patients' diet, culture, sleep hygiene, exercise habits, and mental health may improve patients' overall quality of life.

Citrus endogenous components as prebiotics: Advances in extraction, digestion, mechanisms, and delivery

The large number of by-products during the processing of citrus fruits exert significant pressure on the environment. Citrus by-products contain a variety of bioactive compounds that promote gut health and maintain microbial homeostasis. Therefore, recycling and reuse of these by-products is considered an excellent way to reduce environmental pressure. The purification and characterization methods of bioactive compounds (such as pectin, dietary fiber, polyphenols, essential oils, and limonin) extracted from citrus by-products in recent years are summarised. Subsequently, we summarize the digestive behavior (digestion, absorption, metabolism, and excretion) of these components, focusing on the mechanisms of action through which they exert prebiotic activity. This highlights the interactions between citrus by-product bioactives and gut microbiota, as well as the health effects on the host gut. Additionally, we provide a brief overview of the delivery systems for the active ingredients based on pectin from citrus sources. The results show that extraction methods can significantly affect the composition and structure of citrus by-products, which in turn affects digestive properties and eventually leads to differences in prebiotic activity. Notably, gut microbiota plays a key role in the metabolism and bioactivity of citrus actives. Besides, the innovative embedding methods can markedly enhance their prebiotic potential. Therefore, a comprehensive understanding of the relationship between the extraction, structure, and prebiotic activity of citrus by-products, as well as their delivery methods, is essential to advancing the use of citrus by-products in human health.

Expandable konjac fiber modulates appetite and chyme digestion in vivo by stomach-intestine-brain axis

Appetite regulation is a lifestyle intervention strategy to maintain health. The regulatory effects of dietary fiber (especially insoluble dietary fiber), as a crucial element of the nutritional composition, on appetite remain poorly understood. This study investigated modulatory effects of konjac fiber (KF, with high and low expansion) and konjac powder (KP) on chyme digestion, gastrointestinal hormones, intestinal microbiota, appetite genes in hypothalamus, GLP-1 receptor (GLP-1R) protein in various tissues of rats by dietary intervention. The results showed that highly-expanded konjac fiber (HKF) significantly delayed gastric emptying and inhibited hydrolysis of chyme. Konjac fiber (KF), especially HKF, and KP increased short-chain fatty acid (SCFA) content and plasma glucagon-like peptide-1 (GLP-1) levels. HKF upregulated the expression of GLP-1R protein in rat stomachs, nucleus tractus solitaries (NTS), and area postrema (AP) of rat brain, but down-regulated the expression of appetite gene AgRP/NPY in hypothalamus, thus, inhibiting appetite, reducing daily food intake and weight gain. Overall, this study reveals the mechanism through which expandable konjac fiber modulates appetite and chyme digestion in vivo by stomach-intestine-brain axis. Our findings provide an insight into the regulatory effects of insoluble dietary fiber on appetite and offered a valuable reference for the development of satiety-enhancing functional foods.

Insoluble dietary fibers from Hancornia speciosa alleviates chronic constipation on experimental loperamide-induced model

Constipation is one of the most prevalent intestinal disorders and is characterized by the presence of hard and dry stools, excessive effort, infrequent bowel movements, abdominal distension and pain, and others. Low fiber consumption may be one of the nutritional factors that greatly influence the development of constipation. Previous studies have observed the laxative effect of Hancornia speciosa fruit pulp. So, this study aims to extract and characterize the dietary fibers from H. speciosa fruit pulp and evaluate the laxative effect of both soluble (SDF) and insoluble (IDF) fractions on an experimental model of loperamide-induced chronic constipation. Monosaccharide and NMR analyses showed that SDF and IDF fractions were mainly composed of arabinose, indicating the presence of pectic arabinans. No changes on food and water intake and weight gain were observed. IDF fraction induced a threefold increase in number, weight and water content of fecal pellets and doubled small intestine transit rate. Similar results were obtained for SDF in a smaller intensity. Both fractions decreased the number of leukocytes in small and large intestines, suggesting a potential anti-inflammatory effect. Thus, the dietary fiber fractions from H. speciosa were effective in improving fecal parameters and alleviating constipation symptoms in the evaluated model.

Effects of wheat cultivar, oligosaccharide, inulin, arabinoxylan and endoxylanase on the large- and small-strain rheological properties and microstructure of dietary fibre enriched dough

To overcome the processing challenges and quality issues of high-fibre products, this research was conducted to investigate how the formulation, i.e., wheat cultivar, dietary fibre (DF) and endoxylanase, affected the rheological properties and microstructure of DF-enriched doughs. Doughs prepared from stronger wheat cultivars had a better tolerance to DF addition. A two-fold decrease in the gel strength of dough was observed with the DF addition from 0 to 12 %. This weakening effect on the dough was reversed due to the endoxylanase addition, i.e., an increase of 23-36 % for gel strength parameters. The endoxylanase-induced modification for dough microstructure was also seen as a more uniform distribution of gluten proteins, starch granules and gas cells. This work will provide the high-fibre food industry with an optimized formula that ensures the final products with a satisfactory overall quality and consumer acceptability.

Common misconceptions and controversies in the management of irritable bowel syndrome

Despite an increase in our understanding of the pathophysiology of irritable bowel syndrome (IBS), in the context of abnormal gut-brain axis communication, and advances in both pharmacological and non-pharmacological treatment of the disorder, there remain areas in which there are misconceptions and controversies in the clinical management of IBS. This Perspective aims to highlight some of the most common misconceptions and controversies in IBS management, including those that the scientific literature has resolved, but for which further education of clinicians dealing with patients with IBS might be required to implement the findings from medical research. Areas of remaining contention are also discussed, as are suggestions as to how these issues could be addressed, both by advances in clinical practice and by further research.

The relationship of cardiometabolic index with bowel movement frequency: an NHANES-based cross-sectional analysis

BACKGROUND

Prior studies have indicated a notable link between gut health and metabolic syndrome (MetS). The cardiometabolic index (CMI), an innovative indicator of metabolic health, effectively predicts MetS. Bowel movement frequency (BMF) closely reflects gastrointestinal function and is a key sign of gut health. Nonetheless, the relationship between CMI and BMF is still unclear. Our research explores the possible association between these two variables.

METHODS

This study employed 2005 to 2010 National Health and Nutrition Examination Survey data. The CMI for each participant was determined by triglycerides, high-density lipoprotein cholesterol, and the waist-to-hip ratio. Multiple regression, smooth curve fitting, and threshold effect analyses were employed to investigate the association between CMI and BMF. The association's stability across populations was assessed through subgroup analyses and interaction tests.

RESULTS

The study included 9,678 participants in total. After controlling for potential confounding variables, those in the uppermost CMI quartile had a 0.69 more increase in BMF than the bottom quartile (β = 0.69, 95% CI: 0.34, 1.03). The trend analyses showed that BMF increased steadily with the advancement of the CMI quartiles (P for trend < 0.0001). Associations between CMI and BMF were shown to be nonlinear through smooth curve fitting and threshold effect analyses. Specifically, when CMI ranged from 4.97 to 11.75, a negative connection was observed (β = -0.78, 95% CI: -1.33, -0.23), while positive associations were identified in other ranges. Subgroup analyses and interaction tests indicated significant CMI and BMF association variations when stratified by depression and age categories (P for interaction < 0.05).

CONCLUSIONS

This research indicates that CMI is generally associated with an increase in BMF. However, when CMI ranges from 4.97 to 11.75, it is associated with a BMF decrease. Notably, the association of CMI and BMF is more potent in young, middle-aged, and depressed people.

Modification of coconut insoluble dietary fiber by enzymatic extraction and high-pressure homogenization: physicochemical property changes and inhibitory effects on pancreatic lipase activity

In this study, coconut insoluble dietary fiber (CIDF) was modified by high-pressure homogenization (HPH), and the physicochemical properties and pancreatic lipase (PL) inhibitory activity were investigated. HPH diminished the particle size of CIDF (859.90 nm to 232.80 nm) and increased the total surface area and gap ratio. HPH enhanced the water and oil holding capacities of CIDF from 6.01 to 10.33 g/g and from 6.52 to 9.87 g/g, respectively. CIDF markedly inhibited PL activity by up to 72.51 % (p < 0.05), with the inhibition rate of PL was significantly higher in HPH-modified CIDF than in unmodified CIDF. The exposure of CIDF's hydroxyl groups due to the HPH treatment directly affected the degree of binding of CIDF to PL. CIDF reduces PL activity through hydrogen bonding and hydrophobic interactions with its aromatic amino acid residues.

In vitro effects of structurally diverse low molecular weight chondroitin sulfates on gut microbiota and metabolome

In this study, low molecular weight chondroitin sulfates (LMCSs) with different structures, named LMCSO, LMCSD, and LMCSH, were prepared by oxidative degradation, deamidation cleavage, and hydrothermal depolymerization, respectively. In vitro fermentation modeling was used to study the effects of CS and LMCSs on gut microbiota and metabolite composition. The degree of carbohydrate metabolism was in the order of CS > LMCSH > LMCSO > LMCSD. Significantly, GlcA in chondroitin-6-sulfate (CSC) was more readily utilized by gut microbiota during fermentation, and this trend was more pronounced in LMCSs. The LMCSs group notably increased microbial richness and evenness, especially in the LMCSD group. Bacteroides fragilis was identified as a potential primary degrader of CS and LMCSs through species-level analysis. The abundance of Escherichia-Shigella was reduced by LMCSs, and short-chain fatty acids production was enhanced, particularly by LMCSO, while the production of beneficial metabolites such as N-acetyl-D-Glucosamine 6-Phosphate (GlcNAc-6P), lactate, and progesterone was stimulated. Among these, the metabolism of the key metabolite GlcNAc-6P was significantly and positively correlated with the abundance of Bacteroides, Clostridium_sensu_stricto_1, and Parabacteroides. Exploring the mechanisms by which gut microbiota metabolize LMCSs with different structures can provide theoretical support for the targeted preparation of LMCSs that modulate the gut microbiota.

Food-Based Interventions as Therapy for Inflammatory Bowel Disease: Important Steps in Diet Trial Design and Reporting of Outcomes

Diet therapy for inflammatory bowel disease (IBD) is an international research priority but guidance for IBD-specific diet trial design is lacking. This review critically evaluates key elements of prospective IBD food-based intervention trials and identifies gaps. Electronic databases were searched for interventional IBD diet studies. Prospective primary studies/trials were included if used food-based dietary strategies. Forty studies/trials evaluating 29 food-based strategies as therapy for IBD were identified. Considerable heterogeneity in diets, trial design, and methodology exists. Thirty-one trials (78%) intended the diet to modulate inflammation but 14/31 (46%) did not have a primary endpoint measuring an objective change in inflammatory activity and 20/31 (65%) controlled for medication stability prior to application of diet at baseline. Higher-quality IBD diet trials used symptom-based assessment tools coupled with an objective evaluation of inflammatory activity. Dietary advice trials are the most common. One-third of trials developed and administered diet education without a dietitian. Evaluation and reporting on adherence to diet therapy occurred in <60% of trials. Failure to include or report on key elements of trial design reduced the interpretability and validity of the results. This is a considerable limitation to advancing scientific knowledge in this area. Diet therapy trials should adhere to similar rigorous quality standards used to develop other IBD therapies. Therefore, a set of practical recommendations was generated to provide the authors' perspective to help inform the future design of high-quality IBD diet trials.

Phyto-metabolites on guard: Role of gut microbial deglycosylation

Plant phenolic glycosides are thought to be beneficial for human health. In a recent issue of Cell, Kuziel et al. identified that Bacteroides species, the dominant symbiotic bacteria in the gut, harbor a unique multi-enzyme system that processes dietary plant glycosides into various aglycone metabolites with antimicrobial or immunomodulatory activities.

Valorization of bioactive compounds from food by-products using supercritical fluid extraction: A technological and industrial perspective

Food loss and waste (FLW) present significant challenges worldwide, affecting food supply, economic efficiency, and environmental sustainability. Supercritical fluid extraction (SFE) offers a promising solution for valorizing food by-products, addressing challenges related to FLW through efficient extraction of bioactive compounds. This review evaluates SFE's efficacy in extracting high-value compounds, including phenolics, terpenes, terpenoids, essential fatty acids, and dietary fibers, from food by-products. In addition, recent technological advancements are explored, with a focus on optimizing processing parameters, pretreatment methods, and integrating sequential extraction techniques to improve SFE efficiency. Industrial applications and the potential for broader commercial adoption are discussed, with attention to scalability, economic feasibility, and regulatory considerations. In conclusion, SFE is presented as a sustainable approach for converting food by-products into high-value bioactives. The integration of complementary technologies and further research on scalability are crucial for overcoming current limitations.

Sports Dietitians Australia and Ultra Sports Science Foundation Joint Position Statement: A Practitioner Guide to the Prevention and Management of Exercise-Associated Gastrointestinal Perturbations and Symptoms

It is now well-established that exercise can disturb various aspects of gastrointestinal integrity and function. The pathophysiology of these perturbations, termed "exercise-induced gastrointestinal syndrome (EIGS)," can lead to exercise-associated gastrointestinal symptom (Ex-GIS) inconveniences. EIGS outcomes can impact physical performance and may lead to clinical manifestation warranting medical intervention, as well as systemic responses leading to fatality. Athlete support practitioners seek prevention and management strategies for EIGS and Ex-GIS. This current position statement aimed to critically appraise the role of EIGS and Ex-GIS prevention and management strategies to inform effective evidence-based practice and establish translational application. Intervention strategies with mostly consistent beneficial outcomes include macronutrient (i.e., carbohydrate and protein) intake and euhydration before and during exercise, dietary manipulation of fermentable oligo-, di-, and mono-saccharides and polyols (FODMAP), and gut training or feeding tolerance adjustments for the specific management of Ex-GIS from gastrointestinal functional issues. Strategies that may provide benefit and/or promising outcomes, but warrant further explorations include heat mitigating strategies and certain nutritional supplementation (i.e., prebiotics and phenols). Interventions that have reported negative outcomes included low-carbohydrate high-fat diets, probiotic supplementation, pharmaceutical administration, and feeding intolerances. Owing to individual variability in EIGS and Ex-GIS outcomes, athletes suffering from EIGS and/or support practitioners that guide athletes through managing EIGS, are encouraged to undertake gastrointestinal assessment during exercise to identify underlying causal and exacerbation factor/s, and adopt evidence-based strategies that provide individualized beneficial outcomes. In addition, abstaining from prevention and management strategies that present unclear and/or adverse outcomes is recommended.

Interest of inulin in obesity: comparison of the prebiotic effect of edible-food sources versus purified inulin from chicory root

PURPOSE

Inulin-type fructans (ITF) are fermentable dietary fibres (DF) that can confer beneficial metabolic health effects through changes in the gut microbiota. Many papers suggest that complex food rich in DF could be more relevant than purified DF in terms of health effect. We compared the prebiotic effect of natural source of inulin (scorzonera) versus native inulin extracted from chicory root in a model of obesity.

METHODS

Mice were fed during 6 weeks a low-fat (LF), high-fat (HF) or high-fat diet enriched with either purified inulin from chicory root (Inu) or lyophilized scorzonera (Sco), with the same amount of ITF intake (10%) versus a non-fermentable fibre (cellulose). Metabolic parameters were correlated with the gut microbiome composition (16S rRNA gene sequencing).

RESULTS

Both inulin sources reduced food intake without significantly modifying body weight gain or adiposity compared to HF. Purified inulin and lyophilized scorzonera differentially modulate the gut physiology and microbiota. Both inulin and scorzonera shifted global gut microbial composition from HF group, decreased members of Desulfovibrionaceae and boosted bifidobacteria level. Some effects were specific to Sco group, such as the increase of Akkermansia and the decrease of Bacteroides, that correlated to biological outcomes. Inu improved hepatic steatosis whereas scorzonera boosted intestinal immunity markers and antimicrobial peptides expression, and increased intestinal crypt depth.

CONCLUSION

Differences occur between natural edible versus isolated sources of ITF. Both sources of inulin shifted the gut microbiota, but differently affected intestinal and lipid homeostasis. This study highlights the importance of food matrix and origins of fructans for their use in the context of metabolic disorders.

Impact of Nutrition on the Gut Microbiota: Implications for Parkinson's Disease

Parkinson's disease (PD) is a multifactorial neurodegenerative disease that is characterized by the degeneration of dopaminergic neurons in the substantia nigra pars compacta and by the anomalous accumulation of α-synuclein aggregates into Lewy bodies and Lewy neurites. Research suggests 2 distinct subtypes of PD: the brain-first subtype if the pathology arises from the brain and then spreads to the peripheral nervous system (PNS) and the body-first subtype, where the pathological process begins in the PNS and then spreads to the central nervous system. This review primarily focuses on the body-first subtype. The influence of the gut microbiota on the development of PD has been the subject of growing interest among researchers. It has been suggested that gut inflammation may be closely associated with pathogenesis in PD, therefore leading to the hypothesis that gut microbiota modulation could play a significant role in this process. Nutrition can influence gut health and alter the risk and progression of PD by altering inflammatory markers. This review provides an overview of recent research that correlates variations in gut microbiota composition between patients with PD and healthy individuals with the impact of certain nutrients and dietary patterns, including the Mediterranean diet, the Western diet, and the ketogenic diet. It explores how these diets influence gut microbiota composition and, consequently, the risk of PD. Last, it examines fecal transplantation and the use of prebiotics, probiotics, or synbiotics as potential therapeutic strategies to balance the gut microbiome, aiming to reduce the risk or delay the progression of PD.

Beyond soluble and insoluble: A comprehensive framework for classifying dietary fibre's health effects

Despite evolving definitions, dietary fibre classifications remain simplistic, often reduced to soluble and insoluble types. This binary system overlooks the complexity of fibre structures and their diverse health effects. Indeed, soluble fibre is not just soluble but has important qualities such as fermentability, attenuating insulin secretion, and lowering serum cholesterol. However, this limited classification fails to account for dietary fibre diversity and predict their full range of physiological effects. This article proposes a holistic classification framework that accounts for different fibre types and can be used to accurately infer their physiological outcomes. This proposed classification framework comprises of five constituents: backbone structure, water-holding-capacity, structural charge, fibre matrix and fermentation rate. This model more accurately captures the structural and functional diversity of dietary fibres, offering a refined approach to predicting their health benefits.

Protective Effect of Dietary Fiber on Blood Pressure and Vascular Dysfunction Through Regulation of Sympathetic Tone and Immune Response in Genetic Hypertension

The mechanisms underlying the antihypertensive effect of dietary fibers remain poorly understood. This study investigates whether dietary fiber supplementation can prevent cardiovascular damage and high blood pressure in a genetic model of neurogenic hypertension. Six-week-old male spontaneously hypertensive rats (SHR) and their respective normotensive control, Wistar Kyoto rats (WKY), were divided into four groups: Untreated WKY, untreated SHR, SHR treated with resistant starch (SHR + RS), and SHR treated with inulin-type fructans (SHR + ITF) for 12 weeks. Additionally, a faecal microbiota transplantation (FMT) experiment was conducted, transferring faecal content from treated SHR donors to recipient SHRs. A diet rich in RS fiber reduced vascular oxidative stress, inflammation, and high blood pressure. These protective effects were associated with a reshaped gut microbiota, leading to increased short-chain fatty acid production, reduced endotoxemia, decreased sympathetic activity, and a restored balance between Th17 and Treg lymphocytes in mesenteric lymph nodes and aorta. Elevated plasma levels of acetate and butyrate in the SHR + RS group correlated with increased expression of aortic GPR41, GRP43 and PPARδ. Conversely, ITF treatment failed to prevent hypertension or endothelial dysfunction in SHR. FMT from the SHR + RS group to recipient SHR partially replicated these beneficial effects. This study highlights the antihypertensive benefits of dietary insoluble RS fiber, which are attributed to enhanced short-chain fatty acids production in the gut. This leads to improved gut permeability, reduced sympathetic tone, and diminished vascular T-cell accumulation. Therefore, dietary interventions with RS fiber may offer promising therapeutic strategies for preventing hypertension.

Effects of fermented bamboo fiber on intestinal health and fecal pollutants in weaned piglets

Introduction

Weaning stress adversely affects piglet growth and development, thereby reducing the economic efficiency of pig farming operations. Furthermore, pig feces are a major source of environmental pollution, underscoring the need for effective strategies to mitigate fecal output at its source.

Methods

This study investigated the effects of dietary supplementation with fermented bamboo fiber (FBF) on growth performance, intestinal barrier integrity, gut microbiota composition, and fecal pollutant levels in weaned piglets. A total of 144 Duroc × Landrace × Yorkshire piglets, weaned at 21 days of age, were randomly assigned to 4 groups, with six replicates per group and 6 piglets per replicate. The control group (CON) received a basal diet, while the three treatment groups were fed the basal diet supplemented with 1, 1.5, and 2% FBF, respectively. The trial lasted 30 days.

Results

The findings revealed that FBF supplementation fortified the intestinal barrier, modulated colonic microbial communities, and decreased fecal pollutant levels. Among the treatment groups, supplementation with 1.5% FBF produced the most significant improvements in piglets' growth performance and intestinal barrier function, as well as the strongest microbial interactions and the greatest reduction in fecal pollutants.

Discussion

These results suggest that FBF supplementation can alleviate weaning stress and mitigate the environmental impact of pig feces, with 1.5% identified as the optimal supplementation level.

Association between dietary index of gut microbiota and constipation in a female population: a cross-sectional study

Objective

To examine the potential association between dietary index of gut microbiota (DI-GM) scores and constipation in adult women in the United States.

Methods

This cross-sectional study used data from adult participants in the 2005-2010 US National Health Survey (NHANES). The missing values in the covariables were filled by multiple interpolation. Multivariate logistic regression models were used to determine the odds ratios (OR) and 95% confidence intervals (CI) for the association between DI-GM and constipation. Subgroup analyses were also performed to examine the possible interactions between DI-GM and constipation.

Results

Of the 7,325 subjects, 887 reported constipations, with a prevalence of 12.1%. After adjustment for multivariate modeling, the DI-GM score was significantly associated with constipation (0.92 [95% CI 0.87-0.96]; p = 0.001). Similar results were found for the association of beneficial gut microbiota score with constipation (OR 0.89 [95% CI 0.84 to 0.95]; p = 0. 001). Subgroup analyses revealed that the relationship between DI-GM scores and constipation remained stable (p > 0.05).

Conclusion

DI-GM was negatively associated with the incidence of constipation in the female population. Clinicians should consider the influence of dietary structure on the treatment of constipation in women. Dietary intervention can be an important strategy for the comprehensive treatment of constipation.

Impact of perioperative dietary fiber intake on gastrointestinal adverse events in adults undergoing abdominal surgery: A systematic review and meta-analysis

BACKGROUND

Patients undergoing abdominal surgery often experience gastrointestinal adverse reactions, which can hinder postoperative recovery. Dietary fiber has potential benefits in regulating gastrointestinal function, but its effectiveness during the perioperative period remains unclear. Therefore, a systematic evaluation of the impact of dietary fiber on postoperative gastrointestinal function in abdominal surgery patients is of significant importance.

AIM

To assess the effects of perioperative dietary fiber-enriched enteral nutrition on postoperative gastrointestinal adverse events in patients undergoing abdominal surgery.

METHODS

Articles published between January 2000 and May 2023 were searched. The occurrence of postoperative gastrointestinal adverse reactions (abdominal infection, intestinal obstruction, diarrhea, nausea and vomiting, anastomotic leak, and time to first flatus) were used as outcomes for systematic review.

RESULTS

A total of 9 randomized controlled trials reporting 833 participants were included. Using meta-analysis, the results showed that perioperative dietary fiber supplement was associated with a lower abdominal infection incidence [risk ratio (RR) = 0.46; 95% confidence interval (CI): 0.26-0.80, P = 0.006] and lower diarrhea incidence (RR = 0.48; 95%CI: 0.32-0.71, P < 0.001), promoted postoperative gastrointestinal function recovery, and shortened the time to first flatus [mean difference (MD) = -0.16; 95%CI: -0.24 to -0.09, P < 0.001]. However, dietary fiber supplementation did not reduce the risk of postoperative intestinal obstruction, nausea and vomiting, or anastomotic leak (P > 0.05).

CONCLUSION

Dietary fiber-rich enteral nutrition can reduce the risk of postoperative abdominal infections and diarrhea, and promote recovery of gastrointestinal function in patients undergoing abdominal surgery, without increasing feeding intolerance such as nausea and vomiting.

Peptide-Rich Yeast Fractions from Brewer's Spent Yeast: A Scalable Fractionation Approach and Their Functional Application in Bakery Products

Brewer's spent yeast (BSY), a significant brewing by-product, poses environmental challenges and opportunities for valorization as a sustainable protein source. This study focuses on transforming BSY into high-value functional ingredients for food applications. A green, sustainable, and scalable process was developed to extract bioactive compounds from BSY at both laboratory and pilot scales, yielding peptide-rich fractions with robust antioxidant properties. These extracts were incorporated into prototype formulations, including protein-enriched crackers, demonstrating their potential as natural, nutritious ingredients. Physicochemical, compositional, and functional characterizations validated their application viability. The antioxidant potential of BSY fractions was confirmed through total phenolic compounds and ABTS and oxygen radical absorbance capacity assays, where the retentate from the 10 kDa ultrafiltration fraction on the pilot scale exhibited superior bioactivity, supporting its selection as the most suitable fraction for food formulations. Additionally, the transition from laboratory to pilot scale revealed slight variations in protein retention and bioactive compound recovery, emphasizing the need for process optimization. These findings highlight BSY's potential to support circular economy practices by reducing waste while enhancing the nutritional and functional value of food products.

Effects of dietary fiber on the composition, function, and symbiotic interactions of intestinal microbiota in pre-weaned calves

Introduction

Dietary fiber plays a crucial role in maintaining gastrointestinal health. However, its protective effects on the intestinal health of calves remain to be fully elucidated. This study aimed to investigate the impact of dietary fiber supplementation on the intestinal microbiota of pre-weaned calves and its potential role in modulating microbial metabolic pathways.

Methods

A randomized controlled trial was conducted, enrolling 135 calves that were randomly assigned into three groups: (1) inulin supplementation, (2) psyllium husk powder (PHP) supplementation, and (3) a control group receiving no dietary fiber. Fecal microbiota samples were collected from calves without diarrhea at five time points (0, 7, 14, 28, and 56 days of age). Metagenomic sequencing was performed to analyze microbial composition and functional pathways. Additionally, a differential analysis of carbohydrate-active enzymes (CAZymes) was performed to evaluate the effect of dietary fiber on carbohydrate metabolism enzyme activity within the intestinal microbiota.

Results

Calves supplemented with dietary fiber exhibited a significant increase in the abundance of Bifidobacterium and Prevotella compared to the control group. These bacterial genera contributed to intestinal protection by modulating secondary bile acid metabolism and flavonoid metabolism pathways. CAZymes differential analysis revealed an increased abundance of carbohydrate metabolism enzymes in response to dietary fiber supplementation, with distinct microbial community compositions observed among different fiber treatments. Notably, at 56 days of age, calves fed PHP harbored intergeneric symbiotic clusters comprising Clostridium, Prevotella, and Bacteroides, suggesting a cooperative microbial network that may contribute to intestinal homeostasis.

Discussion

The findings of this study highlight the beneficial effects of dietary fiber on calf intestinal microbiota, particularly in enhancing microbial diversity and enzymatic activity related to carbohydrate metabolism. The observed microbial symbiosis in PHP-fed calves suggests a potential role in maintaining intestinal homeostasis. These insights provide a theoretical foundation for optimizing dietary interventions to promote gut health in calves during the transition period. Further research is warranted to explore the mechanistic interactions between dietary fiber, gut microbiota, and host health outcomes.

Dietary fiber from burdock root ameliorates functional constipation in aging rats by regulating intestinal motility

Functional constipation is a common gastrointestinal health issue among the aging population. Dietary fiber supplementation is widely recognized as a first-line strategy for constipation. However, the effectiveness of dietary fiber in practical applications remains unsatisfactory, and dietary fibers from different sources are believed to possess varying physiological activities in alleviating constipation. Burdock root is a vegetable rich in dietary fiber. In this study, loperamide was used to induce functional constipation in aged rats. Doses of 3 mg/kg·bw·day and 1.5 mg/kg·bw·day of dietary fiber from burdock root were used to intervene in functional constipation in aged rats. Research indicated that dietary fiber from burdock root enhanced intestinal motility to ameliorate functional constipation in aging rats. This effect may involve several mechanisms, including repairing the intestinal barrier, regulating intestinal hormones, and providing anti-inflammation and antioxidation. Our findings provide a theoretical basis for the potential mechanism by which burdock root dietary fiber can ameliorate functional constipation. It is expected to serve as a natural functional food to combat functional constipation in the aging population.

The mediating role of biological age in the association between dietary index for gut microbiota and sarcopenia

Background

Dietary Index of Gut Microbiota (DI-GM) is a newly proposed comprehensive metric for assessing dietary quality in relation to gut microbiota composition. Alterations in muscle structure are closely linked to DNA methylation-based biological age assessments and individual dietary patterns. However, a systematic investigation of the interrelationships among DI-GM, biological age, and sarcopenia remains lacking. We hypothesize that consuming foods beneficial to the gut microbiota may help mitigate the risk of sarcopenia by slowing the aging process.

Methods

This study analyzed data from NHANES 2007-2018. DI-GM was calculated using two 24-hour dietary recall datasets. Sarcopenia was assessed via dual-energy X-ray absorptiometry (DXA). The association between DI-GM and sarcopenia was evaluated using multivariate logistic regression, subgroup analysis, and restricted cubic splines. This study also investigated the potential mediating effects of three biological age indicators: the Klemera-Doubal Method (KDM), PhenoAge, and Homeostatic Dysregulation (HD).

Results

An increase in DI-GM score was significantly associated with a reduced risk of sarcopenia (OR: 0.87, 95% CI: 0.82-0.94).The risk of sarcopenia was significantly lower in the highest quartile group (Q3) (OR: 0.25, 95% CI: 0.11-0.58). The three biological age-related indicators (KDM, PA, and HD) partially mediated the association between DI-GM and sarcopenia, with PhenoAge showing the highest mediation proportion at 30.6%.

Conclusion

A higher DI-GM score was significantly associated with a reduced risk of sarcopenia. PhenoAge, HD, and KDM demonstrated significant mediating effects, with PhenoAge showing the highest mediation proportion.

The Particle Size of Wheat Bran Dietary Fiber Influences Its Improvement Effects on Constipation

Wheat bran dietary fiber (WBDF) is a potential functional additive to enrich products used for relieving constipation. The purpose of this study was to understand the effects of different particle size ranges (mean sizes of 84.14, 61.74, 37.39, and 22.33 μm) of WBDF on constipation. With the decrease in particle size, its morphology exhibited an increase in fiber fragmentation, larger pore sizes, and the formation of structural faults. The oil-holding capacity (OHC) and swelling capacity (SC) of WBDF were found to change with particle size, with the highest OHC observed at 37.39 μm and the greatest SC at 84.14 μm. Animal experiments demonstrated that the WBDF of smaller particle sizes significantly alleviated loperamide-induced constipation with an increased intestinal propulsion rate, decreased first melanin excretion time, and reduced gastric residual rate. Meanwhile, WBDF samples markedly increased serum MTL and serum AChE levels. Notably, compared with the constipation model (CMNC) group, the small intestinal propulsion rate in the MPS40 group increased by 41.21%, and the gastric residue rate significantly decreased by 19.69%. The improvement in constipation symptoms was most pronounced. Additionally, the abundance of Lactobacillus in the MPS40 group increased by 52.52%, while the relative abundance of Prevotella decreased by 83.55%, and the diversity of the gut microbiota was altered. These findings provide valuable insights into the potential commercial applications of WBDF in fiber-enriched functional foods to support intestinal health.

Metatranscriptomics for Understanding the Microbiome in Food and Nutrition Science

Microbiome science has greatly expanded our understanding of the diverse composition and function of gut microorganisms over the past decades. With its rich microbial composition, the microbiome hosts numerous functionalities essential for metabolizing food ingredients and nutrients, resulting in the production of active metabolites that affect food fermentation or gut health. Most of these processes are mediated by microbial enzymes such as carbohydrate-active enzymes and amino acid metabolism enzymes. Metatranscriptomics enables the capture of active transcripts within the microbiome, providing invaluable functional insights into metabolic activities. Given the inter-kingdom complexity of the microbiome, metatranscriptomics could further elucidate the activities of fungi, archaea, and bacteriophages in the microbial ecosystem. Despite its potential, the application of metatranscriptomics in food and nutrition sciences remains limited but is growing. This review highlights the latest advances in food science (e.g., flavour formation and food enzymology) and nutrition science (e.g., dietary fibres, proteins, minerals, and probiotics), emphasizing the integration of metatranscriptomics with other technologies to address key research questions. Ultimately, metatranscriptomics represents a powerful tool for uncovering the microbiome activity, particularly in relation to active metabolic processes.

Functional Foods and Nutraceuticals in Irritable Bowel Syndrome

Irritable bowel syndrome (IBS) is a common disorder of gut-brain interaction, with a multifactorial pathophysiology involving gut-brain axis dysregulation, visceral hypersensitivity, microbiota imbalance, and immune dysfunction. Traditional IBS management emphasizes dietary modifications and pharmacologic therapies. However, increasing attention has been directed toward functional foods, nutraceuticals, and herbal remedies due to their potential to target IBS pathophysiological mechanisms with favorable safety profiles. This clinical review explores the role of these adjunctive therapies, evaluating evidence from preclinical and clinical studies. Functional foods such as kiwifruit, prunes, and rye bread demonstrate benefits in bowel habit regulation through fiber content and microbiota modulation. Nutraceuticals like peppermint oil, palmitoylethanolamide, and herbal mixtures exhibit anti-inflammatory, antispasmodic, and analgesic effects. Prebiotics provide substrate-driven microbiota changes, although dosage is key, as given their fermentative properties, when used at high dosages, they can exacerbate symptoms in some individuals. Probiotics and postbiotics offer microbiota-based interventions with promising symptom relief in IBS subtypes, although factors for personalized treatment still need to be further elucidated. These strategies highlight a paradigm shift in IBS management, integrating diet-based therapies with evolving nutraceutical options to improve patient outcomes. Despite promising findings, challenges in standardizing definitions, mechanisms, and safety profiles still remain. Rigorous, large-scale trials to validate the therapeutic potential of these interventions are needed, to enhance the benefits of these compounds with an individualized treatment approach.

Nutritional, functional, and microbial qualities of legume-based flour blends processed by SMEs in Zambia and Malawi compared to standard Corn-Soy Blend Plus (CSB +): a cross-sectional study

BACKGROUND

Legumes enhance food security in developing countries, necessitating an understanding of their properties. This study examined the nutritional, functional, and microbial qualities of legume-based flour blends from Small and Medium Enterprises (SMEs) in Malawi and Zambia. SMEs were chosen for their key role in local food production, distribution, and complementary food supply.

METHOD

A total of 36 legume-based flour blend samples were collected using snowball sampling, consisting of 21 samples (7 sets of 3 similar samples) from SMEs in Zambia and 15 samples (5 sets of 3 similar samples) from SMEs in Malawi. Samples were analyzed for proximate composition, energy, iron, and zinc content. The nutritional contributions to the Recommended Dietary Allowances (RDA) for children aged 1-3 years were assessed. Additionally, functional properties such as water-holding and oil-holding capacities were measured. Microbial analysis was performed, and the data were statistically analyzed to determine significance (p ≤ 0.05).

RESULTS

Our findings revealed substantial variability in the nutritional content of these flour blends. Protein content ranged from 9.4% to 41.5%, carbohydrates from 8.1% to 71.3%, crude fat from 2.3% to 26.8%, and crude fiber from 6.2% to 35.2%. Iron and zinc levels also varied significantly, from 2.9 to 21.9 mg/100 g and 2.2 to 5.2 mg/100 g, respectively. These inconsistencies highlight a lack of standardization in nutrient content for blends intended for infant feeding. When prepared as 96 g porridge servings for children aged 1-3 years, the blends provided notable contributions to the Recommended Dietary Allowance (RDA). However, their nutrient levels were generally lower compared to the standard Corn-Soy Blend Plus (CSB +). The flour blends also showed variations in physico-functional properties, and some had microbial loads exceeding 250 cfu/g, reflecting inadequate hygiene practices during processing.

CONCLUSION

To enhance their products, SMEs should ensure that their flour blends meet both nutritional and safety standards while striving to match or surpass the nutrient content of CSB + to remain competitive in the market.

Advancements in the investigation of gut microbiota-based strategies for stroke prevention and treatment

Stroke represents a predominant cause of mortality and disability on a global scale, impacting millions annually and exerting a considerable strain on healthcare systems. The incidence of stroke exhibits regional variability, with ischemic stroke accounting for the majority of occurrences. Post-stroke complications, such as cognitive impairment, motor dysfunction, and recurrent stroke, profoundly affect patients' quality of life. Recent advancements have elucidated the microbiota-gut-brain axis (MGBA), underscoring the complex interplay between gut health and brain function. Dysbiosis, characterized by an imbalance in gut microbiota, is significantly linked to an elevated risk of stroke and unfavorable outcomes. The MGBA plays a crucial role in modulating immune function, neurotransmitter levels, and metabolic byproducts, which may intensify neuroinflammation and impair cerebral health. This review elucidates the role of MGBA in stroke pathophysiology and explores potential gut-targeted therapeutic strategies to reduce stroke risk and promote recovery, including probiotics, prebiotics, pharmacological interventions, and dietary modifications. However, the current prevention and treatment strategies based on intestinal flora still face many problems, such as the large difference of individual intestinal flora, the stability of efficacy, and the long-term safety need to be considered. Further research needs to be strengthened to promote its better application in clinical practice.

Supplementation with Lentil (Lens culinaris) Hull Soluble Dietary Fiber Ameliorates Sodium Dextran Sulfate-Induced Colitis and Behavioral Deficits via the Gut-Brain Axis

In this study, the impact of lentil hull soluble dietary fibers (SDFs) on colitis and behavioral deficits in mice was assessed. Structural characterizations of SDFs confirmed that cellulase-modified soluble dietary fiber exhibited better physicochemical properties: more porous microstructure; similar polysaccharide structure; more stable particle size distribution; higher crystallinity; better adsorption capacity; and lower viscosity. Additionally, we explored its potential cognitive benefits via the gut-brain axis by behavioral tests, histopathology, 16S rRNA sequencing, gas chromatography and metabolomics analysis. The results showed that SDFs significantly improved inflammatory symptoms in colon and brain and cognitive behaviors. LSDF had better efficacy than HSDF. LSDF intervention decreased the harmful bacteria abundance (Bacteroides, Flexispira and Escherichia, etc.) and increased beneficial bacteria abundance (Aggregatibacter and Helicobacter, etc.). LSDF also affected brain metabolites through the sphingolipid metabolism. Spearman correlation analysis showed that there was a positive correlation between harmful bacteria with inflammatory factors (LPS, IL-1β, IL-6, and TNF-α, etc.) and sphingolipid metabolites, while beneficial bacteria were positively correlated with brain-derived neurotrophic factor (BDNF), IL-10, and cognitive behavior. This study highlights the value of SDFs in future diet-based therapeutic strategies targeting gut-brain interactions.

Crucial Roles of Brassinosteroids in Cell Wall Composition and Structure Across Species: New Insights and Biotechnological Applications

Brassinosteroids (BR) are steroidal phytohormones essential for plant growth, development, and stress resistance. They fulfil this role partially by modulating cell wall structure and composition through the control of gene expression involved in primary and secondary cell wall biosynthesis and metabolism. This affects the deposition of cellulose, lignin, and other components, and modifies the inner architecture of the wall, allowing it to adapt to the developmental status and environmental conditions. This review focuses on the effects that BR exerts on the main components of the cell wall, cellulose, hemicellulose, pectin and lignin, in multiple and relevant plant species. We summarize the outcomes that result from modifying cell wall components by altering BR gene expression, applying exogenous BR and utilizing natural variability in BR content and describing new roles of BR in cell wall structure. Additionally, we discuss the potential use of BR to address pressing needs, such as increasing crop yield and quality, enhancing stress resistance and improving wood production through cell wall modulation.

How to Study the Effects of Dietary Lipids on the Small Intestinal Microbiome? Methodological Design and Evaluation of the Human HealThy fAt, haPpy mIcRobiome (TAPIR) Proof-of-Concept Study

Background

Emerging evidence highlights the importance of the small intestinal microbiota in digestion and metabolism, underscoring the challenging need for human studies beyond fecal analyses.

Objective

The TAPIR (acronym of "healthy fat, happy microbiome") proof-of-concept study was primarily designed to confirm the interaction between the small intestinal microbiota and dietary lipids in healthy adults with a challenge test. We also aimed to assess the impact of a plant-based mild-ketogenic preconditioning diet on microbiome composition and function. Here, we comprehensively describe our extensive study protocol and evaluate the study execution.

Methods

Participants consumed an 8-day preconditioning diet, followed by a high-fat shake challenge test on day 9. During this test, fasting and postprandial small intestinal aspirates were collected every 20 min via a naso-intestinal catheter, and blood samples were collected hourly. Participants ingested small intestine aspiration capsules before (day 0), on day 6 of the preconditioning diet, and during the challenge test. Dietary compliance, capsule retrieval, sample collection, stool pattern, and gastrointestinal complaints were monitored to evaluate study execution.

Results

Twenty adults with a mean age of 48 y (19-88 y) and a mean body mass index (BMI) of 24.3 kg/m2 (19.5-30 kg/m2) consumed a preconditioning diet with a 96% compliance. There were no significant changes in gastrointestinal complaints and stool patterns during the study. Mean aspiration capsule retrieval rate was 94.7%, with mean sample weights per timepoint between 84.2 and 95.4 mg and median transit times between 32.8 and 49.3 h. The average success rate of aspirate collection by catheter was 49%, varying significantly between time points.

Conclusion

The dietary intervention was successful and well-tolerated. We sampled in the small intestine with capsules and catheters, each with its own (dis)advantages. The comprehensive description and evaluation of our study execution offer practical insights supporting future study designs in food-microbe interactions in the small intestine.The trial is registered at clinicaltrials.gov as NCT06064266.

The association between dietary fiber intake and osteoarthritis: a cross-sectional study from the 1999-2018 U.S. National Health and Nutrition Examination Survey

OBJECTIVE

The relationship between dietary fiber intake and osteoarthritis (OA) remains unclear. This cross-sectional study, using data from the National Health and Nutrition Examination Survey (NHANES), aimed to examine the association between dietary fiber intake and OA.

METHODS

A cross-sectional analysis was conducted using NHANES data from 1999 to 2018 to assess the association between dietary fiber intake and OA. Univariate and multivariate weighted logistic regression models, along with restricted cubic spline (RCS) curves, were used to evaluate the relationship.

RESULTS

A total of 30,620 participants were included in this study, of whom 1,864 were diagnosed with OA, yielding a prevalence of 5.74%. Multivariate weighted logistic regression revealed a consistent inverse association between dietary fiber intake and OA (OR = 0.99, 95% CI: 0.97-0.99, P = 0.018). When dietary fiber was treated as a categorical variable, the highest quartile of intake (Q4) was associated with a 27% lower risk of OA compared to the lowest quartile (Q1) (OR = 0.73, 95% CI: 0.58-0.92, P = 0.007). The RCS analysis indicated a non-linear association between dietary fiber intake and OA risk (non-linear P = 0.013). The threshold effect interval suggested that dietary fiber intake in the range of 14.4-26.7 g was associated with a reduced risk of OA, while intake above this level did not provide significant additional protection.

CONCLUSION

The findings demonstrate a negative linear association between dietary fiber intake and OA risk. Increasing dietary fiber consumption may reduce the risk of OA, offering potential strategies for its prevention and management. Further studies are needed to confirm these findings.

The Relationship Between Fiber Intake and Gut Bacterial Diversity and Composition During the Third Trimester of Pregnancy

BACKGROUND/OBJECTIVES

High fiber (34-36 g/day) diets are recommended during pregnancy due to inverse associations with constipation and adverse pregnancy health outcomes, including pre-eclampsia and gestational diabetes. However, the mechanism for this protective effect is poorly defined. Fiber may be protective due to its impact on the composition and function of specific bacteria within the pregnancy gut microbiome. The purpose of this analysis was to investigate whether a sub-sample of cohort study participants in their third trimester met daily dietary fiber and vegetable intake recommendations and, in turn, how this impacted bacterial composition and butyrate-producing genes within the gut microbiome.

METHODS

Pregnant participants (n = 52) provided stool samples and survey data, which were used to calculate fiber and vegetable intake. Genomic DNA was extracted from the stool samples, followed by PCR to amplify the V4 region of the 16S rRNA gene. Amplicons were sequenced and mapped to the RDP reference. Quantitative real-time PCR was used to measure the abundance of bacterial genes for butyrate production.

RESULTS

Of the pregnant participants in this sample, 84.7% and 92.3% failed to meet recommendations in the Dietary Guidelines for Americans for dietary fiber and vegetable intake, respectively. All four participants who met the vegetable recommendation were a subset of those who met the fiber recommendation. The participants who met the pregnancy fiber recommendation had gut microbiotas with greater alpha diversity (Shannon and Inverse Simpson) than those who did not. However, there was no association between dietary fiber intake and the abundance of bacterial genes for butyrate production.

CONCLUSIONS

This research suggests that general fiber intake during pregnancy has a modest association with the gut bacterial community. These preliminary results demonstrate a need to improve fiber intake during pregnancy. Further, studies that measure the relationship between dietary intake of specific types of fiber and associations with specific gut bacterial community members and their functions are needed.

Examination of a novel dietary fiber formulation on morphology and nutritional physiology of young male Sprague-Dawley rats fed a high fat diet

Western diets are a public health concern as excess intake of simple sugars and fatty foods, and consequently low consumption of fruits and vegetables, can contribute to obesity and other chronic diseases such as diabetes mellitus, metabolic syndrome, cardiovascular diseases, and cancer. Due to the high prevalence of diseases related to Western diets, the objective of this study was to evaluate whether the inclusion of a novel fiber-rich complex could prevent high fat diet-induced weight gain, adiposity, hyperglycemia, dyslipidemia, and oxidative stress in young male Sprague-Dawley rats, Rattus norvegicus. The novel fiber complex contained a blend of bioactive ingredients: 27% flaxseed, 15.9% wheat bran, 14.8% wheat germ, 10% psyllium, 13.1% brewer's yeast, and 19.2% grapeseed flour. The study included 24 6-week-old rats divided into three groups that were fed either a control diet (C; standard rodent maintenance diet) containing fiber (3.8%g diet); high-fat diet (H) containing Solka Floc cellulose fiber (6.46%g diet); or high-fat diet in which 5% of the diet was replaced with the novel fiber complex (HF) (total fiber: 5%g fiber complex + 6.14%g Solka Floc). Rats in all diet groups gained significant weight during the 6-week feeding period (p < 0.001) consistent with normal growth. Whereas no differences were observed for blood lipids or beta-hydroxybutyrate, consumption of the H diet significantly increased adiposity (p < 0.001), liver triglycerides (p < 0.001), and fasting whole blood glucose concentrations (p < 0.001) in comparison to the C diet. These effects of high fat consumption were not prevented by the inclusion of the novel fiber complex in this experimental design.

Dietary and nutritional interventions for human diseases: their modulatory effects on ferroptosis

A balanced diet is essential for maintaining human health. Increasing evidence suggests that dietary and nutritional interventions contribute to disease management and are associated with reduced healthcare costs and economic burden. Ferroptosis, a novel type of regulated cell death (RCD) driven by lipid peroxidation, has been shown to be involved in various pathological conditions, including diabetes, ischemia/reperfusion (I/R) injury, inflammation-related diseases, and cancer. Therefore, specifically targeting the uncontrolled ferroptosis process may offer new therapeutic opportunities. Of note, certain interventions, such as small-molecule compounds, natural products, herbal medicines, and non-pharmacological approaches, have been reported to prevent and treat multiple human diseases by reversing the dysregulation of ferroptosis. In this review, we present the key molecular mechanisms that regulate ferroptosis. Importantly, interventions targeting ferroptosis are summarized from the perspective of dietary patterns, food and nutrients. By understanding these advances, innovative ideas can be provided for individualized dietary interventions and treatment strategies.

Inclusion of antimicrobial and antioxidant spices into milk candy towards enhancement of nutrient contents and bio-functional activities

Herbs and spices are known for their health benefits and thus, commonly used in foods to enhance taste, flavour and shelf life. This study produced milk candy with medicinal spices, assessed their proximate composition, prebiotic, and antioxidant activities using standard methods. Phenol contents of extracts from Aframomum melegueta (25.40 mg/100g) and Ocimum gratissimum (24.80 mg/100g) were not significantly different (p ≥ 0.05). Extracts from Ocimum gratissimum (5.50 mg/100g), Piper guineense (5.50 mg/100g), Cinnamomum burmannii (5.10 mg/100g), and Trigonella foenum-graecum (5.20 mg/100g) have similar (p ≥ 0.05) terpenoid content. Zones of inhibition displayed by the spices against indicator microorganisms ranged from 5.20 mm to 10.30 mm with MIC values of 50-200 μg/mL. Extracts from Ocimum gratissimum, Aframomum melegueta, and Xylopia aethiopica scavenged 1, 1-diphenyl-2-picrylhydrazyl (DPPH) with similar (p ≥ 0.05) values of 90.6 %, 91.5 %, and 92.5 %, respectively. The crude fibre of milk candy with spices increased from 6.90 to 8.10 % when compared (p ≥ 0.05) to milk candy without spices (3.90 %). Milk candies with Xylopia aethiopica and Zingiber officinale have the same scavenging activity of 65.80 % against DPPH. Milk candy fortified with Cuminum cyminum supported the growth of probiotics; Lactobacillus fermentum with the highest values of 8.30 × 105 cfu/mL and 6.90 × 105 cfu/mL for Lactobacillus acidophilus. Addition of spices to milk candy gain wide acceptance by consumers due to savory. Medicinal herbs and spices can be successfully incorporated into milk products to enhance their bio-functional potentials, and to alleviate the intolerance of individual that are allergic to dairy products.

Influence of Dietary Quality on Neurogenic Bowel Dysfunction in Individuals With Spinal Cord Injury

Background

Neurogenic bowel dysfunction (NBD) occurs in up to 95% of individuals with spinal cord injury (SCI) and negatively impacts the quality of life. Although diet is an important component in the management of NBD, the relationship between diet quality and NBD is understudied in the SCI population.

Objectives

To assess the diet quality of individuals with chronic SCI and explore possible relationships between diet quality, especially fiber, and symptoms of NBD, and to evaluate whether individuals with SCI themselves recognize relationships between dietary intake and NBD symptoms.

Methods

Individuals with chronic SCI, recruited via their rehabilitation center, completed web-based questionnaires and 24-hour dietary recalls regarding the quality and intake of their diet and the severity of NBD. Ten individuals participated in interviews to explore their views on potential relationships between their diet and NBD.

Results

Twenty-eight participants were recruited, of which ten were interviewed. All participants had symptoms of NBD of varying degrees and a low diet quality, but there was no difference between the NBD groups. The more severe NBD group had a lower intake of vegetables and a higher intake of salt. Almost half of the participants interviewed did not report experiencing an association between dietary intake and their NBD.

Conclusions

A low diet quality was observed among individuals with chronic SCI, irrespective of their NBD symptoms. Many participants were unaware of a potential relationship between their diet and NBD. The sample size is insufficient to draw definitive conclusions; however, a potential hypothesis is that those with more severe NBD may consume not enough vegetables and too much salt. Further longitudinal prospective research is required to enhance nutritional guidelines for individuals with SCI and NBD.

Associations between nutrient intake and osteoarthritis based on NHANES 1999 to 2018 cross sectional study

The relationship between nutrient intake and osteoarthritis (OA) remains unclear. This study utilized data from the National Health and Nutrition Examination Survey (NHANES) in a multi-cycle retrospective cohort study to explore the associations between the intake of six nutrients-carbohydrates, dietary fiber, protein, fat, folate, niacin and OA. This study performed a cross-sectional analysis using NHANES data from 1999 to 2018 to investigate the relationship between the intake of six nutrients and OA. Univariate and multivariate weighted logistic regression models, along with restricted cubic splines (RCS), were applied to assess the associations between nutrient intake and OA. A total of 32,484 participants were included in the study, of whom 1864 were diagnosed with OA, resulting in a prevalence rate of 5.74%. Multivariate weighted logistic regression consistently demonstrated that dietary fiber, folic acid, and nicotinic acid intake were negatively associated with the presence of OA, while protein intake exhibited a J-shaped relationship with OA, and carbohydrate or fat intake showed no significant association with OA. Compared with participants in the lowest quartile (Q1), those in the highest quartile (Q4) of dietary fiber, folic acid, and nicotinic acid intake had 27%, 28%, and 33% lower odds of having OA, respectively, after adjusting for potential confounding factors. RCS analysis revealed that dietary fiber and nicotinic acid intake had a nonlinear relationship with the presence of OA, folic acid intake had a linear relationship with OA, and protein intake followed a J-shaped curve with OA. These results suggest that higher intake of dietary fiber, folic acid, and nicotinic acid is associated with a reduced likelihood of OA, while protein intake follows a J-shaped curve, with moderate intake offering the greatest protection. These findings highlight the importance of balancing protein intake and optimizing the consumption of other nutrients for the prevention and management of OA. Further research is needed to confirm these findings and clarify the underlying mechanisms.

Applications of bacterial cellulose in the food industry and its health-promoting potential

Bacterial cellulose (BC) is a naturally occurring biomaterial with a wide range of potential applications in the food industry because of its exceptional mechanical qualities, unique nanofiber structure, high purity, and outstanding biocompatibility. Beyond its physical attributes, BC has gained interest recently due to research demonstrating its potential health benefits as a functional food ingredient. This article examines the many uses of BC in the food business, with a focus on how it may enhance food texture, operate as a bioactive carrier, and have promise in the packaging sector. Further research was done on the health-promoting properties of BC in functional foods, particularly with regard to its functions as a blood glucose regulator, and gastrointestinal health. This review seeks to bring fresh ideas for the study of bioactive components in the food industry by providing a summary of the existing research and demonstrating the possible role of BC in food. It also suggests future paths for research.

Foxtail millet bran dietary fibres foster in vitro beneficial gut microbes and metabolites while suppressing pathobionts

Foxtail millet bran soluble dietary fibre (MBSDF) is a dietary compound with various bioactivities, potentially modulated by the gut microbiota. To elucidate this bioregulatory mechanism, this study focused on the structureal composition and in vitro fermentation characteristics of MBSDF. The results revealed that MBSDF has a molecular weight of 18.26 kDa. The main chain is connected through a glycosidic bond in the form of →4)-α-D-Glcp-(1 → 4)-β-D-Xylp-(1→, being branched by →4, 6)-α-D-Glcp-(1 → O-6 and →3, 4)-β-D-Xylp-(1 → O3 bonds. After 24 h fermentation, the carbohydrate utilisation rate reached 59.15 %, with a decreased molecular weight and monosaccharide composition molar mass ratio. Meanwhile, a increase was observed in the short-chain fatty acid, accompanied by an increased relative abundance of Faecalibacterium, Bifidobacterium and Lactobacillus and suppressed growth of pathogenic Enterococcus. Interestingly, the modulation of gut homeostasis probably occurs via butyrate metabolism pathway. Collectively, MBSDF can selectively regulate the gut microbiota and their metabolites.

An oat fiber intervention for reducing PFAS body burden: A pilot study in male C57Bl/6 J mice

Perfluoroalkyl substances (PFAS) are a major public health concern, in part because several PFAS have elimination half-lives on the order of years and are associated with adverse health outcomes. While PFAS can be transported into bile, their efficient reuptake by intestinal transporter proteins results in minimal fecal elimination. Here, we tested the hypothesis that consumption of oat β-glucan, a dietary supplement known to disrupt the enterohepatic recirculation of bile acids, will reduce PFAS body burdens. Male C57Bl/6 J mice were fed diets based on the "What we eat in America" analysis that were supplemented with inulin or oat β-glucan and exposed via drinking water to a seven PFAS mixture (PFHpA, PFOA, PFNA, Nafion Byproduct-2, PFHxS and PFOS) for 6 weeks. One cohort of mice was euthanized at the end of the exposure, and one cohort continued on the experimental diets for 4 more weeks without additional PFAS exposure. The β-glucan fed mice drank significantly more water than the inulin fed mice, resulting in a significantly higher dose of PFAS. Relative to overall exposure, we observed lower serum concentration trends (p < 0.1) in β-glucan fed mice for PFHpA, PFOA and PFOS. Additionally, β-glucan fed mice had lower adipose:body weight ratios and liver and jejunum triglyceride concentrations. Hepatic mRNA expression of Cyp4a10, Cyp2b10 and Cyp3a11 were elevated in PFAS exposed mice, with only the expression of Cyp3a11 decreasing following depuration. This pilot study generates support for the hypothesis that oat β-glucan supplementation can reduce PFAS body burdens and stimulate healthful effects on lipid homeostasis.

The evolution of nutrition management in children with severe neurological impairment with a focus on cerebral palsy

Nutritional management of children with severe neurological impairment (SNI) is highly complex, and the profile of this population is changing. The aim of this narrative review was to give the reader a broad description of evolution of the nutritional management of children with SNI in a high resource setting. In the last decade, there has been an emphasis on using multiple anthropometric measures to monitor nutritional status in children with SNI, and several attempts at standardising the approach have been made. Tools such as the Feeding and Nutrition Screening Tool, the Subjective Global Nutrition Assessment, the Eating and Drinking Ability Classification System and the Focus on Early Eating and Drinking Swallowing (FEEDS) toolkit have become available. There has been an increased understanding of how the gut microbiome influences gastrointestinal symptoms common in children with SNI, and the use of fibre in the management of these has received attention. A new diagnosis, 'gastrointestinal dystonia', has been defined. The increased use and acceptance of blended food tube feeds has been a major development in the nutritional management of children with SNI, with reported benefits in managing gastrointestinal symptoms. New interventions to support eating and drinking skill development in children with SNI show promise. In conclusion, as the life expectancy of people with SNI increases due to advances in medical and nutrition care, our approach necessitates a view to long-term health and quality of life. This involves balancing adequate nutrition to support growth, development and well-being while avoiding overnutrition and its associated detrimental long-term effects.