Insoluble Fiber Intake Research Articles

Dietary soluble, insoluble, and total fiber intake and their dietary sources in association with breast cancer

BackgroundA few studies have examined the association between different types of dietary fiber as well as their sources and the risk of breast cancer (BC) and the present study aimed to investigate these associations in a case-control study among Iranian women.MethodsA total of 464 women with pathologically confirmed breast cancer within the past year and 498 age-matched healthy controls were included. Dietary intakes were assessed using a 168-item food frequency questionnaire. The association between dietary soluble, insoluble, total dietary fiber, as well as, fiber from fruits, vegetables, legumes, cereals, and nuts intake with odds of breast cancer was assessed using multivariate logistic regression analysis.ResultsMean total dietary fiber intake of patients with and without cancer were 33.1 ± 15.3 g per day (g/d) and 34.2 ± 16.5 (g/d), respectively. Dietary total fiber (OR = 0.65; 95%CI: 0.47–0.90, Ptrend = 0.01), insoluble fiber (OR = 0.68; 95%CI: 0.49–0.93, Ptrend = 0.01), fruits’ fiber (OR = 0.68; 95%CI: 0.49–0.94, Ptrend = 0.02), and vegetables’ fiber (OR = 0.66; 95%CI: 0.48–0.91, Ptrend = 0.01) were significantly associated with reduced likelihood of developing breast cancer in all participants. Furthermore, dietary total and insoluble fiber, as well as, fiber from fruits were significantly associated with lower odds of breast cancer in premenopausal women (P < 0.05). In contrast, cereals’ fiber significantly increased the risk of breast cancer by 84% in premenopausal women (OR = 1.84; 95%CI: 1.18–2.86, Ptrend = 0.009). In postmenopausal women, cereals’ fiber had a significant inverse association with odds of breast cancer (OR = 0.56; 95%CI: 0.31–1.03, Ptrend = 0.04). Also, fiber from vegetables was significantly associated with a lower risk of breast cancer in postmenopausal women (OR = 0.53; 95%CI: 0.30–0.94, Ptrend = 0.03).ConclusionDietary fiber intake and more specifically insoluble, fruits’, and vegetables’ fiber intake might be associated with a reduced breast cancer risk, particularly in premenopausal women. Future prospective investigations are needed to confirm these findings.

Relationship between Sources of Dietary Fiber Intake and Homocysteine Metabolism in Relation to Serum Homocysteine Concentrations

While homocysteine is produced as an intermediate metabolite during methionine metabolism, increased blood homocysteine levels are associated with various diseases. In a previous cross-sectional study, we reported a significant negative association between the serum concentrations of homocysteine in 227 young women and their dietary fiber intake. In the present study, we examined the relationship between dietary fiber intake from food sources and serum levels of homocysteine and its metabolites. Homocysteine and its metabolites 5-methyltetrahydrofolate (5MTHF), cystathionine, glycine, methionine, and S-adenosyl-methionine were measured using LC-MS/MS. The soluble, insoluble, and total fiber intake from fruits and mushrooms was significantly inversely correlated with the homocysteine concentrations. Furthermore, the soluble, insoluble, and total fiber intake from fruits was significantly positively associated with the serum 5MTHF concentrations, while the fiber intake from mushrooms was positively correlated with the cystathionine concentration and negatively correlated with the methionine and glycine concentrations. These results suggest that ingesting dietary fiber in the form of fruits and mushrooms maintains a low concentration of homocysteine by activating two different homocysteine-scavenging metabolic pathways.

Sex difference in the association of dietary fiber intake with visceral fat volume in Japanese adults.

Dietary fiber is a possible nutritional component which aids in the prevention of visceral fat accumulation. We examined the association between dietary fiber intake and visceral fat volume (VFV) by sex, and further analysed the association by major food sources of dietary fiber. In this cross-sectional study, we measured VFV in 2779 Japanese (1564 men and 1215 women) aged 40-89 who underwent positron emission tomography/computed tomography for cancer screening between 2004 and 2005. Dietary fiber intake was calculated based on a validated semi-quantitative food frequency questionnaire. The association between dietary fiber intake and VFV was investigated using multivariate linear regression models after adjustment for potential confounders. Total, soluble, and insoluble fiber intakes were inversely associated with VFV in men (Q1: 3740 cm3, Q4: 3517 cm3, Ptrend: 0.0006 for total fiber), but not in women (Q1: 2207 cm3, Q4: 2193 cm3,Ptrend: 0.88 for total fiber). Statistically significant sex difference was observed (Pinteraction = 0.001 for total fiber). Subgroup analyses by major food sources revealed that dietary fiber intakes from beans, vegetables and fruits showed an inverse association with VFV in men, while cereal fiber intake showed a tendency toward a positive association in both sexes (Q1: 3520 cm3, Q4: 3671 cm3, Ptrend: 0.05 in men, Q1: 2147 cm3, Q4: 2227 cm3, Ptrend: 0.10 in women). We observed a sex-specific association between dietary fiber intake and VFV in Japanese adults. This study suggests that efforts against visceral fat accumulation should take account of the source of dietary fiber.

Higher insoluble fiber intake is associated with a lower risk of prostate cancer: results from the PLCO cohort

Studies regarding the relationship between fiber intake and prostate cancer (PCa) have conflicting results. Therefore, this study examined the relationship between fiber intake and the risk of PCa by using data from Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial. A total of 54,336 participants in the United States, consisting of 6,414 patients with PCa, were included in this study. Multivariate Cox regression models were applied to estimate adjusted hazard ratios (aHRs) and corresponding 95% confidence intervals (CIs). Compared with individuals in the lowest quartile, individuals in the highest quartile of insoluble fiber intake had a significantly lower risk of PCa (aHR, 0.87; 95% CI, 0.78–0.98). By contrast, no significant associations were detected between total fiber intake (aHR, 0.90; 95% CI, 0.80–1.01) or soluble fiber intake (aHR, 0.90; 95% CI, 0.80–1.02). Subgroup analyses showed that insoluble fiber was related to a decreased risk of PCa in subjects with the following characteristics: age > 65 years, nonsmoking or former smokers, education level ≤ high school, non-Hispanic white ethnicity, or without a family history of PCa. In addition, significant combined effects of insoluble fiber intake, age and family history of PCa on the risk of PCa were observed, but no combined effects of smoking status and insoluble fiber intake were observed. In addition, total fiber, insoluble fiber, and soluble fiber intake had no influence on the mortality of PCa patients. These results show that all 3 measures of fiber suggest a protective association, but insoluble fiber may have a stronger association with the risk of PCa. Future studies are warranted to further investigate these relationships.

Current Status of Research on Diets High in Dietary Fiber for Patients with Gestational Diabetes Mellitus

The purpose of this study is to analyze whether the intake of soluble dietary fiber plays a positive role in regulating the blood glucose level of patients with gestational diabetes mellitus through the comparative analysis of experimental data of the previous researchers and the dietary nutritional data of various countries, and to explore whether supplementing the nutritional combination of high soluble dietary fiber has a positive effect on blood glucose level of patients with diabetes mellitus in the whole period of pregnancy and thus verify whether high soluble dietary fiber has an effective intervention effect or even a therapeutic effect on controlling the blood glucose level of patients with gestational diabetes mellitus. The effect of supplementation with highly soluble dietary fiber on the blood glucose level of patients with gestational diabetes mellitus in the whole pregnancy period, so as to verify whether highly soluble dietary fiber has an effective intervention effect or even a therapeutic effect on the control of blood glucose level of gestational diabetes mellitus patients. Compare and contrast with the intake of insoluble dietary fiber, and compare and discuss whether different dietary fibers have different effects on the blood glucose level of gestational diabetes mellitus patients. It also summarizes the current methods of dietary fiber intervention in the treatment of gestational diabetes mellitus, and thus provides an outlook on the possible tendencies of future development.

Postprandial hyperglycemia in patients with type 2 diabetes is reduced by raw insoluble fiber: A randomized trial

Background and aimsA lower risk of type 2 diabetes mellitus (T2DM) is associated with the intake of insoluble fiber. This contradicts the postulate that insoluble fibers do not decrease postprandial glycemic response and that only viscous gel-forming soluble fibers would do this. This study aimed to investigate the effect of a dose of insoluble fibers that meets dietary recommendations on postprandial hyperglycemia in T2DM patients. Methods and resultsThis is a randomized crossover clinical trial. Nineteen T2DM men randomly ate a balanced breakfast either without (Control) or with prior consumption of insoluble fibers (5.8 g) in the form of 15 g of raw wheat bran (RWB). Glycemia was measured at fasting and 15, 30, 45, 60, 90, and 120 min postprandially. Markers of taste intensity and palatability were assessed after breakfast intake. The glucose peak rise of 87 mg/dL and the incremental area under the curve (AUC) elicited by the breakfast were decreased by RWB (15.80 % and 23.14 %, respectively). Time-to-glucose-peak did not differ between groups. The addition of the RWB to the meal decreased its level of creaminess and tasty and increased the sourness and bitterness. ConclusionsThe postprandial hyperglycemia in T2DM patients in response to complex carbohydrates was decreased by prior intake of a recommended dose of raw insoluble fibers. This antihyperglycemic effect is in accordance with the acarbose-like property of raw insoluble fibres, but not of heated ones (e.g., bread and pasta), to inhibit the activities of the carbohydrate-digesting enzymes alpha-glucosidase/alpha-amylase. Registration number for clinical trialsRBR-98tx28b (https://ensaiosclinicos.gov.br/rg/RBR-98tx28b).

Relationship between Serum Homocysteine Concentration and Dietary Factors in Young Japanese Women.

Homocysteine is a methionine metabolism intermediate and its increased blood levels are associated with a higher risk of noncommunicable diseases. Reportedly, blood homocysteine levels increase with inadequate folate, vitamin B6, and vitamin B12 intake; however, its relationship with dietary factors other than these three vitamins remains unknown. Thus, we investigated the relationship of homocysteine with other nutrient intake. We performed a dietary survey on 227 young women using a food record with approximate amounts for 7 consecutive days in conjunction with digital imaging. We collected early morning fasting blood samples the day after the dietary survey was completed and analyzed the serum homocysteine levels. We observed that the serum homocysteine concentrations were significantly negatively associated with soluble, insoluble, and total fiber intake. In addition, participants with high fruit and mushroom intake displayed lower serum homocysteine concentrations, suggesting dietary fiber involvement from these foods. However, we observed no serum homocysteine concentration-related association with cereals and vegetables (well-documented dietary fiber sources) or with fruits and mushrooms. In conclusion, fiber quality-related differences could thus be caused by different sources, including antioxidant components such as fruit polyphenols and mushroom antioxidant and anti-inflammatory factors.

Detoxified castor seed meal replaces soybean meal in the supplement for Holstein-Zebu crossbred steers finished on tropical pasture during the rainy season.

The objective of this study was to examine the effect of replacing soybean meal (SBM) with detoxified castor seed meal (DCM) on the intake, digestibility, feeding behavior, and performance of pasture-finished (rainy season) steers supplemented with concentrate at 0.4% of their body weight. Forty ½ Holstein + ½ Zebu steers (initial weight: 283.3 ± 36.3kg) were allocated to four treatments in a completely randomized experimental design. Treatments consisted of diets in which DCM replaced 0, 30, 60, and 90% of SBM in the supplement dry matter (DM). The steers were finished on an Urochloa brizantha pasture and the experiment lasted 112days. Replacing SBM with DCM did not influence (P > 0.05) the intake or apparent digestibility of DM, crude protein, or neutral detergent insoluble fiber of the animals. Grazing time increased (P < 005), whereas the intake and rumination efficiencies of the steers did not change (P > 0.05) with the substitution. The replacement of SBM with DCM in the supplement fed to the steers also did not influence (P > 0.05) their final weight, average daily gain, or feed conversion (P > 0.05). We recommend replacing up to 90% (DM basis) of SBM with DCM in the concentrate supplement of steers grazing on Urochloa brizantha pasture during rainy season while supplemented with concentrate at 0.4% of their body weight.

Associations between Dietary Sugar and Fiber with Infant Gut Microbiome Colonization at 6 Mo of Age

BackgroundThe taxonomic composition of the gut microbiome undergoes rapid development during the first 2–3 y of life. Poor diet during complementary feeding has been associated with alterations in infant growth and compromised bone, immune system, and neurodevelopment, but how it may affect gut microbial composition is unknown. ObjectivesThis cross-sectional study aimed to examine the associations between early-life nutrition and the developing infant gut microbiota at 6 mo of age. MethodsLatino mother–infant pairs from the Mother’s Milk Study (n = 105) were included. Infant gut microbiota and dietary intake were analyzed at 6 mo of age using 16S ribosomal RNA amplicon sequencing and 24-h dietary recalls, respectively. Poisson generalized linear regression analysis was performed to examine associations between dietary nutrients and microbial community abundance while adjusting for infants’ mode of delivery, antibiotics, infant feeding type, time of introduction of solid foods, energy intake, and body weight. A P value of <0.05 was used to determine the statistical significance in the study. ResultsInfants with higher consumption of total sugar exhibited a lower relative abundance of the genera Bacteroides (β = −0.01; 95% CI: −0.02, −0.00; P = 0.03) and genus Clostridium belonging to the Lachnospiraceae family (β = −0.02; 95% CI: −0.03, −0.00; P = 0.01). In addition, a higher intake of free sugar (which excludes sugar from milk, dairy, and whole fruit) was associated with several bacteria at the genus level, including Parabacteroides genus (β = 0.03; 95% CI: 0.01, 0.05; P = 0.001). Total insoluble fiber intake was associated with favorable bacteria at the genus level such as Faecalibacterium (β = 0.28; 95% CI: 0.03, 0.52; P = 0.02) and Coprococcus (β = 0.28; 95% CI: 0.02, 0.52; P = 0.03). ConclusionThese findings demonstrate that early-life dietary intake at 6 mo impacts the developing gut microbiome associated with the presence of both unfavorable gut microbes and dietary fiber-associated commensal microbes.

Types of fiber and gut microbiota composition and diversity among arab females

ObjectivesDietary fiber is recognizedas an important nutrient for gut health. However, research on the relations of different types of fibers (soluble and insoluble) to the human microbiota health is limited. This study aimed to identify whether higher habitual intake of soluble and/or insoluble fiber have a different influence on the composition, diversity, and abundance of microbiota. MethodsWe examined the fecal microbial composition of 92 healthy females aged 18 and above using the novel shotgun metagenomics sequencing technique. The habitual fiber intake was determined using the Saudi food frequency questionnaire. Pearson’s correlation was used for the correlations between total, soluble, and insoluble fiber and gut microbiota. α- and β-diversities were applied to acquire the distinctions in the relative abundances of bacterial taxa. ResultsOur findings show that higher dietary fiber, particularly insoluble fiber, was significantly correlated with the abundances of Bacteroides_u_s, Bacteroides uniformis, and Lactobacillus acidophilus (r = 0.26, 0.29, 0.26, p-value < 0.05, respectively). Non-significant difference was noted in the microbial α-diversity and β-diversity in low and high soluble/insoluble dietary fiber. ConclusionsCurrent findings suggest that insoluble dietary-fiber intake is favorably correlated with the health of the human gut microbiota. However, further investigations are necessary to identify the effect of types of fiber on the specific species identified in this study.

THE EFFECT OF LOW-FIBER DIETS ON COLORECTAL CANCER INCIDENCE IN SOUTHEAST AND EAST ASIA: SYSTEMATIC REVIEW AND META-ANALYSIS

Introduction : Colorectal cancer is a malignant tumor that grows in the colon tissue. In the Asian region, in 2018, cases and deaths from colorectal cancer are highest in East Asia (there were 736,573 cases and 325,128 of them died) and Southeast Asia (there were 95,223 cases and 52,475 of them died). Aims: Several studies have been conducted regarding the effect of a low-fiber diet and an increased risk of colorectal cancer, but it still shows mixed results. Methods: This study is an unobstrutive study with a systematic review and meta-analysis method. Data sources came from 14 primary studies with a case-control study design that met the inclusion criteria. Data analysis was performed using CMA software trial version 3.0 with a confidence level of α = 5%. Research with low-fiber diet variables shows heterogeneous variations in results so that the chosen model is random effect model. Result: The analysis states that there was a significant relationship between a low-fiber diet (CI: 0.421–0.867) and an increased risk of colorectal cancer due to the role of soluble and insoluble fiber. Lack of intake of soluble fiber can decrease insulin action and blood sugar control or the production of short-chain fatty acids, whereas insufficient intake of insoluble fiber can increase the potential for interactions between mutagens and colonic mucosa. Conclusion: The results of the study are expected to be an input for a proper diet so that there is no increase in cases of colorectal cancer.

Dietary fiber intake and mortality among survivors of liver cirrhosis: A prospective cohort study

BackgroundLiver cirrhosis is associated with significant nutritional risks and poor survival rates. Little is known about the impact of dietary factors on metabolic complications and mortality from cirrhosis. AimThe present study investigated the potential associations between dietary fibers and the risk of cirrhosis-related mortality. MethodsIn this prospective study, 121 ambulatory cirrhotic patients with more than six months of cirrhosis diagnosis were followed-up for 4 years. Dietary intakes were assessed using a 168-item semi-quantitative validated food frequency questionnaire. Crude and multivariable-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated through cox proportional hazards regression models. ResultsComparing the highest versus the lowest tertile, soluble and insoluble fiber intake was associated with 62% (HR = 0.38, 95% CI = 0.045–3.5, p trend = 0.047) and 73% (HR = 0.27, 95% CI = 0.06–1.2, p trend = 0.021) lower mortality risk, respectively, after full adjustment for potential confounders. Higher intakes of total fiber were inversely but non-significantly associated with mortality risk. ConclusionComprehensive assessment of dietary fiber intake associations with cirrhosis-related mortality showed that higher intakes of soluble and insoluble fiber were significantly associated with reduced mortality risk.

Maternal Bean Consumption during Pregnancy: Distribution and Nutritional Outcomes

(1) Background: Due to their high nutritional value, we aimed to characterize the frequency and amount of maternal consumption of beans during pregnancy and their associations with diet quality and nutrient intake. (2) Methods: We conducted a secondary data analysis of US pregnant women (n = 1444) from the Infant Feeding Practices Study II, a longitudinal study that followed mother–infant pairs from late pregnancy to 1 year postpartum. Maternal bean intake (food types [dried beans, chili, and bean soup], frequency, serving size, and amount), diet quality (Healthy Eating Index [HEI]), and nutrient intake were estimated with a Food Frequency Questionnaire taken in the third trimester of pregnancy. Associations of bean consumption with diet quality and nutrient intake were examined with analysis of variance, Fisher’s least significant difference tests, correlation coefficients, and coefficients of determination. (3) Results: In general, maternal bean consumption was low during pregnancy: 0.31 cups/week of dried beans, 0.37 cups/week of chili, and 0.10 cups/week of bean soup. Maternal bean consumption varied by socio-demographics and geographic regions. In comparison with those who never consumed dried beans, mothers who ate dried beans ≥ 1 time per week had a higher mean HEI score (67.5 vs. 63.6), intake of total fiber (24.4 vs. 17.4 g/day), and protein (93.4 vs. 79.9 g/day), but a lower percentage of energy from added sugar (12.6 vs. 15.2%). Higher dried bean consumption had weak-to-moderate correlations with intake of total fiber (correlation coefficient, 0.320), insoluble fiber (0.316), soluble fiber (0.310), and folate (0.286). Similar but less extensive correlations were observed for chili and bean soup consumption. (4) Conclusions: In this US cohort of pregnant women, bean consumption was low. Increased intake of beans (≥1 time per week) may improve maternal diet quality during pregnancy.

Impact of Diet on Nutrient Intake, Glycemic Index and Glycemic Load of Meals of Urban Indian Diabetic Population

Background: India is heading toward becoming the global diabetic capital directly interconnected to poor lifestyle and obesity. Aims and Objectives: The aim of the study was to find an association between glycemic index (GI) and glycemic load (GL) with macronutrients and fiber in the diet of the urban Indian population. Materials and Methods: The dietary intake using food frequency questionnaire and 24–h dietary recall of 240 recruited subjects (male and female), between 25 and 60 years were taken in the study. GI and GL of all meals were calculated using values from National and the International Table of GI and GL. Results: Average mean and standard deviation of GI and GL of major meals were on the higher side. A significant correlation between GI of lunch and dinner with total available carbohydrate (CHO) and total starch intake. A positive significant correlation was observed between GI to energy intake at dinner, total available CHO, and total starch. GL of breakfast was negatively correlated to iron, zinc, insoluble, and soluble fiber intake in females. GL for lunch was positively correlated to the intake of total available CHO, total starch, insoluble, and soluble fiber. Conclusion: The present study showed high GI and GL of processed foods and refined CHO indicating that dietary habits with high GI and GL foods are an indicator to risk of diabetes and pre-diabetes among both genders.

Defecation status, intestinal microbiota, and habitual diet are associated with the fecal bile acid composition: a cross-sectional study in community-dwelling young participants

PurposeBile acid (BA) metabolism by intestinal bacteria is associated with the risk of gastrointestinal diseases; additionally, its control has become a modern strategy for treating metabolic diseases. This cross-sectional study investigated the influence of defecation status, intestinal microbiota, and habitual diet on fecal BA composition in 67 community-dwelling young participants.MethodsFeces were collected for intestinal microbiota and BA analyses; data about defecation status and dietary habits were collected using the Bristol stool form scales and a brief-type self-administered diet history questionnaire, respectively. The participants were categorized into four clusters based on their fecal BA composition, according to cluster analysis, and tertiles based on deoxycholic acid (DCA) and lithocholic acid (LCA) levels.ResultsThe high primary BA (priBA) cluster with high fecal cholic acid (CA) and chenodeoxycholic acid (CDCA) levels had the highest frequency of normal feces, whereas the second BA (secBA) cluster with high levels of fecal DCA and LCA had the lowest. Alternately, the high-priBA cluster had a distinct intestinal microbiota, with higher Clostridium subcluster XIVa and lower Clostridium cluster IV and Bacteroides. The low-secBA cluster with low fecal DCA and LCA levels had the lowest animal fat intake. Nevertheless, the insoluble fiber intake of the high-priBA cluster was significantly higher than that of the high-secBA cluster.ConclusionHigh fecal CA and CDCA levels were associated with distinct intestinal microbiota. Conversely, high levels of cytotoxic DCA and LCA were associated with increased animal fat intake and decreased frequency of normal feces and insoluble fiber intake.Clinical trial registryUniversity Hospital Medical Information Network (UMIN) Center system (UMIN000045639); date of registration: 15/11/2019.

Variety and quantity of dietary insoluble fiber intake from different sources and risk of new-onset hypertension

BackgroundThe relations of the variety and quantity of different sources of dietary insoluble fibers and hypertension remain uncertain. We aimed to investigate the associations between the variety and quantity of insoluble fibers intake from six major food sources and new-onset hypertension, using data from the China Health and Nutrition Survey (CHNS).MethodsTwelve thousand one hundred thirty-one participants without hypertension at baseline from CHNS were included. Dietary intake was measured by three consecutive 24-h dietary recalls combined with a household food inventory. The variety score of insoluble fiber sources was defined as the number of insoluble fiber sources consumed at the appropriate level, accounting for both types and quantities of insoluble fibers. The study outcome was new-onset hypertension, defined as blood pressure ≥ 140/90 mmHg, or physician-diagnosed hypertension or receiving antihypertensive treatments during the follow-up.ResultsDuring a median follow-up of 6.1 years, 4252 participants developed hypertension. There were L-shaped associations of dietary insoluble fibers derived from vegetables, beans, tubers, and fruits with new-onset hypertension; a reversed J-shaped association of whole grain-derived insoluble fiber with new-onset hypertension; and no obvious association of refined grain-derived insoluble fiber with new-onset hypertension. Therefore, refined grain was not included in the insoluble fiber variety score calculation. More importantly, a higher insoluble fiber variety score was significantly associated with lower risks of new-onset hypertension (per score increment, hazard ratio, 0.50; 95% CI, 0.45–0.55).ConclusionsThere was an inverse association between the variety of insoluble fibers with appropriate quantity from different food sources and new-onset hypertension.

Total and different dietary fiber subtypes and the risk of all-cause, cardiovascular, and cancer mortality: a dose-response meta-analysis of prospective cohort studies.

We aimed to conduct a comprehensive review of the association between dietary fiber and the risk of mortality. We did a systematic search in PubMed, Scopus, and Web of Science up to November 2022 to find prospective cohort studies of the relationship between total and subtypes of dietary fiber and the risk of all-cause, cardiovascular (CVD), and cancer mortality in the general population. The hazard ratios (HRs) and 95% CIs were calculated using a random-effects model. A total of 28 studies with 1 613 885 participants were included. Higher intake of total and subtypes of dietary fiber including cereal, vegetable, legume, soluble, and insoluble fiber, but not fruit fiber, was associated with a lower risk of all-cause mortality, with HRs ranging from 0.77 for insoluble fiber to 0.93 for legume fiber. Similar findings were observed for CVD mortality, where higher intake of total and all subtypes of dietary fiber was each associated with a lower risk. Higher intake of total, cereal, vegetable, and insoluble fiber was also associated with a lower risk of cancer mortality. No association was found between the intake of fruit, legume, and soluble fiber and cancer mortality. Dose-response meta-analyses suggested an inverse association between total fiber intake and the risk of all-cause, CVD, and cancer mortality. The certainty of evidence was rated moderate for the association of total fiber with all-cause, CVD, and cancer mortality. In conclusion, our findings highlight the potential advantages of consuming a wide range of dietary fiber subtypes against all-cause, CVD, and cancer mortality. Registry and registry number: PROSPERO (CRD42021226816).

Variety and Quantity of Dietary-Insoluble Fiber Intake From Different Sources and Risk of New-Onset Diabetes.

The relationship between the variety and quantity of different sources of dietary-insoluble fiber intake and diabetes remain uncertain. We aimed to investigate the associations between the variety and quantity of insoluble fiber intake from 6 major food sources and new-onset diabetes, using data from the China Health and Nutrition Survey (CHNS). A total of 16 272 participants without diabetes at baseline from CHNS were included. Dietary intake was measured by 3 consecutive 24-hour dietary recalls combined with a household food inventory. Energy-adjusted dietary intake was used in analyses. The variety score of insoluble-fiber sources was defined as the number of specific-sourced insoluble fiber consumed at the appropriate level, accounting for both types and quantity of insoluble fiber. Participants with self-reported physician-diagnosed diabetes, or fasting glucose greater than or equal to 7.0 mmol/L or glycated hemoglobin A1c greater than or equal to 6.5% during follow-up were defined as having new-onset diabetes. During a median follow-up of 9.0 years, 1101 participants developed new-onset diabetes. There were U-shaped associations for energy-adjusted dietary intake of total insoluble fiber, and energy-adjusted insoluble fiber derived from refined and whole grains; and L-shaped associations for energy-adjusted insoluble fiber derived from vegetables, legumes, fruits, and tubers with new-onset diabetes (all P for nonlinearity < .001). Moreover, a higher variety score of insoluble fiber sources was significantly associated with a lower risk of new-onset diabetes (per 1-score increment, hazard ratio, 0.61; 95% CI, 0.58-0.65). There was an inverse association between the variety of insoluble fiber with appropriate quantity from different food sources and new-onset diabetes.

Associations between dietary fiber intake and mortality from all causes, cardiovascular disease and cancer: a prospective study

ObjectiveSeveral studies suggest that dietary fiber intake may reduce mortality risk, but this might depend on the fiber types and the evidence regarding the role of soluble fiber or insoluble fiber on death risk remain limited and inconsistent. Therefore, this study aimed to comprehensively evaluate multiple types of dietary fiber intake on mortality from all causes, cardiovascular disease and cancer in the large-scale Prostate, Lung, Colorectal, and Ovarian Cancer (PLCO) Screening Trial.MethodsA multivariate Cox proportional hazards model was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs).ResultsThis study finally included 86,642 participants with 17,536 all-cause deaths, 4842 cardiovascular deaths and 5760 cancer deaths identified after a total of 1,444,068 follow-up years. After adjusting for potential confounders, dietary total fiber intake was statistically significantly inversely associated with all-cause death (Q5 vs Q1: HR 0.71, 95% CI 0.66–0.75; P for trend < 0.001), cardiovascular death (Q5 vs Q1: HR 0.73, 95% CI 0.65–0.83; P for trend < 0.001) and cancer mortality (Q5 vs Q1: HR 0.77, 95% CI 0.69–0.86; P for trend < 0.001). Similar results were observed for both insoluble and soluble fiber intake. Restricted cubic spline model analysis suggested that there was a nonlinear association of dietary fiber intake with mortality risk (all P for nonlinearity < 0.05).ConclusionsIn this large nationally representative sample of US adult population, intakes of total fiber, soluble fiber, and insoluble fiber were associated with lower risks of all-cause, cardiovascular and cancer mortality.

Maternal Dry Bean Consumption During Pregnancy: Distribution and Nutritional Outcomes

ObjectivesDry beans and other pulses have a high nutritional profile. We aimed to characterize the frequency and amount of maternal dry bean consumption during pregnancy and their associations with diet quality and nutrient intake.MethodsWe conducted a secondary data analysis of pregnant women (N = 1,403) from the Infant Feeding Practices Study II, a longitudinal study that followed mother-infant pairs from late pregnancy until 6 years postpartum. Maternal dry bean consumption (frequency and amount), diet quality (Healthy Eating Index [HEI]), and nutrient intake were estimated with a Food Frequency Questionnaire completed in the third trimester of pregnancy. Associations of dry bean consumption with dietary quality and nutrient intake were examined with Analysis of Variance, Tukey's HSD pairwise comparisons, and determination coefficients.ResultsMothers in the analytic sample were mainly White (83.5%), college educated (78.9%), and had middle household income (55.1% ≥ $40,000). Overall, maternal dry bean consumption was low (0.3 cups/week) during pregnancy, with 92% not meeting the current recommendation (1–3 cups/week). Maternal dry bean consumption significantly varied by race/ethnicity and geographic regions with mothers of Hispanics and Asian or living in South Central regions having relatively high consumption. Compared with never-consumers, mothers who consumed dry beans ≥ 1 time per week had a higher mean HEI score (67.5 vs 63.6), intake of total fiber (24.4 vs 17.4 g/d), and protein (93.4 vs 79.9 g/d), but a lower percentage of energy (12.6 vs 15.2%) from added sugar. Higher amount of dry bean consumption had a substantial contribution to the variation in intake of total fiber (determination coefficient, 10.3%), insoluble fiber (10.0%), soluble fiber (9.6%), and folate (8.2%).ConclusionsDry bean consumption was low during pregnancy. Consumption of dry beans ≥ 1 time per week might help to improve maternal diet quality.Funding SourcesUSDA (to XW and TR).