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Consolidated Standards of Reporting Trials diagram. 1 Other reasons included an unwillingness to eat all study foods, current participation in other studies, and being over the BMI range at the start date but after signing consent. 2 Unwilling to eat all study foods. RG, refined grain; WG, whole grain.
Source publication
Background:
Observational studies suggest an inverse association between whole-grain (WG) consumption and inflammation. However, evidence from interventional studies is limited, and few studies have included measurements of cell-mediated immunity.Objective:We assessed the effects of diets rich in WGs compared with refined grains (RGs) on immune and...
Context in source publication
Context 1
... these subjects, 319 men and women were screened at the HNRCA for eligibility on the basis of laboratory exclusion criteria. A total of 103 qualified volunteers were enrolled and randomly assigned, and 81 of these individuals completed the study with 40 subjects (25 men and 15 women) in the RG group and 41 subjects (24 men and 17 women) in the WG group ( Figure 2). Of 22 participants who dropped out, 13 individuals dropped out during the run-in phase, and 9 individuals dropped out after random assignment (n = 5 from the RG group, and n = 4 from the WG group) because of personal reasons that were unrelated to the intervention including the need to take anti- biotics, time constraints, family events, no shows, and a di- verticulitis diagnosis by the primary care physician. ...
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The role of the human microbiome in health and disease is increasingly appreciated. We studied the composition of microbial communities present in blood across 192 individuals, including healthy controls and patients with three disorders affecting the brain: schizophrenia, amyotrophic lateral sclerosis, and bipolar disorder. By using high-quality u...
Citations
... Measuring fecal wet and dry weight can help to assess changes in bowel movement frequency and consistency. 4-6 grains of feces were taken from each rat and weighed wet and then dried at 60° C in incubator, and then dry weight was measured (Vanegas et al. 2017). Fecal water weight = ((Predry weight -postdry weight)/Predry weight) X 100. ...
Rationale
Stressors play a critical role in the progression of irritable bowel syndrome (IBS). Heterogenous stress causes alterations in our bowel movements which can further cause anxiety and depression-like symptoms, decreasing the ability of individuals worldwide to function in social, academic, and employment settings.
Objectives
This study was aimed to investigate the effect of orally administered Nigella sativa (0.2 mL/kg b.wt.) seed oil (NSSO) on stress-induced IBS, anxiety, and depression-like symptoms in Wistar rats.
Methods
In the present study, modelling IBS induced anxiety and depression-like symptoms in rodents have been employed to correlate the pathophysiological mechanisms behind this disorder. Moreover, evaluation of ameliorative potential of traditionally used NSSO in IBS was also carried out.
Results
Present investigation indicated that acute stress of 1.5 h daily for 20 days induced hyper cortisol, gastrointestinal (GI) hypermotility, diarrhoea, altered levels of short chain fatty acids (SCFAs), and inflammation which are common symptoms of IBS. Furthermore, depression and anxiety-like symptoms were validated in test groups by various behavioral tests and decreased levels of 5-HT-Transporter mRNA gene expression, which are clear indicators of cognitive impairment.
Conclusions
It is possible that these IBS-like symptoms may have contributed to the pathogenesis of cognitive deficits and depression. However, the anti-oxidative, anti-inflammatory, anti-spasmodic, and possibly the anti-anxiolytic properties of NSSO helped in the mitigation of altered gut-brain axis. Because the concurrent treatment of NSSO alleviated the symptoms of modified GI function and consequently, the anxious & depressive behavior of the animals. Overall, this research explored the protective efficacy of NSSO against stress-induced IBS and depression-like symptoms, shedding light on the potential of this natural compound as a therapeutic option in the field of gastroenterology and psychiatry.
Graphical abstract
... Gut dysbiosis may play a role in the CRC pathogenesis, namely, causing an increased volume of Escherichia coli, Streptococcus bovis, Bacteroides fragilis, and Fusobacterium nucleatum, which can create inflammation or alter the oncogenes and tumor-suppressing genes. However, Vanegas et al. found that the consumption of whole grains instead of refined grains leads to reduced numbers of pro-inflammatory Enterobacteriaceae [88,100,109,120]. Fried meat, as an unhealthy food preparation method, was shown in a study by Gao et al. to reduce gut microbiota diversity and cause alterations in bacteria abundances, including an increase in Veillonella, Dorea, and Dialister, while Flavonifractor and Lachnospiraceae levels were lower [101]. ...
Introduction: The importance of diet in shaping the gut microbiota is well established and may help improve an individual’s overall health. Many other factors, such as genetics, age, exercise, antibiotic therapy, or tobacco use, also play a role in influencing gut microbiota. Aim: This narrative review summarizes how three distinct dietary types (plant-based, Mediterranean, and Western) affect the composition of gut microbiota and the development of non-communicable diseases (NCDs). Methods: A comprehensive literature search was conducted using the PubMed, Web of Science, and Scopus databases, focusing on the keywords “dietary pattern”, “gut microbiota” and “dysbiosis”. Results: Both plant-based and Mediterranean diets have been shown to promote the production of beneficial bacterial metabolites, such as short-chain fatty acids (SCFAs), while simultaneously lowering concentrations of trimethylamine-N-oxide (TMAO), a molecule associated with negative health outcomes. Additionally, they have a positive impact on microbial diversity and therefore are generally considered healthy dietary types. On the other hand, the Western diet is a typical example of an unhealthy nutritional approach leading to an overgrowth of pathogenic bacteria, where TMAO levels rise and SCFA production drops due to gut dysbiosis. Conclusion: The current scientific literature consistently highlights the superiority of plant-based and Mediterranean dietary types over the Western diet in promoting gut health and preventing NCDs. Understanding the influence of diet on gut microbiota modulation may pave the way for novel therapeutic strategies.
... Previous studies have suggested that daily consumption of whole grains may exert specific anti-inflammatory effects by modulating T cell subsets [15,16]. Commonly, whole grains are defined as intact, ground, cracked, or flaked kernels that retain the bran, germ, and endosperm in their natural compounds. ...
... The lack of significant differences suggests that soft wheat flour, regardless of the type, has little effect on the gut microbiome of free-living, healthy adults at the provided dose. This is further supported by two human trials that observed no change in alpha diversity after two 8-week periods or a 6-week period, respectively, of a mixed whole-grain intervention [34,35]. These findings indicate that wheat and its constituents, such as fiber, do not influence the gut microbiota alpha diversity in the healthy adults studied. ...
... Escherichia/Shigella are commonly associated with disease [51]. A previous study showed that Enterobacteriaceae, the family to which Escherichia/Shigella belong, was also depleted following whole-grain consumption [35]. This suggests a potential protective effect of whole wheat on gut health by decreasing the likelihood of overgrowth of these opportunistic pathogenic taxa. ...
Consumption of whole-grain wheat has been associated with positive health outcomes, but it remains unclear whether different types of wheat elicit varying effects on the gut microbiome and intestinal inflammation. The objectives of this research were to investigate the effect of two whole-grain wheat flours versus refined wheat flour on the diversity of the human gut microbiota, as well as on butyrate production capacity and gastrointestinal inflammation, using one-week dietary interventions. For this study, 28 participants were recruited, with ages ranging from 18 to 55 years and a mean BMI of 26.0 kg/m2. For four weeks, participants were provided 80 g daily servings of different wheat crackers: Week A was a run-in period of crackers made from soft white wheat flour, Week B crackers were whole-grain soft white wheat flour, Week C crackers were a wash-out period identical to Week A, and Week D crackers were whole-grain soft red wheat flour. At the end of each week, participants provided fecal samples that were analyzed for markers of intestinal inflammation, including lipocalin and calprotectin, using enzyme-linked immunosorbent assays and quantitative real-time PCR. The primary outcome, gut bacterial community alpha and beta diversity, was similar across timepoints. Three taxa significantly differed in abundance following both whole-grain wheat flour interventions: Escherichia/Shigella and Acidaminococcus were significantly depleted, and Lachnospiraceae NK4A136 group was enriched. Secondary outcomes determined that protein markers of intestinal inflammation and genes related to putative butyrate production capacity were similar throughout the study period, with no significant changes. Lipocalin concentrations ranged from 14.8 to 22.6 ng/mL while calprotectin ranged from 33.2 to 62.5 ng/mL across all 4 weeks. The addition of wheat crackers to the adult human subjects’ usual diet had a minimal impact on their gastrointestinal inflammation or the gut microbiota.
... Participants who consumed a diet rich in whole grains, such as oats and barley, showed a significant increase in the abundance of beneficial gut bacteria, particularly Bifidobacterium and Lactobacillus. In contrast, those who consumed refined grains exhibited a decrease in microbial diversity and a reduction in the production of short-chain fatty acids (SCFAs), which are crucial for maintaining gut health and reducing inflammation [52]. ...
The human gastrointestinal tract hosts a complex and dynamic community of microorganisms known as the gut microbiota, which play a pivotal role in numerous physiological processes, including digestion, metabolism, and immune function. Recent research has highlighted the significant impact of diet on the gut microbiota composition and functionality, and the consequential effects on host health. Concurrently, there is growing evidence linking the gut microbiota to inflammation, a key factor in many chronic diseases such as inflammatory bowel disease (IBD), obesity, diabetes, and cardiovascular diseases (CVDs). This review explores how dietary components influence the gut microbiota composition, how these microbial changes affect inflammatory pathways, and the therapeutic implications of modulating this axis for chronic inflammatory disease prevention and management. Beneficial dietary patterns, such as the Mediterranean diet (MD) and plant-based diets, promote a diverse and balanced gut microbiota composition, supporting anti-inflammatory pathways. Conversely, the Western diet (WD), high in saturated fats and refined sugars, is associated with dysbiosis and increased inflammation. With all the links between the three variables considered, this review attempts to offer a thorough examination of the triangle formed by inflammation, the gut microbiota, and food.
... Whole grains have potential value in weight control as they are rich in dietary fiber, promote satiety, slow gastric emptying, and appetite control, and have a low energy density [12]. In addition, whole grains can regulate the gut microbiota and improve the body's inflammatory state, which is beneficial to weight control [13,14]. Epidemiological investigations and clinical trials have explored the relationship between the consumption of whole grains and obesity. ...
Existing research shows an inconsistent correlation between whole-grain intake and obesity risk, with limited study on the dose–response relationship. Here, we aimed to examine this association and dose–response relationship among U.S. adults who participated in a NHANES (2003–2018). The intake of whole grain was collected and calculated from two rounds of 24 h dietary recall. Obesity was categorized based on body mass index (BMI) and waist circumference (WC). Weighted multivariable logistic regression models were used to calculate the odds of obesity according to whole-grain intake, and the dose–response relationship was modeled by restricted cubic spline regression. Among the 27,862 participants, 38.3% had general obesity, while 58.3% had abdominal obesity. After multivariate adjustment of potential confounders, the participants in the highest quintile of whole-grain intake had a lower prevalence of general obesity (OR 0.79; 95% CI 0.72–0.88) and abdominal obesity (OR 0.80; 95% CI 0.73–0.89) compared with those in the lowest category. Spline regression showed an inversely linear dose–response association between whole-grain intake and the prevalence of general obesity and abdominal obesity. In conclusion, a higher whole-grain intake was associated with lower odds of obesity, both general and abdominal. Our findings highlight the importance of increasing the whole-grain intake to prevent and manage obesity.
... Fruits and vegetables contain high levels of potassium, antioxidants, phytochemicals, and dietary fiber; therefore, reduce the incidence of cardiovascular disease and its risk factors 22 . It is widely believed that the consumption of a high-fiber diet promotes bacterial diversity, increasing beneficial bacteria while decreasing potentially pathogenic bacteria, and thus, the gut microbiota, as well as immune and inflammatory markers 23 . Therefore, a high-fiber diet may stimulate the production of anti-inflammatory cytokines in the gut and reduce post-stroke brain damage. ...
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.
... Compare with healthy adults consumption with refined grains, whole grains diet for 6-wk has modest positive effect on gut microbiota, short-chain fatty acids (SCFAs), effector memory T cells, and the acute innate immune response (Vanegas et al., 2017). Those results suggest that consumption of common whole grains such as whole wheat, barley, oats, brown rice, buckwheat, sorghum, millet and quinoa exerts benefit on health promotion. ...
Osteoporosis is a chronic systemic skeletal disease that affects postmenopausal women and older men, and is characterized by the destruction of bone tissue microstructure, reduced bone content, and a tendency to fracture. Nutrients provided by food are necessary for human survival, and at the same time, the various components of food act back on the human body, affecting its health status. Recent studies have shown that whole grain nutrition is beneficial in relieving osteoporosis and improving bone health. This review focuses on the beneficial effects of dietary pattern including whole grains on bone mineral density and the classical mechanisms of whole grains enrich diet in regulating bone resorption and inhibiting bone formation. Whole grain nutritional interventions might offer new possibilities for the prevention and treatment of osteoporosis.
... Plant-based diet ↑GMB diversity (190)(191)(192) ↑putative beneficial bacteria, including fiber-fermenters/ SCFA-and butyrate-producers (193)(194)(195)(196)(197)) (e.g. Firmicutes, Bifidobacterium) ↓putative pathogenic taxa (102,196) (e.g. ...
... Proteobacteria, Bacteroidetes) ↓inflammatory metabolites/cytokines (191,(196)(197)(198)(199) ↓LPS, SBAs ↓IL-6, IL-2, TNF-a ↓triglycerides (200) ↑anti-inflammatory compounds (201,202) (e.g. flavonoids, urolithins) ↑SCFAs (193)(194)(195)203) (e.g. butyrate) ↑IFN-g secretion (196) ↑IL-10, TLR2, and/or TLR4-expressing DCs (204) ↑epithelial barrier function (196) ↓fecal + intestinal pH (205) ↓colorectal proliferation (196) ↓dyslipidemia (102) High fiber ↑GMB diversity (57, 83,206) ↑putative health-promoting bacteria (194,207) (e.g. ...
... flavonoids, urolithins) ↑SCFAs (193)(194)(195)203) (e.g. butyrate) ↑IFN-g secretion (196) ↑IL-10, TLR2, and/or TLR4-expressing DCs (204) ↑epithelial barrier function (196) ↓fecal + intestinal pH (205) ↓colorectal proliferation (196) ↓dyslipidemia (102) High fiber ↑GMB diversity (57, 83,206) ↑putative health-promoting bacteria (194,207) (e.g. fiber-fermenting Firmicutes, Bifidobacterium, F. prausnitzii, A. muciniphila, Roseburia spp.) ↓pathogenic bacteria (208,209) (e.g. ...
The gut microbiome (GMB) plays a substantial role in human health and disease. From affecting gut barrier integrity to promoting immune cell differentiation, the GMB is capable of shaping host immunity and thus oncogenesis and anti-cancer therapeutic response, particularly with immunotherapy. Dietary patterns and components are key determinants of GMB composition, supporting the investigation of the diet-microbiome-immunity axis as a potential avenue to enhance immunotherapy response in cancer patients. As such, this review will discuss the role of the GMB and diet on anti-cancer immunity. We demonstrate that diet affects anti-cancer immunity through both GMB-independent and GMB-mediated mechanisms, and that different diet patterns mold the GMB’s functional and taxonomic composition in distinctive ways. Dietary modulation therefore shows promise as an intervention for improving cancer outcome; however, further and more extensive research in human cancer populations is needed.
... Baxter et al. demonstrated that potato starch greatly increased total SCFAs including butyrate, with an increase in the relative abundance of Bifidobacteria [103]. Intake of whole grains (40 g/d of fiber) increased the abundance of SCFA-producing genera Lanchnospira and Roseburia compared to refined grain [104]. It is also recommended that athletes supplement their diets with oligosaccharides such as galacto-oligosaccharides and fructose oligosaccharides, which can promote beneficial intestinal metabolism by increasing the intake of plant foods (such as cereals, legumes, vegetables, and fruits) [105]. ...
Numerous research studies have shown that moderate physical exercise exerts positive effects on gastrointestinal tract health and increases the variety and relative number of beneficial microorganisms in the intestinal microbiota. Increasingly, studies have shown that the gut microbiota is critical for energy metabolism, immunological response, oxidative stress, skeletal muscle metabolism, and the regulation of the neuroendocrine system, which are significant for the physiological function of exercise. Dietary modulation targeting the gut microbiota is an effective prescription for improving exercise performance and alleviating exercise fatigue. This article discusses the connection between exercise and the makeup of the gut microbiota, as well as the detrimental effects of excessive exercise on gut health. Herein, we elaborate on the possible mechanism of the gut microbiota in improving exercise performance, which involves enhancing skeletal muscle function, reducing oxidative stress, and regulating the neuroendocrine system. The effects of dietary nutrition strategies and probiotic supplementation on exercise from the perspective of the gut microbiota are also discussed in this paper. A deeper understanding of the potential mechanism by which the gut microbiota exerts positive effects on exercise and dietary nutrition recommendations targeting the gut microbiota is significant for improving exercise performance. However, further investigation is required to fully comprehend the intricate mechanisms at work.
