Dietary Fiber Consumption Research Articles

Higher dietary fiber intake associated with better survival in male but not female cancer patients: Evidence from National Health and Nutrition Examination Survey 1999–2014

ObjectivesRecent studies have found that dietary fiber improves prognosis in cancer patients. However, few subgroup analyses exist. Subgroups can differ greatly in terms of different factors such as dietary intake, lifestyle, and sex. It is unclear whether fiber benefits all of the subgroups equally. In this study, we examined differences in dietary fiber consumption and cancer mortality between subgroups, including sex. MethodsThis trial was conducted using eight consecutive National Health and Nutrition Examination Surveys (NHANESs) cycles data between 1999 and 2014. Subgroup analyses were used to investigate the results and heterogeneity within subgroups. Survival analysis was performed using the Cox proportional hazard model and Kaplan-Meier curves. Multivariable Cox regression models and restricted cubic spline analysis were applied to examine the association between dietary fiber intake and mortality. ResultsIn total, 3504 cases were included in this study. Among the participants, the mean age (SD) was 65.5 (15.7) y and 1657 (47.3%) of the participants were men. Subgroup analysis found that men differed significantly from women (P for interaction < 0.001). We found no significant differences in the other subgroups (all P for interaction > 0.05). During an average follow-up of 6.8 y, 342 cancer deaths were recorded. The Cox regression models found that fiber consumption was associated with a lower cancer mortality rate in men (model I: hazard ratio [HR] = 0.60; 95% CI, 0.50–0.72; model II: HR = 0.60; 95% CI, 0.47–0.75; and model III: HR = 0.61; 95% CI, 0.48–0.77). However, there was no relationship between fiber consumption and cancer mortality in women (model I: HR = 1.06; 95% CI, 0.88–1.28; model II: HR = 1.03; 95% CI, 0.84–1.26; and model III: HR = 1.04; 95% CI, 0.87–1.50). The Kaplan-Meier curve illustrates that male patients who consumed higher levels of dietary fiber survived significantly longer than those who consumed lower levels of fiber (P < 0.001). However, there were no significant differences between the two groups in terms of female patients (P = 0.84). A dose-response analysis found an L-shaped relationship between fiber intake and mortality among men. ConclusionsThis study found that higher dietary fiber intake was only associated with better survival in male cancer patients, not in female cancer patients. Sex differences between dietary fiber intake and cancer mortality were observed.

Dietary Fiber Increases Oxidative Metabolism in Colonocytes but Not in Distal Small Intestinal Enterocytes Isolated from Rats

Colonocyte and distal small intestinal enterocyte metabolism was studied in rats fed either an elemental diet or an elemental diet supplemented with 30% mixed dietary fiber for 14 d. Cells were incubated in RPMI 1640 culture media containing 14C-labeled glutamine (1 mmol/L), glucose (11 mmol/L), and short-chain fatty acids: acetate, propionate and butyrate (5 mmol/L). Substrate oxidation and product formation were measured. Colonocytes from the fiber-fed group had 22–51% higher oxidation rates than the elementalfed group for all substrates tested. The group consuming the fiber diet had 28% less glutamate formation from glutamine by isolated colonocytes than the group consuming the elemental diet. Enterocyte acetate oxidation and lactate formation rates were lower (60 and 30%) in the fiber-fed animals vs. the elemental-fed group. Including short-chain fatty acids and ketone bodies in incubation media differentially affected acetate, glutamine and glucose metabolism in isolated intestinal cells, depending on segment and diet. Short-chain fatty acid and glucose oxidation rates were higher for colonocytes than enterocytes and glutamate formation was greater in enterocytes than colonocytes. Fiber consumption increased this segmental disparity. This study demonstrates that dietary fiber consumption increases substrate oxidation by isolated colonocytes but not distal small intestinal enterocytes.

The Role of Dietary Fiber or Prebiotics in Atopic Dermatitis

Introduction: Atopic Dermatitis (AD) is a chronic inflammatory skin condition with itchy eczematous lesions, mostly found in children, and may affect a patient’s quality of life. Individuals with AD were found to have dysbiosis of gut microbial, which may alter the immunologic tolerance of mucosa, causing inflammation and affecting skin conditions. Dietary fiber or prebiotics consumption may have a role in reversing dysbiosis and may affect AD. In this literature review, the authors would like to further explore the role of dietary fiber or prebiotics in the prevention and severity of AD/&#x0D; Methods: Relevant literature research was conducted in several sources: Pubmed, EBSCOHOST, Proquest, and Google Scholar, using keywords “atopic dermatitis, atopic eczema, dietary fiber, prebiotic, nutrition.” Studies published within the last 10 years were included.&#x0D; Discussions: Dietary fiber, particularly soluble fibers and those which can be fermented by gut bacteria (including prebiotics), plays a role in maintaining homeostasis of normal gut flora by producing SCFA, which increases the gut barrier, has anti-inflammatory properties, balances Th1/Th2 ratio, increases lymphocytes in gut-associated lymphoid tissues (GALT) system, and increases secretion of intestinal IgA. The role of dietary fiber/prebiotics in the prevention or decreasing rate of AD is still a matter of debate. Several studies showed no effect or correlation of prebiotic supplementation in decreasing the AD rate in pregnant women or babies with a high risk of atopy. On the other hand, several studies on prebiotic supplementation for babies and children have shown the benefits of prebiotic supplementation in preventing allergies (AD, rhinoconjunctivitis, and urticaria).&#x0D; Conclusion: The role of dietary fiber/prebiotics in preventing or treating AD is still a matter of debate. Different study results make it difficult to conclude the clinical effect of prebiotics in allergy prevention, particularly AD. This may be caused by the heterogeneous studies and the limited number of studies on humans. Further studies (RCT) involving large-scale respondents are needed to define the effects of prebiotic supplementation in the prevention or alternative therapy for AD.

The Influence of Metabolic Factors and Diet on Fertility

Infertility is a disease globally affecting 20-30% of the reproductive age female population. However, in up to 50% on recorded cases, problems with infertility are ascribed to men; therefore, it is important to popularize healthy eating also in this group. During the last decade, it has been observed that society's lifestyle changed drastically: reduced energy expenditure in physical activity per day, increased consumption of hypercaloric and high-glycemic-index foods with high content of trans fats, and reduced consumption of dietary fiber, which negatively affects fertility. Increasing evidence points to a link between diet and fertility. It is becoming clear that well-planned nutrition can also contribute to the effectiveness of ART. The low-GI plant-based diet appears to have a positive effect, especially when it is based on Mediterranean dietary patterns: rich in antioxidants, vegetable protein, fiber, MUFA fatty acids, omega-3, vitamins, and minerals. Importantly, this diet has been shown to protect against chronic diseases associated with oxidative stress, which also translates into pregnancy success. As lifestyle and nutrition seem to be important factors affecting fertility, it is worth expanding knowledge in this regard among couples trying to conceive a child.

A Mediterranean diet is associated with improved total antioxidant content of human breast milk and infant urine

BackgroundThe composition of breast milk (BM) is dynamic and can be influenced by maternal variables that include the diet and nutritional status. This study examined the association between maternal adherence to a Mediterranean diet (MedDiet) and total antioxidant content of BM and infant urine.MethodsWe collected 350 BM samples from mothers and urine samples from their infants. The dietary intakes of the mothers were recorded using a validated 65 items-food frequency questionnaire (FFQ). The total antioxidant status of the samples was assessed using the ferric reducing/antioxidant power (FRAP), the 1, 1-diphenyl-2-picrylhydrazyl (DPPH), thiobarbituric acid reactive substances (TBARS), and thiol quantification assays. Milk protein, calcium, and triglyceride (TG) were also determined using standard biochemical kits.ResultsSubjects with the highest MedDiet scores were among the women in the highest tertile (T3) for consumption of dietary fiber, fruits, vegetables, nuts, legumes, and seeds, low-fat dairy, whole grains, and the lowest consumption of red meat, sweetened beverages, and sodium, compared to women in the first tertile (T1) with the lowest MedDiet scores. After adjustment for potential confounders, the individuals in the highest tertile for MedDiet score had a significantly higher level of milk DPPH, and infant urinary DPPH than the lowest tertile and had a significantly higher level of milk protein, FRAP and infant urinary FRAP compared to the T2 (P < 0.05). In addition, the mothers in the T3 for the MedDiet pattern had a significantly lower level of milk TG compared to those within the T1 (P < 0.05).ConclusionOur findings show that a high maternal adherence to a MedDiet can affect BM composition and their infants' urine.

DEVELOPMENT OF PAPAYA PEEL FLOUR BASED CHAPATTI AND EVALUATION OF ITS QUALITY

Consumption of natural bioactive compounds and dietary fibre offers health benefits and protection against various diseases .The focus of this research was to develop papaya peel flour from raw papaya and utilizing the papaya peel flour for the development of value added chapatti. Fresh papaya was blanched, peeled, cut into small pieces, further washed and treated with sanitizer, tray dried and finally grinded to powder form. Prepared papaya peel flour was evaluated for chemical analysis. In the present study the moisture (%), ash (%), acidity, fat (%), insoluble solid(%),soluble solid(%), protein content(%), vitamin C, total fibre, total carbohydrate and antioxidant content of papaya peel flour were estimated as 13.63%, 5.25%, 163% ,1%, 80%, 20%, 8.64%,22I.U,33.5%,38.88% and 514.6mg/100gm respectively. Papaya peel flour fortified chapatti were formulated by incorporating 5%, 7.5% and 10% papaya peel flour with ordinary flour in the present investigation. Experimental result revealed 5% peel flour formulated chapatti gives the best results in terms of physicochemical quality. The physicochemical and nutritional quality parameters viz. moisture(%), ash(%), acidity, fat(%),vitamin C, insoluble solid (%),soluble solid(%),protein content(%),total fibre, total carbohydrate and antioxidant content of all fortified varieties of chapatti were determined. The best result obtained for 5% papaya peel fortified chapatti and was determined as 10.35%, 4.5%, 0.02%, 15.4%, .31U, 85%, 15%,9.3%,.017%,60.43% and 9gm/100gm respectively. Now the experimental result revealed that papaya peel flour fortified chapatti contains significant amount of protein and antioxidant in comparison to its ordinary counterpart which improves its nutritional characteristics. Sensory evaluations of all fortified varieties were also carried out and it was found that 5% papaya peel flour blend for chapatti formulation was acceptable. Therefore 5% papaya peel flour based formulated chapatti proves enhanced nutritional properties, physicochemical characteristics and organoleptic attributes.

South Asian Housewives; Are We Concerned Enough on Their Health?

Although South Asian females are known to be empowered with abilities and willingness to involve in different careers, the number of ‘housewives’ in the region is still high. That is mainly due to one redeeming quality of majority among the regional females; the greater concern towards their family and children. With such commitments and with recent changes of lifestyles and social values in South Asian food cultures, it was doubtful whether they are concerning on their own health and nutritional needs adequately.&#x0D; To assess this scenario, a study was designed to determine whether the stipulated and such other reasons have an impact to daily nutrient intake of the individuals in the mentioned social segment, who represent the basement of the South Asian family system. Considering an age range between 20–55 years, 800 housewives were selected in Sri Lanka, by disproportionate stratified random sampling. Selected individuals were interviewed using a structured questionnaire, especially to assess their daily food combinations and their consumed portion sizes. Frequently consumed quantitative meal combinations were then chemically analyzed for their macronutrient compositions. Obtained results were compared with world Health organizations’ (WHO) Reference Dietary Intake (RDI) levels of nutrients. The results reveal of significantly (p&lt;0.05) higher daily fat (65.3 ±5.6 g/day) and protein (86.7 ±4.5 g/day) intakes than WHO recommendation levels. However, comparatively lower, but non-significant (p&gt;0.05) daily consumption of dietary fiber (34.3 ±3.3 g/day) levels by selected participants was observed. Digestible carbohydrate intake levels (302.1 ±22.8 g/day) were significantly (p&lt;0.05) higher than reference levels. This indicates of a considerable risk for many individuals in the concerned social segment, of having non-communicable diseases such as diabetes mellitus and hyperlipidemia due to over-nutrition of “calorie generating macronutrients”.

Association of dietary fiber with subjective sleep quality in hemodialysis patients: a cross-sectional study in China

Background Poor sleep quality is a common problem among hemodialysis (HD) patients. Dietary fiber is a key component of a healthy diet and is beneficial for a variety of health outcomes; however, evidence of an association between dietary fiber consumption and subjective sleep quality has not been established among HD patients. Therefore, we determined the association between dietary fiber consumption and the subjective sleep quality in Chinese maintenance HD patients, taking into account fiber type and source. Methods Dietary intake was assessed with a validated food frequency questionnaire in a cross-sectional study including 741 maintenance HD patients between December 2021 and January 2022. The daily intake of dietary fiber was categorized into three groups. The lowest tertile was used as the reference category. Sleep quality of patients was accurately calculated using the Pittsburgh sleep quality index standard questionnaire. Multivariable logistic regression model and restricted cubic spline analysis were performed to assess the relationship between dietary fiber consumption and poor sleep quality. Results Compared with the lowest tertile group of dietary fiber intake, the highest tertile group had a lower prevalence of poor sleep quality. After adjustment for potential confounders, a higher intake of total dietary fiber (ORtertile 3 (T3) to tertile 1 (T1)= 0.51, 95% CI: 0.31–0.85), total insoluble dietary fiber (ORT3 to T1 =0.54, 95% CI: 0.33–0.89), and soluble dietary fiber in vegetables (ORT3 to T1 =0.61, 95% CI: 0.40–0.93) were associated with a lower prevalence of poor sleep quality. Furthermore, significant linear trends were also observed (p < 0.05). No significant interactions were observed in subgroup analyses. Conclusion A higher intake of dietary fiber was inversely associated with the poor sleep quality. These findings support the current recommendations that dietary fiber is essential for health and well-being.

Grain, Gluten, and Dietary Fiber Intake Influence Gut Microbial Diversity: Data from the Food and Microbiome Longitudinal Investigation.

Regular consumption of whole grains and dietary fiber was associated with greater abundance of gut bacteria that may lower risk of colorectal cancer. Further research on the association of refined grains and gluten with gut microbial composition is needed to understand their roles in health and disease.

Dietary fiber intake and non-alcoholic fatty liver disease: The mediating role of obesity.

Dietary pattern rich in fiber is negatively associated with the risk of non-alcoholic fatty liver disease (NAFLD). Meanwhile, obesity is a known predisposing factor for NAFLD. Nutrient-focused research can enhance the mechanistic understanding of dietary effects. We thus hypothesized that higher dietary fiber intake was associated with lower risk of NAFLD through the mediating role of obesity. In this nationwide cross-sectional study, dietary fiber was surveyed using two 24-h recalls. NAFLD and clinically significant fibrosis (CSF) were determined by vibration-controlled transient elastography. Multivariable logistic and linear regression were applied to investigate the association of dietary fiber with NAFLD, CSF, and liver function parameters. We used counterfactual-based mediation analysis to estimate the direct and indirect effect of dietary fiber on NAFLD. Of the 3,974 participants, ~36.86% and 7.78% of participants were diagnosed with NAFLD and CSF. Compared with participants among the lowest tertile, the highest tertile of dietary fiber consumption was associated with lower odds of NAFLD (OR = 0.81; 95% CI: 0.66-0.98; P overall = 0.019). Dietary fiber intake appeared to be linked with lower odds of CSF (OR Tertile3vs.Tertile1 = 0.81; 95% CI: 0.58-1.14; P overall = 0.107). Mediation analysis showed that obesity fully mediated the association of dietary fiber with NAFLD. Dietary fiber was associated with improved hepatic parameters. The findings indicated that increasing dietary fiber intake could confer a greater benefit to protect against NAFLD. Translating these findings regarding dietary fiber into dietary advice might be an attractive strategy for NAFLD prevention.

Sensory Profile, Consumers’ Perception and Liking of Wheat–Rye Bread Fortified with Dietary Fibre

Evidence of global dietary fibre (DF) deficits provides impetus for research to develop new food products and reformulate commonly consumed foods to enable the transition to more healthy diets. The main aim of the study was to evaluate the sensory properties and consumers’ perception, liking, and willingness to buy wheat–rye bread fortified with DF. The study combined expert sensory profiling with consumers evaluation of DF fortified bread in blind and informed conditions. A sensory-trained panel evaluated six samples of bread with flour replaced by 0%, 4%, 8%, 12%, 16%, and 20% with oat DF using 29 pre-identified attributes. A consumer panel (n = 300) evaluated bread samples in blind condition for liking and perception of healthiness, naturalness, and attractiveness and willingness to buy (WTB). Consumers were also asked to indicate the maximum price they were willing to pay for a standard bread of 700 g. In the informed condition, consumers evaluated the 0%, 8%, 12% oat DF samples labelled with either nutritional or health related claims using the same attributes as in blind condition including visual liking. The results of profiling revealed that replacement of flour with oat DF influenced intensity of several attributes related to different modalities. Results of the consumer studies showed that replacement of flour up to 20% with oat DF did not adversely affect consumers’ acceptance and willingness to buy wheat–rye breads. The mean values for bread samples labelled with information related to positive health outcomes of DF consumption were not significantly different from those with nutritional claims only. Combining sensory profiling with consumers acceptance studies gives valuable insights for consumer led new product development. The fortification of staple foods like bread with dietary fibre seems like a promising avenue, but other sources of fibre should also be considered in bread fortification to enhance health-related properties and prevent food waste.

Evidence for Redefining Dietary Fiber

There are currently three macronutrients recognized within the field of dietetics due to their gram quantity intake and requirement for human health; this includes proteins, fats, and carbohydrates. Dietary Fiber, however, is not considered to be an independent macronutrient despite its gram quantity intake and requirement for human health. Additionally, Dietary Fiber is a net-zero energy yielding nutrient unlike other carbohydrates. Although Dietary Fiber should remain chemically categorized as a carbohydrate, for the purposes of dietetic prescription and education, Dietary Fiber should be redefined as the fourth macronutrient. This definition shift would illustrate both the importance and complexity of this macronutrient and may yield an increase in Dietary Fiber consumption and relevant research.

Genome-Wide Association Study of Arabinoxylan Content from a 562 Hexaploid Wheat Collection

The selection of wheat varieties with high arabinoxylan (AX) levels could effectively improve the daily consumption of dietary fiber. However, studies on the selection of markers for AX levels are scarce. This study analyzed AX levels in 562 wheat genotypes collected from 46 countries using a GWAS with the BLINK model in the GAPIT3. Wheat genotypes were classified into eight subpopulations that exhibited high genetic differentiation based on 31,926 SNP loci. Eight candidate genes were identified, among which those encoding F-box domain-containing proteins, disease resistance protein RPM1, and bZIP transcription factor 29 highly correlated with AX levels. The AX level was higher in the adenine allele than in the guanine alleles of these genes in the wheat collection. In addition, the AX level was approximately 10% higher in 3 adenine combinations than 2 guanine, 1 adenine, and 3 guanine combinations in genotypes of three genes (F-box domain-containing proteins, RPM1, and bZIP transcription factor 29). The adenine allele, present in 97.46% of AX-95086356 SNP, exhibited a high correlation with AX levels following classification by country. Notably, the East Asian wheat genotypes contain high adenine alleles in three genes. These results highlight the potential of these three SNPs to serve as selectable markers for high AX content.

Consumption of ultra- and non-ultra-processed foods of individuals with normal-weight obesity.

The normal-weight obesity (NWO) is highly associated with an increased risk for chronic non-communicable diseases and intricately linked to diet quality. Therefore, we assessed the consumption of ultra-processed and non-ultraprocessed foods of 224 Brazilian adults with NWO (n 159) and without NWO (n 65, non-NWO) in a cross-sectional study. For that, three dietary recalls were applied and categorised according to the NOVA classification. Individuals with NWO showed lower energy intake from the 'fresh or minimally processed food' group, specifically for rice (P = 0⋅037), beans (P = 0⋅002) and fruits (P = 0⋅026), as well as lower consumption of dietary fibre (P < 0⋅05) compared with non-NWO subjects. Total consumption of ultra-processed foods did not differ between groups; however, individuals with NWO had a higher energy intake from processed meats compared with the non-NWO group (54⋅1 ± 73⋅5 × 32⋅5 ± 50⋅8 kcal; P = 0⋅023). Energy and added sugar from ultra-processed foods (OR 1⋅02, CI 95 % 1⋅00-1⋅04, P = 0⋅0100) and total fat from non-ultra-processed foods (OR 1⋅09, CI 95 % 1⋅01-1⋅18; P = 0⋅0100) were associated with the presence of NWO. In conclusion, non-NWO individuals consumed more non-ultra-processed foods compared with the NWO group. Overall, there were no differences in the consumption of ultra-processed foods between the two groups. Important associations between food compounds and the presence of NWO were observed, emphasising the importance of fresh and minimally processed foods as the basis of the diet.

The association between gut-health promoting diet and depression: A mediation analysis

BackgroundRecent research has highlighted the relevance of a gut-health promoting diet as a possible treatment and prevention for depression. A dietary pattern with consumption of fermented food and high consumption of dietary fiber can promote gut health, physical health, and might even improve mental health. This study aimed to investigate the interrelationship among diet, physical health, and depression. MethodsThis study used a nationally representative sample (N = 16,572) from the National Health and Nutrition Examination Survey (2011–2018). Dietary information was collected by dietary recall interviews. Depression was assessed by the 9-item Patient Health Questionnaire. Subjective physical health was indicated by self-reported Body Mass Index (BMI). Objective physical health was indicated by BMI measured by trained health technicians. Path analysis was used to test the association between diet and depression, and the mediating roles of self-reported BMI and BMI measured by technicians. ResultsConsumption of probiotic foods and higher intake of fiber were significantly associated with lower levels of depressive symptoms. Both subjective and objective physical health significantly mediated the relationship between variables of diet and mild depressive symptoms. Subjective physical health also significantly mediated the relationship between high intake of dietary fiber and lower likelihood of reporting severe depressive symptoms. ConclusionDespite being cross-sectional in nature, this study presented evidence that gut-health promoting diets may reduce depressive symptoms through improving physical health. These findings provide preliminary support to diet programs for preventing depression and diet programs as an alternative or supplementary treatment of depression.

Dietary Fiber Intake and Gut Microbiota in Human Health.

Dietary fiber is fermented by the human gut microbiota, producing beneficial microbial metabolites, such as short-chain fatty acids. Over the last few centuries, dietary fiber intake has decreased tremendously, leading to detrimental alternations in the gut microbiota. Such changes in dietary fiber consumption have contributed to the global epidemic of obesity, type 2 diabetes, and other metabolic disorders. The responses of the gut microbiota to the dietary changes are specific to the type, amount, and duration of dietary fiber intake. The intricate interplay between dietary fiber and the gut microbiota may provide clues for optimal intervention strategies for patients with type 2 diabetes and other noncommunicable diseases. In this review, we summarize current evidence regarding dietary fiber intake, gut microbiota modulation, and modification in human health, highlighting the type-specific cutoff thresholds of dietary fiber for gut microbiota and metabolic outcomes.

Diet and Risk of Non-Alcoholic Fatty Liver Disease, Cirrhosis, and Liver Cancer: A Large Prospective Cohort Study in UK Biobank.

Background and Aims: Epidemiological evidence has shown the association between nutritional habits and liver disease. However, results remain conflicting. This study investigated the influence of dietary factors on the risk of incident non-alcoholic fatty liver disease (NAFLD), cirrhosis, and liver cancer. Methods: Data from the UK Biobank database were analyzed (n = 372,492). According to baseline data from the food frequency questionnaire, two main dietary patterns (Western and prudent) were identified using principal component analysis. We used cox proportional hazards models to explore the associations of individual food groups and dietary patterns with NAFLD, cirrhosis, and liver cancer. Results: During a median follow-up of 12 years, 3527 hospitalized NAFLD, 1643 cirrhosis, and 669 liver cancer cases were recorded among 372,492 participants without prior history of cancer or chronic liver diseases at baseline. In multivariable adjusted analysis, participants in the high tertile of Western dietary pattern score had an 18% (95%CI = 1.09−1.29), 21% (95%CI = 1.07−1.37), and 24% (95%CI = 1.02−1.50) higher risk of incident NAFLD, liver cirrhosis, and liver cancer, respectively, compared with the low tertile. Participants in the high tertile of prudent scores had a 15% (95%CI = 0.75−0.96) lower risk of cirrhosis, as compared with those in the low tertile. In addition, the higher consumption of red meat and the lower consumption of fruit, cereal, tea, and dietary fiber were significantly associated with a higher risk of NAFLD, cirrhosis, and liver cancer (ptrend < 0.05). Conclusions: This large prospective cohort study showed that an increased intake of food from the Western dietary pattern could be correlated with an increased risk of chronic liver diseases, while the prudent pattern was only correlated with a reduced liver cirrhosis risk. These data may provide new insights into lifestyle interventions for the prevention of chronical liver diseases.

The microbiome’s fiber degradation profile and its relationship with the host diet

BackgroundThe relationship between the gut microbiome and diet has been the focus of numerous recent studies. Such studies aim to characterize the impact of diet on the composition of the microbiome, as well as the microbiome’s ability to utilize various compounds in the diet and produce metabolites that may be beneficial for the host. Consumption of dietary fibers (DFs)—polysaccharides that cannot be broken down by the host’s endogenous enzymes and are degraded primarily by members of the microbiome—is known to have a profound effect on the microbiome. Yet, a comprehensive characterization of microbiome compositional and functional shifts in response to the consumption of specific DFs is still lacking.ResultsHere, we introduce a computational framework, coupling metagenomic sequencing with careful annotation of polysaccharide degrading enzymes and DF structures, for inferring the metabolic ability of a given microbiome sample to utilize a broad catalog of DFs. We demonstrate that the inferred fiber degradation profile (IFDP) generated by our framework accurately reflects the dietary habits of various hosts across four independent datasets. We further demonstrate that IFDPs are more tightly linked to the host diet than commonly used taxonomic and functional microbiome-based profiles. Finally, applying our framework to a set of ~700 metagenomes that represents large human population cohorts from 9 different countries, we highlight intriguing global patterns linking DF consumption habits with microbiome capacities.ConclusionsCombined, our findings serve as a proof-of-concept for the use of DF-specific analysis for providing important complementary information for better understanding the relationship between dietary habits and the gut microbiome.

Dietary Intake and Physical Activity of Thai Children and Adolescents with Type 1 Diabetes Mellitus.

Appropriate dietary intake and physical activity (PA) are essential for glycemic control and optimal growth in youth with type 1 diabetes (T1D). Thus, this study aimed to compare dietary intake and PA between youth with T1D and healthy controls. One hundred Thai youth with T1D and 100 age-matched healthy participants were recruited. A 3-day food record was completed and converted into nutrient intake data. PA data were collected via interview. Participants with T1D had a significantly higher mean ± SD carbohydrate (50.8 ± 6.8% vs. 46.2 ± 7.5%, p < 0.01), lower fat (32.4 ± 5.9% vs. 35.9 ± 6.4%, p < 0.01), and lower protein (16.8 ± 2.6% vs. 17.9 ± 3.5%, p = 0.01) intake compared to controls. Fifty percent of T1D participants and 41% of control participants consumed saturated fat more than recommendations (p = 0.20). Participants with T1D had a higher median (IQR) calcium intake compared to controls (474 (297−700) vs. 328 (167−447) mg/day, p < 0.01). Both groups consumed less fiber and more sodium compared to recommendations. Both groups had inadequate PA. Participants with T1D had significantly less PA compared to controls (25 (13−48) vs. 34 (14−77) minutes/day, p = 0.04). In addition to the need for counseling that promotes consumption of more dietary fiber and calcium and less saturated fat and sodium, the benefits of performing regular exercise need to be emphasized among youth with T1D.

The Implications of Connexin 43 Deficiency during the Early Stages of Chemically Induced Mouse Colon Carcinogenesis.

Colorectal cancer (CRC), associated with an increased intake of processed red meats, saturated fats, and simple carbohydrates accompanied by low dietary fiber, fruits, and vegetables consumption, presents a high epidemiological burden. Connexin43 (Cx43) protein, which forms gap junctions or hemichannels, has tumor suppressor or oncogenic activities in a cancer type- and stage-dependent manner. Cx43 expression varies during colon carcinogenesis, and its functional role is not fully understood. Thus, we evaluated the implications of Cx43 heterologous deletion (Cx43+/-) during the early stages of a chemically induced model of colon carcinogenesis. Female C57BL/6J mice (wild-type or Cx43+/-) were submitted to a colon carcinogenesis model induced by 1,2 dimethylhydrazine (DMH). Mice were euthanized eight hours (week 7) or 30 weeks (week 37) after the last DMH administration to evaluate subacute colon toxicity outcomes or the burden of (pre)neoplastic lesions, respectively. At week 7, Cx43 deficiency inferred no alterations in the DMH-induced increase in systemic (peripheral blood), in situ (colonocytes) DNA damage, and apoptosis in the colonocytes. At week 30, Cx43+/- mice presented an increase in preneoplastic aberrant crypt foci (ACF) multiplicity, while no alterations were observed in colorectal adenoma (CRA) occurrence, multiplicity, volume, proliferation, growth, and β-catenin immunoexpression. Similarly, an in silico analysis of human CRA showed decreased mRNA expression of Cx43 with no correlation with proliferation, apoptosis, and β-catenin markers. These findings indicate the discrete role of Cx43 in the early stages of chemically induced mouse colon carcinogenesis.