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BACKGROUND: In healthy adults, higher dietary potassium intake is recommended given that potassium-rich foods are major sources of micronutrients, antioxidants, and fiber. Yet among patients with advanced kidney dysfunction, guidelines recommend dietary potassium restriction given concerns about hyperkalemia leading to malignant arrhythmias and mortality. OBJECTIVES: Given sparse data informing these recommendations, we examined associations of dietary potassium intake with mortality in a nationally representative cohort of adults from the NHANES. METHODS: We examined associations between daily dietary potassium intake scaled to energy intake (mg/1000 kcal), ascertained by 24-h dietary recall, and all-cause mortality among 37,893 continuous NHANES (1999-2014) participants stratified according to impaired and normal kidney function (estimated glomerular filtration rates

BackgroundTraditional diets are often credited for the robust cardiometabolic health of subsistence populations. Yet, rural subsistence populations are undergoing nutrition transitions that have been linked to the increase in chronic noncommunicable diseases. Few studies have presented detailed dietary estimates in transitioning populations.ObjectivesWe aimed to 1) characterize and compare dietary profiles of 2 neighboring subsistence populations in Bolivia who vary in market integration and 2) identify dietary factors contributing to low cardiovascular disease risk.DesignWe used a mixed longitudinal design to estimate nutrient intake via 24-h recall and dietary questionnaires among 1299 Tsimane (aged 30-91 y) and 229 Moseten (aged 30-84 y) men and women. We constructed population-level estimates of energy intake, dietary diversity, and nutrient shortfalls and analyzed dietary changes over time and space using multilevel models. Last, we compared Tsimane and Moseten dietary profiles with those of Americans (NHANES).ResultsThe Tsimane diet was characterized by high energy (2422-2736 kcal/d), carbohydrate (376-423 g/d), and protein (119-139 g/d) intakes; low fat intake (40-46 g/d); and low dietary diversity relative to the average US diet. Most calories (64%) were derived from complex carbohydrates. Total energy and carbohydrate intake increased significantly during the 5-y study, particularly in villages near market towns. Tsimane consumption of food additives (lard, oil, sugar, salt) increased significantly [sugar (15.8 g ⋅ person-1 ⋅ d-1) and oil (4.9 mL ⋅ person-1 ⋅ d-1)] between 2010 and 2015. The more-acculturated Moseten consumed substantially more sugar (by 343%) and oil (by 535%) than the Tsimane.ConclusionsA high-energy diet rich in complex carbohydrates is associated with low cardiovascular disease risk when coupled with a physically active lifestyle. A transition away from a high-fiber and low-fat, low-salt, and low-processed-sugar diet is a salient health risk for transitioning populations. Evidence of a nutrition transition in Bolivia parallels trends of increasing body fat and body mass index, which suggests that a low prevalence of cardiovascular disease may not persist.

The Nova classification of ultra-processed foods (UPFs) rests on poorly defined food processes and the presence of food additives from a chemically heterogeneous group, easily leading to misclassification. UPFs are claimed to promote overconsumption of energy and obesity due to high palatability, but little evidence supports effects beyond those that can be accounted for by nutrient composition, energy density, and food matrices. Observational studies link dietary intake of UPFs with obesity, but none have demonstrated independent associations after controlling for likely confounders. A highly cited randomized controlled feeding study that compared a UPF diet with an unprocessed diet showed a rapidly weaning effect on energy intake that can be entirely explained by more conventional and quantifiable dietary factors, including energy density, intrinsic fiber, glycemic load, and added sugar. Clearly, many aspects of food processing can affect health outcomes, but conflating them into the notion of ultra-processing is unnecessary, because the main determinants of chronic disease risk are already captured by existing nutrient profiling systems. In conclusion, the Nova classification adds little to existing nutrient profiling systems; characterizes several healthy, nutrient-dense foods as unhealthy; and is counterproductive to solve the major global food production challenges. [ABSTRACT FROM AUTHOR]

Background Chronic constipation is a prevalent disorder that remains challenging to treat. Studies suggest increasing fiber intake may improve symptoms, although recommendations on the fiber type, dose, and treatment duration are unclear. Objectives We investigated the effects of fiber supplementation on stool output, gut transit time, symptoms, and quality of life in adults with chronic constipation via a systematic review and meta-analysis of randomized controlled trials (RCTs). Methods Studies were identified using electronic databases, backward citation, and hand searches of abstracts. RCTs reporting administration of fiber supplementation in adults with chronic constipation were included. Risks of bias (RoB) was assessed with the Cochrane RoB 2.0 tool. Results were synthesized using risk ratios (RRs), mean differences, or standardized mean differences (SMDs) and 95% CIs using a random-effects model. Results Sixteen RCTs with 1251 participants were included. Overall, 311 of 473 (66%) participants responded to fiber treatment and 134 of 329 (41%) responded to control treatment [RR: 1.48 (95% CI: 1.17, 1.88; P  = 0.001); I2 = 57% (P  = 0.007)], with psyllium and pectin having significant effects. A higher response to treatment was apparent in fiber groups compared to control groups irrespective of the treatment duration, but only with higher fiber doses (>10 g/d). Fiber increased stool frequency [SMD: 0.72 (95% CI: 0.36, 1.08; P  = 0.0001); I2 = 86% (P  < 0.00001)]; psyllium and pectin had significant effects, and improvement was apparent only with higher fiber doses and greater treatment durations (≥4 weeks). Fiber improved stool consistency (SMD: 0.32; 95% CI: 0.18, 0.46; P  < 0.0001), particularly with higher fiber doses. Flatulence was higher in fiber groups compared to control groups(SMD: 0.80; 95% CI: 0.47, 1.13; P  < 0.00001). Conclusions Fiber supplementation is effective at improving constipation. Particularly, psyllium, doses >10 g/d and treatment durations of at least 4 weeks appear optimal, though caution is needed when interpreting the results due to considerable heterogeneity. These findings provide promising evidence on the optimal type and regime of fiber supplementation, which could be used to standardize recommendations to patients. The protocol for this review is registered at PROSPERO as CRD42020191404. [ABSTRACT FROM AUTHOR]

Background: For over 45 y increasingly comprehensive food tables of glycemic index (GI) and glycemic load (GL) have been published in the American Journal of Clinical Nutrition to determine the GI and GL values of diets. Recently the WHO based on a 2019 series of meta-analyses concluded that increases in dietary fiber and whole grains but not reduction in GI or GL warranted recommendations for chronic disease reduction., Methods and Results: We therefore provide a perspective on the current evidence that indicates that GI and GL are also determinants of risk of chronic disease outcomes. We are also concerned with the term dietary fiber used in the singular when there are many dietary fibers that may differ in their physiological effects. Furthermore, the term "whole grains" that refers to "whole grain flour" limits the exploration of "intact" grains that are low GI and have useful physiological effects., Conclusion: We conclude that all these determinants of the health values of carbohydrate-rich foods should be used in combination to assess the health value of carbohydrate-rich foods., Competing Interests: Conflict of interest DJAJ’s wife has previously been a director of INQUIS, which is responsible for clinical studies and GI testing. WCW declares that he has no conflict of interest to declare for this article., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

Background The increasing colorectal cancer (CRC) survivor population highlights the need for dietary recommendations in order to enhance health-related quality of life (HRQoL) and alleviate symptoms of fatigue, chemotherapy-induced peripheral neuropathy (CIPN), and gastrointestinal problems. Objectives Because of the therapeutic potential of dietary fiber on the gut, we aim to assess longitudinal associations of postdiagnostic dietary fiber, fruit, and vegetable intake, a major source of dietary fiber, with HRQoL, fatigue, CIPN, and gastrointestinal symptoms in CRC survivors from 6 wk to 24 mo posttreatment. Methods In a prospective cohort among stage I–III CRC survivors (n = 459), 5 repeated study measurements between diagnosis and 24 mo posttreatment were executed. Dietary fiber intake and fruit and vegetable intake were measured by 7-d dietary records. HRQoL, fatigue, CIPN, and gastrointestinal symptoms were measured by validated questionnaires. We applied confounder-adjusted linear mixed models to analyze longitudinal associations from 6 wk until 24 mo posttreatment and used hybrid models to disentangle the overall association into intraindividual changes and interindividual differences over time. Results Higher dietary fiber intake and fruit and vegetable intake were longitudinally associated with statistically significant better physical functioning and less fatigue. Intraindividual analyses showed that an increase of 10 g/d in dietary fiber within individuals over time was associated with better physical functioning (β: 2.3; 95% CI: 0.1, 4.4), role functioning (ability to perform daily activities; 5.9; 1.5, 10.3), and less fatigue (−4.1; −7.7, −0.5). An average increase in fruit and vegetable intake of 100 g/d between individuals over time was predominantly associated with less fatigue (−2.2; −4.2, −0.3). No associations were found with CIPN and gastrointestinal symptoms. Conclusions Our results suggest that increasing dietary fiber, fruit, and vegetable intake is related to better physical and role functioning and less fatigue in the first 2 y after the end of treatment for CRC. [ABSTRACT FROM AUTHOR]

Background Epidemiological evidence remains conflicting regarding diet and risk of lung cancer. Objectives We sought to systematically investigate whether dietary factors are associated with the risk of incident lung cancer in the UK Biobank. Methods A total of 416,588 participants (54% women) from the UK Biobank were included in the present study. Based on baseline data from FFQs, 3 main dietary patterns were identified by using principal component analysis. Cox proportional hazards models were used to investigate the association of individual food groups and dietary patterns with lung cancer risk. Results During a median follow-up of 7.13 y, 1782 incident lung cancer cases were documented. The association analysis showed high intake of red meat and processed meat was associated with an increased risk of lung cancer (HRper 50 g/d: 1.36; 95% CI: 1.13, 1.65 for red meat; HRper 25 g/d: 1.30; 95% CI: 1.10, 1.53 for processed meat). However, the consumption of fruits (HRper 100 g/d: 0.90; 95% CI: 0.84, 0.95), vegetables (HRper 100 g/d: 0.89; 95% CI: 0.81, 0.99), breakfast cereals (HRper 50 g/d: 0.81; 95% CI: 0.74, 0.89), and dietary fiber (HRper 5 g/d: 0.76; 95% CI: 0.69, 0.84) was inversely associated with the risk of lung cancer. For the dietary pattern analysis [quartile (Q) comparison], high adherence to the Prudent pattern (HRQ4 compared with Q1: 0.84; 95% CI: 0.73, 0.96) was associated with a lower risk of lung cancer, whereas the Western pattern (HRQ4 compared with Q1: 1.27; 95% CI: 1.11, 1.46) was associated with a higher risk of lung cancer. Conclusions Our study indicated that a diet characterized by high intake of fruits, vegetables, breakfast cereals, and dietary fiber, as well as low intake of red meat and processed meat, was associated with a lower risk of lung cancer. [ABSTRACT FROM AUTHOR]

Over recent decades, a number of studies have revealed the possible role of different types of diets, as well as the nutritional elements they are made up of, in the pathogenesis of chronic obstructive pulmonary disease (COPD). To date, dietary factors have been identified to play a role in the prevention of COPD, with evidence from antioxidant nutrients, vitamins, and fiber intake. Additionally, certain dietary patterns such as the Mediterranean diet, together with other Western diets, provide evidence of the influence on COPD development, promoting lung health through nutritional approaches, and giving us an opportunity for intervention. The effect of diet on COPD is conveyed by 3 mechanisms: regulation of inflammation, oxidative stress, and carbon dioxide produced/oxygen intake. Current advances have begun to highlight the possible role of diet in modifying gene expression in certain individuals that predisposes them to COPD through epigenetic modifications. The relation between dietary intake and epigenetic factors has therefore outlined nutriepigenomics as a possible missing link in the relation between environmental exposure to smoke and the appearance of a subsequent chronic bronchial obstruction. This review summarizes the evidence regarding the influence of dietary patterns and nutrients and epigenetic regulatory mechanisms on COPD development and prevention with the aim of encouraging clinical research on the impact of dietary modifications on COPD-related clinical outcomes. This review highlights the importance of proposing and carrying out future studies focused on the modulating effects of certain nutrients on epigenetic changes in patients with specific COPD phenotypes (bronchiectasis, emphysema, asthma/COPD, chronic bronchitis), and their individual responses to cigarette smoking, environmental pollution, or other noxious particles. The objectives of these future studies must be directed to the development of novel therapeutic approaches and personalized management of COPD. [ABSTRACT FROM AUTHOR]

Background: Older adults living in residential care facilities are commonly given laxatives to treat constipation; however, these may not always provide full relief, and side effects include diarrhea. Dietary fiber effectively prevents constipation, and international guidelines recommend 25 g/d for optimal laxation. Older adults in residential care rely on the facility menu to provide their nutritional requirements, including adequate dietary fiber. Little is known about how much dietary fiber is provided and consumed., Objectives: We aimed to determine the provision and consumption of dietary fiber for older adults living in residential care facilities., Methods: We systematically searched available literature for studies reporting the analysis of residential care menus and meals consumed by residents aged over 65 y. A meta-analysis was performed on the studies that provided the mean amount of dietary fiber provided and consumed by residents. A random effect model was applied due to the heterogeneity of study methodologies., Results: The literature search yielded 4406 publications, but only 28 studies were eligible for our meta-analysis. The study sample comprised 4817 residents. The mean amount of fiber provided to residents was 21.4 g/d [standard error (SE): 1.2; 95% confidence interval: 18.8, 24.2 g/d], the mean amount of fiber consumed by residents was 15.8 g/d (SE: 0.6; 95% confidence interval: 14.7, 16.9 g/d)., Conclusions: Older adults living in care facilities are provided with dietary fiber below the recommended guidelines. Compounding this is that residents consume much less than what is provided and do not meet the recommendations for dietary fiber consumption. There is scope to improve dietary fiber provision, promote consumption to residents to aid laxation, and potentially reduce laxative use and the unwanted side effects of diarrhea. This trial was registered at PROSPERO as CRD42023427265., (Copyright © 2024 American Society for Nutrition. Published by Elsevier Inc. All rights reserved.)

Background A growing body of literature suggests chronically higher bile acid (BA) concentrations may be associated with multiple health conditions. Diet may affect BA metabolism and signaling; however, evidence from human populations is lacking. Objectives We systematically investigated cross-sectional associations of a priori–selected dietary components (fiber, alcohol, coffee, fat) with circulating BA concentrations. Methods We used targeted, quantitative LC-MS/MS panels to measure 15 circulating BAs in a subset of the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study (ATBC; n  = 2224) and Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO; n  = 986) comprising Finnish male smokers and United States men and women, respectively. We used multivariable linear regression to estimate associations of each dietary component with log-transformed BAs; exponentiated coefficients estimate proportional differences. We included the median of the dietary component quartile in linear regression models to test for trend. Results In ATBC, fiber was inversely associated with multiple circulating BAs. The proportional difference was –10.09% (95% CI: −19.29 to 0.16; P- trend = 0.04) when comparing total BAs among those in the highest relative to the lowest fiber quartile. Alcohol, trans fat, and polyunsaturated fat were positively associated with BAs in ATBC. The proportional difference comparing total BAs among those in the highest relative to the lowest alcohol quartile was 8.76% (95% CI: –3.10 to 22.06; P- trend = 0.03). Coffee and monounsaturated fat were inversely associated with BAs. The proportional difference comparing total BAs among those in the highest relative to the lowest coffee quartile was –24.03% (95% CI: –31.57 to –15.66; P- trend < 0.0001). In PLCO, no dietary components were associated with BAs except fiber, which was inversely associated with tauroursodeoxycholic acid. Conclusions Alcohol, coffee, certain fat subtypes, and fiber were associated with circulating concentrations of multiple BAs among Finnish male smokers. Given the potential role of BAs in disease risk, further investigation of the effects of diet on BAs in humans is warranted. [ABSTRACT FROM AUTHOR]

Background Lifestyle interventions are the first-line treatment for obesity, but participant weight loss is typically low. Objectives We evaluated the efficacy of an alternative lifestyle intervention [Healthy Weight for Living (HWL)] compared with a modified Diabetes Prevention Program (m-DPP). HWL was based on a revised health behavior change model emphasizing hunger management and the development of healthy food preferences. m-DPP was a standard Diabetes Prevention Program implemented with counselor time matched to HWL. Participants were adult dependents of military personnel and had overweight or obesity. Methods Participants were randomly assigned to HWL (n  = 121) or m-DPP (n  = 117), delivered primarily by group videoconference with additional midweek emails. The primary outcome was 12-mo weight change. Secondary outcomes included 6-mo changes in cardiometabolic risk factors and diet. Intention-to-treat (ITT) and complete case (CC) analyses were performed using linear mixed models. Results Retention did not differ between groups (72% and 66% for HWL and m-DPP at 12 mo, respectively; P  = 0.30). Mean ± SE adjusted 12-mo weight loss in the ITT cohort was 7.46 ± 0.85 kg for HWL and 7.32 ± 0.87 kg for m-DPP (P  = 0.91); in the CC cohort, it was 7.83 ± 0.82 kg for HWL and 6.86 ± 0.88 kg for m-DPP (P  = 0.43). Thirty-eight percent of HWL and 30% of m-DPP completers achieved ≥10% weight loss (P  = 0.32). Improvements in systolic blood pressure, LDL cholesterol, triglycerides, fasting glucose, general health, sleep, and mood were similar across groups; improvements in diastolic blood pressure were greater in m-DPP. Adjusted group mean reductions in energy intake were not significantly different between groups, but HWL participants were more adherent to their dietary prescription for lower glycemic index and high fiber and protein (P  = 0.05 to <0.001 for ITT). Conclusions HWL and m-DPP showed equivalent and clinically impactful mean weight loss with cardiometabolic benefits. These results identify an alternative approach for behavioral treatment of overweight and obesity. This trial was registered at clinicaltrials.gov as NCT02348853. [ABSTRACT FROM AUTHOR]

Background Accurate estimates of the usual intake of nutrients are important for monitoring nutritional adequacy and diet quality of populations. In Canada, comprehensive, nationally representative nutrient estimates have not been available since the Canadian Community Health Survey (CCHS)–Nutrition 2004 survey. Objective The objective of this research was to assess nutrient intakes, distributions, and adequacy of the intakes of Canadian adults. Methods Participants' first 24-h dietary recall, and the second-day recall from a subset of participants from the recently released CCHS 2015 Public Use Microdata File (PUMF) were used to estimate usual intakes of macronutrients, vitamins, and minerals in adults [≥19 y, excluding lactating females and those with invalid energy intake (EI)]. Usual intakes by DRI age-sex groups were estimated using the National Cancer Institute method, adjusted for age, sex, misreporting status, weekend/weekday, and sequence of recall analyzed (first/second) with outliers removed (final sample, n  = 11,992). Usual intakes from food were assessed for prevalence of inadequacy in relation to DRI recommendations. Results Canadian macronutrient intakes were within the recommended acceptable macronutrient distribution ranges. EI was 2154 kcal/d for males (19+) and 1626 kcal/d for females (19+). A high prevalence of inadequate intakes was seen for vitamin A (>47%), vitamin D (>94%), vitamin C (>29% for nonsmokers and >59% for smokers), magnesium (>45%), and calcium (>44%), whereas <25% and <40% of adults (19+) had intakes above the adequate intake for fiber and potassium, respectively. Canadians continue to consume sodium in excess of recommendations (74.8% of males and 47.6% of females). Conclusions A significant number of Canadian adults may not be meeting recommendations for several essential nutrients, contributing to nutrient inadequacies. These results highlight the nutrients of concern by specific age-sex groups that may be important for public health interventions aimed at improving diet quality and nutrient adequacy for Canadian adults. [ABSTRACT FROM AUTHOR]

Background Obesity-associated low-grade inflammation contributes to the development of cardiovascular disease (CVD). Apples are rich in anti-inflammatory bioactives including polyphenols and fiber. Objectives We aimed to determine the effects of regular apple consumption on fasting plasma biomarkers of inflammation (primary outcome), endotoxemia, carbohydrate and lipid metabolism (glucose, insulin, triacylglycerol; secondary outcomes), and peripheral blood mononuclear cell (PBMC)-secreted cytokines (secondary outcome) in individuals with overweight and obesity. Methods A randomized, controlled, parallel-arm trial was conducted with n  = 46 participants. After avoiding foods and beverages rich in polyphenols and fiber for 2 wk, participants consumed 3 whole Gala apples (∼200 g edible parts)/d as part of their habitual diet (n  = 23) or avoided apples (control, n  = 23) for 6 wk. All participants limited consumption of polyphenols and fiber during the 6-wk trial. Fasting blood samples were collected before and after 6 wk for analysis of plasma biomarkers and isolation of PBMCs, which were cultured for 24 h unstimulated or stimulated with LPS (10 ng/mL). Results Forty-four participants completed the trial (30 female, 14 male; mean ± SEM age: 45.4 ± 2.2 y; BMI: 33.4 ± 0.9 kg/m2). After ANCOVA and correcting for multiple comparisons, apples decreased fasting plasma C-reactive protein by 17.0% (range: 14.3%–19.6%, P =  0.005), IL-6 by 12.4% (range: 6.7%–17.5%, P <  0.001), and LPS-binding protein by 20.7% (range: 14.1%–26.4%, P <  0.001) compared with control. Apples also decreased PBMC-secreted IL-6 by 28.3% (range: 22.4%–33.5%, P <  0.001) and IL-17 by 11.0% (range 5.8–15.6%, P =  0.003) in the unstimulated condition compared with control. Exploratory analysis showed apples also increased plasma total antioxidant capacity by 9.6% (range: 1.7–18.9%, P =  0.002) compared with control. However, apples had no effect on anthropometric or other CVD risk markers. Conclusions Six-week daily whole Gala apple consumption may be an effective dietary strategy to mitigate the obesity-associated inflammation that exacerbates CVD risk, without weight loss. This trial was registered at clinicaltrials.gov as NCT03523403. [ABSTRACT FROM AUTHOR]

Background Diet has a major influence on the human gut microbiota, which has been linked to health and disease. However, epidemiological studies on associations of a healthy diet with the microbiota utilizing a whole-diet approach are still scant. Objectives To assess associations between healthy food choices and human gut microbiota composition, and to determine the strength of association with functional potential. Methods This population-based study sample consisted of 4930 participants (ages 25–74; 53% women) in the FINRISK 2002 study. Intakes of recommended foods were assessed using a food propensity questionnaire, and responses were transformed into healthy food choices (HFC) scores. Microbial diversity (alpha diversity) and compositional differences (beta diversity) and their associations with the HFC score and its components were assessed using linear regression. Multiple permutational multivariate ANOVAs were run from whole-metagenome shallow shotgun–sequenced samples. Associations between specific taxa and HFC were analyzed using linear regression. Functional associations were derived from Kyoto Encyclopedia of Genes and Genomes orthologies with linear regression models. Results Both microbial alpha diversity (β/SD, 0.044; SE, 6.18 × 10−5; P  = 2.21 × 10−3) and beta diversity (R 2, 0.12; P  ≤ 1.00 × 10−3) were associated with the HFC score. For alpha diversity, the strongest associations were observed for fiber-rich breads, poultry, fruits, and low-fat cheeses (all positive). For beta diversity, the most prominent associations were observed for vegetables, followed by berries and fruits. Genera with fiber-degrading and SCFA-producing capacities were positively associated with the HFC score. The HFC score was associated positively with functions such as SCFA metabolism and synthesis, and inversely with functions such as fatty acid biosynthesis and the sulfur relay system. Conclusions Our results from a large, population-based survey confirm and extend findings of other, smaller-scale studies that plant- and fiber-rich dietary choices are associated with a more diverse and compositionally distinct microbiota, and with a greater potential to produce SCFAs. [ABSTRACT FROM AUTHOR]

Background SCFAs are involved in regulation of body weight and bone health. Objectives We aimed to examine whether genetic variations related to butyrate modified the relation between dietary fiber intake and changes in bone mineral density (BMD) in response to weight-loss dietary interventions. Methods In the 2-y Preventing Overweight Using Novel Dietary Strategies trial, 424 participants with BMD measured by DXA scan were randomly assigned to 1 of 4 diets varying in macronutrient intakes. A polygenic score (PGS) was calculated based on 7 genetic variants related to the production of butyrate for 370 of the 424 participants. Results SCFA PGS significantly modified the association between baseline dietary fiber intake and sex on 2-y changes in whole-body BMD (P- interaction = 0.049 and 0.008). In participants with the highest tertile of SCFA PGS, higher dietary fiber intake was related to a greater increase in BMD (β:  0.0022; 95% CI: 0.0009, 0.0035; P  = 0.002), whereas no such association was found for participants in the lower tertiles. In the lowest tertiles of SCFA PGS, men showed a significant increase in whole-body BMD (β: 0.0280; 95% CI: 0.0112, 0.0447; P  = 0.002) compared with women. In the highest tertile, no significant difference was found for the change in BMD between men and women. Conclusions Our data indicate that genetic variants related to butyrate modify the relations of dietary fiber intake and sex with long-term changes in BMD in response to weight-loss diet interventions. [ABSTRACT FROM AUTHOR]

Background Inflammatory bowel disease (IBD) may impact the extent to which food, eating, and drinking bring satisfaction and enjoyment to peoples' lives, and this may impact dietary intake. The prevalence of an impaired food-related quality of life (FR-QoL), its associated factors, and its impact on diet have not been explored. Objectives To measure the prevalence and nature of the burden of impaired FR-QoL in people with IBD, the factors associated with these, and their associations with nutrient intake. Methods We recruited 1576 outpatients with IBD (≥16 years old) in person from 7 IBD centers across the United Kingdom. Patients completed validated questionnaires to measure their FR-QoL, quality of life (QoL), distress, fatigue, anxiety, and depression. Dietary intake was recorded using the European Prospective Investigation into Cancer FFQ. A health professional recorded disease activity, Montreal classification, blood results, BMI, and malnutrition risk. FR-QoL was regressed onto explanatory variables using univariable and multivariable analyses. Results Data from 1221 patients were available (77.4% response; Crohn's disease, 65%; ulcerative colitis, 35%). The FR-QoL mean (± SD) score was 80.8 ± 26.9, with wide ranges (minimum, 29; maximum, 145). Following multivariable regression, the strongest associations with FR-QoL were the number of recent disease flares (5 flares β = −12.7; P  < 0.001), the IBD-specific QoL (β = 0.33; P  < 0.001), and IBD-related distress (β = −0.26; P  < 0.001). Patients with poorer FR-QoL had lower intakes of fiber (nonstarch polysaccharide; Q1 to Q5 difference = 2.1 g/d; 95% CI: 0.4–3.8; P  = 0.048), calcium (192.6 mg/d; 95% CI: 112.5–272.6; P  < 0.001), phosphorus (167 mg/d; 95% CI: 58–276; P  = 0.041), and magnesium (34.4 mg/d; 95% CI: 9.3–59.4; P  = 0.041). Conclusions Impaired FR-QoL is prevalent in IBD and is associated with recurrent disease flares, a reduced IBD-specific QoL, and greater IBD-related distress. A poorer FR-QoL was associated with lower intakes of key nutrients of importance to IBD, including those relating to gut health and bone mineralization. [ABSTRACT FROM AUTHOR]

Background A processed diet, high in fat and low in fiber, is associated with differences in the gut microbiota and adverse health outcomes in humans; however, little is known about the diet–microbiota relation and its impact on pregnancy. Spontaneous preterm birth (SPTB), a pregnancy outcome with serious short- and long-term consequences, occurs more frequently in black and in obese women in the United States. Objectives In a prospective, case-control sample matched for race and obesity (cases = 16, controls = 32), we compared the fecal gut microbiota, fecal and plasma metabolites, and diet in the late second trimester. We hypothesized that a Western diet would be associated with reduced microbiota richness and a metabolic signature predicting incidence of SPTB. Methods The fecal microbiota was characterized by 16S-tagged sequencing and untargeted metabolomics was used to analyze both plasma and fecal metabolites. Wilcoxon's rank-sum test was used for the comparison of microbiota genera, α-diversity, fecal and plasma metabolites, and dietary variables between term and SPTB. β-Diversity was analyzed using permutational multivariate ANOVA, and metabolite associations were assessed by module analysis. Results A decrease in α-diversity was strongly associated with the development of SPTB, especially in the taxonomic class of Betaproteobacteria. Of 824 fecal metabolites, 22 metabolites (mostly lipids) differed between cases and controls (P  < 0.01), with greater DHA (22:6n–3) and EPA (20:5n–3) in cases [false discovery rate (FDR) < 0.2]. The most significant fecal metabolite module (FDR-adjusted P  = 0.008) was dominated by DHA and EPA. Dietary saturated fat (primarily palmitate) intake was greater in cases (31.38 ± 7.37 compared with 26.08 ± 8.62 g, P  = 0.045) and was positively correlated with fecal DHA and EPA (P  < 0.05). Conclusions Reduced α-diversity of the gut microbiota and higher excretion of omega-3 (n–3) fatty acids in stool may provide a novel biomarker signature predicting SPTB in women with a low-fiber, high-fat diet. Further investigation of these markers in a larger sample is needed for validation. [ABSTRACT FROM AUTHOR]

Background Gut microbiota composition as influenced by long-term diet may be associated with the risk of adult chronic diseases. Thus, establishing the relation of long-term diet, particularly starting from early life, with adult microbiota composition would be an important research advance. Objective We aimed to investigate the association of long-term intake of energy, carbohydrate, fiber, protein, and fat from infancy to late adolescence with microbiota composition in adulthood. Methods Within the prospective DOrtmund Nutritional and Anthropometric Longitudinally Designed (DONALD) Study, we sampled stool 1 or 2 times within 1 y from 128 adults (median age: 29 y). Microbiota composition was profiled by 16S ribosomal RNA sequencing. Annual dietary records from age 1 to 18 y were retrieved. We estimated trajectories of energy, energy-adjusted carbohydrate, fiber, protein, and fat intake with multilevel models, producing predicted intake at age 1 y and rates of change in intake. A multivariate, zero-inflated, logistic-normal model was used to model the association between intake trajectories and the composition of 158 genera in single-sampled individuals. Associations found in this model were confirmed in double-sampled individuals using a zero-inflated Beta regression model. Results Adjusting for covariates and temporal differences in microbiota composition, long-term carbohydrate intake was associated with 3 genera. Specifically, carbohydrate intake at age 1 y was negatively associated with Phascolarctobacterium [coefficient = −4.31; false discovery rate (FDR)–adjusted P  = 0.006] and positively associated with Dialister (coefficient = 3.06; FDR-adjusted P  = 0.003), and the rate of change in carbohydrate intake was positively associated with Desulfovibrio (coefficient = 13.16; FDR-adjusted P  = 0.00039). Energy and other macronutrients were not associated with any genus. Conclusions This work links long-term carbohydrate intake to microbiota composition. Considering the associations of high carbohydrate intake and microbiota composition with some diseases, these findings could inform the development of gut microbiota–targeted dietary recommendations for disease prevention. [ABSTRACT FROM AUTHOR]

Background Yogurt is a commonly consumed fermented food. Regular yogurt consumption may contribute to a favorable gut microbiome and gut health, but few epidemiologic studies have considered the relation between regular yogurt consumption and the incidence of and mortality from colorectal cancer. Objectives We used data from 2 large, prospective cohort studies, the Nurses' Health Study and the Health Professionals Follow-Up Study, to examine the role of yogurt consumption on colorectal cancer incidence and mortality. Methods During 32 years of follow-up in 83,054 women (mean age at baseline, 45.7 years) and 26 years of follow-up in 43,269 men (mean age at baseline, 52.3 years), we documented a total of 2666 newly diagnosed cases of colorectal cancer in these cohorts. We modeled yogurt consumption at baseline and cumulatively updated it throughout follow-up. Results: Baseline yogurt consumption was associated with a reduced risk of colon cancer in age-adjusted analyses (P for trend < 0.001). Associations remained statistically significant after adjusting for potential confounders, including calcium and fiber intake (P for trend = 0.03), and were restricted to proximal colon cancer. The consumption of 1 + servings per week of yogurt at baseline, compared to no yogurt consumption, was associated with a multivariable HR of 0.84 (95% CI, 0.70–0.99; P trend = 0.04) for the proximal colon cancer incidence. Latency analyses suggested that the most important window of opportunity for regular yogurt consumption to prevent colorectal cancer was 16–20 years in the past. When yogurt consumption was cumulatively updated, associations attenuated and were no longer significant. No statistically significant inverse trend was observed between yogurt consumption and the colorectal cancer mortality. Conclusions In these large cohorts, the frequency of yogurt consumption was associated with a reduced risk of proximal colon cancer with a long latency period. No significant inverse trend was observed for colorectal cancer mortality. [ABSTRACT FROM AUTHOR]

Background Higher intakes of whole grains and dietary fiber have been associated with lower risk of insulin resistance, hyperinsulinemia, and inflammation, which are known predisposing factors for cancer. Objectives Because the evidence of association with bladder cancer (BC) is limited, we aimed to assess associations with BC risk for intakes of whole grains, refined grains, and dietary fiber. Methods We pooled individual data from 574,726 participants in 13 cohort studies, 3214 of whom developed incident BC. HRs, with corresponding 95% CIs, were estimated using Cox regression models stratified on cohort. Dose–response relations were examined using fractional polynomial regression models. Results We found that higher intake of total whole grain was associated with lower risk of BC (comparing highest with lowest intake tertile: HR: 0.87; 95% CI: 0.77, 0.98; HR per 1-SD increment: 0.95; 95% CI: 0.91, 0.99; P for trend: 0.023). No association was observed for intake of total refined grain. Intake of total dietary fiber was also inversely associated with BC risk (comparing highest with lowest intake tertile: HR: 0.86; 95% CI: 0.76, 0.98; HR per 1-SD increment: 0.91; 95% CI: 0.82, 0.98; P for trend: 0.021). In addition, dose–response analyses gave estimated HRs of 0.97 (95% CI: 0.95, 0.99) for intake of total whole grain and 0.96 (95% CI: 0.94, 0.98) for intake of total dietary fiber per 5-g daily increment. When considered jointly, highest intake of whole grains with the highest intake of dietary fiber showed 28% reduced risk (95% CI: 0.54, 0.93; P for trend: 0.031) of BC compared with the lowest intakes, suggesting potential synergism. Conclusions Higher intakes of total whole grain and total dietary fiber are associated with reduced risk of BC individually and jointly. Further studies are needed to clarify the underlying mechanisms for these findings. [ABSTRACT FROM AUTHOR]

Background Obesity prevalence remains high in the United States, and there is an increased risk among women who do not lose their gestational weight gain during the postpartum period. Indicators of dietary carbohydrate quality including added sugar consumption, glycemic load, and glycemic index have been linked with weight gain, whereas fiber may protect against obesity. However, these dietary factors have not been examined during the postpartum period. Objectives The aim of this study was to determine whether dietary sugars and fiber intake were associated with changes in postpartum weight. Methods We examined Hispanic women from the longitudinal Southern California Mother's Milk Study (n  = 99) at 1 and 6 mo postpartum. Maternal assessments included height, weight, and dietary intake based on 24-h diet recalls. We used multivariable linear regression to examine the relation between maternal diet and change in postpartum weight after adjusting for maternal age, height, and energy intake. Results Higher intake of added sugar was associated with postpartum weight gain (β: 0.05; 95% CI: 0.004, 0.10; P  = 0.05). In addition, a half 8-ounce (8 fluid ounces = 236.6 mL) serving per day increase in soft drinks was associated with a 1.52-kg increase in weight (95% CI: 0.70, 2.34 kg; P  < 0.001). A high glycemic index (β: 0.25; 95% CI: 0.07, 0.42; P  = 0.006) and glycemic load (β: 0.04; 95% CI: 0.002, 0.08; P  = 0.04) were associated with postpartum weight gain. Higher soluble fiber was associated with a decrease in postpartum weight (β: −0.82 kg; 95% CI: −1.35, −0.29 kg; P  = 0.003) and the negative effects of added sugar, sugary beverages, and high-glycemic-index and -load diets were partially attenuated after adjusting for soluble fiber intake. Conclusions Increased consumption of added sugar, sugar-sweetened beverages, and high-glycemic diets were associated with greater weight gain in the first 6 mo postpartum. In addition, increased consumption of soluble fiber was associated with postpartum weight loss, which may partially offset the obesogenic effects of some dietary sugars. [ABSTRACT FROM AUTHOR]

Background Wheat bran, nopal, and psyllium are examples of particulate, viscous and particulate, and viscous fibers, respectively, with laxative properties yet contrasting fermentability. Objectives We assessed the fermentability of these fibers in vitro and their effects on intestinal function relevant to laxation in vivo using MRI. Methods Each fiber was predigested prior to measuring gas production in vitro during 48-h anaerobic incubation with healthy fecal samples. We performed a randomized, 3-way crossover trial in 14 healthy volunteers who ingested 7.5 g fiber twice on the day prior to study initiation and once with the study test meal. Serial MRI scans obtained after fasting and hourly for 4 h following meal ingestion were used to assess small bowel water content (SBWC), colonic volumes, and T1 of the ascending colon (T1AC) as measures of colonic water. Breath samples for hydrogen analysis were obtained while patients were in the fasted state and every 30 min for 4 h following meal ingestion Results In vitro, the onset of gas production was significantly delayed with psyllium (mean ± SD: 14 ± 5 h) compared with wheat bran (6 ± 2 h, P  = 0.003) and was associated with a smaller total gas volume (P  = 0.01). Prefeeding all 3 fibers for 24 h was associated with an increased fasting T1AC (>75% of values >90th centile of the normal range). There was a further rise during the 4 h after psyllium (0.3 ± 0.3 s P  = 0.009), a fall with wheat bran (−0.2 ± 0.2 s; P  = 0.02), but no change with nopal (0.0 ± 0.1 s, P  = 0.2). SBWC increased for all fibers; nopal stimulated more water than wheat bran [AUC mean (95% CI) difference: 7.1 (0.6, 13.8) L/min, P  = 0.03]. Breath hydrogen rose significantly after wheat bran and nopal but not after psyllium (P  < 0.0001). Conclusion Both viscous and particulate fibers are equally effective at increasing colonic T1 over a period of 24 h. Mechanisms include water trapping in the small bowel by viscous fibers and delivery of substrates to the colonic microbiota by more fermentable particulate fiber. This trial was registered at clinicaltrials.gov as NCT03263065. [ABSTRACT FROM AUTHOR]

Background Whole grains and other foods containing fiber are thought to be inversely related to colorectal cancer (CRC). However, whether these associations reflect fiber or fiber source remains unclear. Objectives We evaluated associations of whole grain and dietary fiber intake with CRC risk in the large NIH-AARP Diet and Health Study. Methods We used Cox proportional hazard models to estimate HRs and 95% CIs for whole grain and dietary fiber intake and risk of CRC among 478,994 US adults, aged 50–71 y. Diet was assessed using a self-administered FFQ at baseline in 1995–1996, and 10,200 incident CRC cases occurred over 16 y and 6,464,527 person-years of follow-up. We used 24-h dietary recall data, collected on a subset of participants, to evaluate the impact of measurement error on risk estimates. Results After multivariable adjustment for potential confounders, including folate, we observed an inverse association for intake of whole grains (HRQ5 vs.Q1 : 0.84; 95% CI: 0.79, 0.90; P -trend < 0.001), but not dietary fiber (HRQ5 vs. Q1: 0.96; 95% CI: 0.88, 1.04; P -trend = 0.40), with CRC incidence. Intake of whole grains was inversely associated with all CRC cancer subsites, particularly rectal cancer (HRQ5 vs. Q1: 0.76; 95% CI: 0.67, 0.87; P -trend < 0.001). Fiber from grains, but not other sources, was associated with lower incidence of CRC (HRQ5 vs. Q1: 0.89; 95% CI: 0.83, 0.96; P -trend < 0.001), particularly distal colon (HRQ5 vs. Q1: 0.84; 95% CI: 0.73, 0.96; P -trend = 0.005) and rectal cancer (HRQ5 vs. Q1: 0.77; 95% CI: 0.66, 0.88; P- trend < 0.001). Conclusions Dietary guidance for CRC prevention should focus on intake of whole grains as a source of fiber. [ABSTRACT FROM AUTHOR]

Background Glycemic load (GL) reflects the quantity and quality of carbohydrates in the diet; dietary fiber and added sugar are components of GL. Few epidemiologic studies have assessed the association between these dietary factors and fecundability. Objective We prospectively evaluated the associations of GL, total carbohydrates, dietary fiber, and added sugar with fecundability. Methods Snart Foraeldre (SF) and Pregnancy Study Online (PRESTO) are parallel web-based prospective preconception cohorts of couples attempting to conceive in Denmark and North America. At baseline, female participants completed a web-based questionnaire on demographic and lifestyle factors and a validated FFQ. We calculated GL, total carbohydrate intake, total dietary fiber, carbohydrate-to-fiber ratio, and added sugar based on reported frequencies for individual foods, standard recipes for mixed foods, and average serving sizes. The analysis included 2709 SF participants and 4268 PRESTO participants. We used proportional probabilities regression models to estimate fecundability ratios (FR) and 95% CIs. Results Compared with an average daily GL of ≤100, FRs for an average daily GL of ≥141 were 0.89 (95% CI: 0.73, 1.08) in SF and 0.87 (95% CI: 0.77, 0.98) in PRESTO participants. Compared with consuming ≤16 g/d of dietary fiber, FRs for consuming ≥25 g/d were 0.99 (95% CI: 0.81, 1.22) in SF and 1.06 (95% CI: 0.94, 1.20) in PRESTO. Compared with a carbohydrate-to-fiber ratio of ≤8, FRs for a ratio of ≥13 were 0.86 (95% CI: 0.73, 1.01) in SF and 0.87 (95% CI: 0.78, 0.98) in PRESTO. Compared with ≤27 g/d of added sugar, FRs for ≥72 g/d were 0.87 (95% CI: 0.68, 1.10) in SF and 0.86 (95% CI: 0.75, 0.99) in PRESTO participants. Conclusions Among women attempting to conceive in Denmark and North America, diets high in GL, carbohydrate-to-fiber ratio, and added sugar were associated with modestly reduced fecundability. [ABSTRACT FROM AUTHOR]

Background Mounting evidence, yet with varying levels of proof, suggests that dietary fibers (DFs) may exert a protective role against various chronic diseases, but this might depend on the DF type and source. Objectives Our objectives were to assess the associations between the intake of DFs of different types [total (TDF), soluble (SF), insoluble (IF)] and from different sources (fruits, vegetables, whole grains, legumes, potatoes and tubers) and the risk of cardiovascular diseases (CVDs), cancer, type 2 diabetes (T2D), and mortality in the large-scale NutriNet-Santé prospective cohort (2009–2019). Methods Overall, 107,377 participants were included. Usual DF intake was estimated from validated repeated 24-h dietary records over the first 2 y following inclusion in the cohort. Associations between sex-specific quintiles of DF intake and the risk of chronic diseases and mortality were assessed using multiadjusted Cox proportional hazards models. Results T2D risk was inversely associated with TDFs [HR for quintile 5 compared with quintile 1: 0.59 (95% CI: 0.42, 0.82), P -trend <0.001], SFs [HR: 0.77 (0.56, 1.08); P -trend = 0.02], and IFs [HR: 0.69 (0.50, 0.96); P -trend = 0.004]. SFs were associated with a decreased risk of CVD [HR: 0.80 (0.66, 0.98); P -trend = 0.01] and colorectal cancer [HR: 0.41 (0.21, 0.79); P -trend = 0.01]. IFs were inversely associated with mortality from cancer or CVDs [HR: 0.65 (0.45, 0.94); P -trend = 0.02]. TDF intake was associated with a decreased risk of breast cancer [HR:: 0.79 (0.54, 1.13); P -trend = 0.04]. DF intake from fruit was associated with the risk of several chronic diseases. Conclusions Our results suggest that DF intake, especially SFs and DFs from fruits, was inversely associated with the risk of several chronic diseases and with mortality. Further studies are needed, involving different types and sources of fiber. Meanwhile, more emphasis should be put on DFs in public health nutrition policies, as DF intake remains below the recommended levels in many countries. This trial was registered at clinicaltrials.gov as NCT03335644. [ABSTRACT FROM AUTHOR]

Background The low intake of dietary fiber compared to recommended amounts has been referred to as the dietary fiber gap. The addition of fiber to snack foods could favorably alter gut microbiota and help individuals meet intake recommendations. Objectives Our objective was to examine the effect of low- and moderate-dose fiber-containing snack bars, comprising mainly chicory root inulin-type fructans (ITF), on gut microbiota in healthy adults with habitual low dietary fiber intake using 16S ribosomal RNA–based approaches. Methods In 2 separate 4-wk, placebo-controlled, double-blind, crossover trials, 50 healthy adults with low dietary fiber intake were randomly assigned to receive isocaloric snack bars of either moderate-dose fiber (7 g/d) or control in Trial 1 (n  = 25) or low-dose fiber (3 g/d) or control in Trial 2 (n  = 25), with 4-wk washout periods. Fecal microbiota composition and inferred function, fecal SCFA concentration, gastrointestinal (GI) symptoms, dietary intake, and quality of life were measured. Results Compared with the control group, the moderate-dose group showed significant differences across multiple microbial taxa, most notably an increased relative abundance of the Bifidobacterium genus from (mean ± SEM) 5.3% ± 5.9% to 18.7% ± 15.0%. With low-dose ITF, significant increases in Bifidobacterium were no longer present after correction for multiple comparisons but targeted analysis with qPCR showed a significant increase in Bifidobacterium. Predictive functional profiling identified changes in predicted function after intake of the moderate- but not the low-dose bar. Fecal SCFAs were affected by time but not treatment. There were no between-group differences in GI symptoms. Importantly, fiber intake increased significantly with the moderate- and low-dose bars. Conclusions In healthy adults, adding 3 or 7 g ITF to snack bars increased Bifidobacterium , a beneficial member of the gut microbial community. The addition of ITF to food products could help reduce the dietary fiber gap prevalent in modern life. This trial was registered at clinicaltrials.gov as NCT03042494. [ABSTRACT FROM AUTHOR]

Background Many patients with rheumatoid arthritis (RA) report symptom relief from certain foods. Earlier research indicates positive effects of food and food components on clinical outcomes in RA, but insufficient evidence exists to provide specific dietary advice. Food components may interact but studies evaluating combined effects are lacking. Objectives We aimed to investigate if an anti-inflammatory diet reduces disease activity in patients with RA. Methods In this single-blinded crossover trial, 50 patients with RA were randomly assigned to an intervention diet containing a portfolio of suggested anti-inflammatory foods, or a control diet similar to the general dietary intake in Sweden, for 10 wk. After a 4-mo washout period the participants switched diet. Food equivalent to ∼50% of energy requirements was delivered weekly to their homes. For the remaining meals, they were encouraged to consume the same type of foods as the ones provided during each diet. Primary outcome was change in Disease Activity Score in 28 joints-Erythrocyte Sedimentation Rate (DAS28-ESR). Secondary outcomes were changes in the components of DAS28-ESR (tender and swollen joints, ESR, and visual analog scale for general health) and DAS28-C-reactive protein. Results In the main analysis, a linear mixed ANCOVA model including the 47 participants completing ≥1 diet period, there was no significant difference in DAS28-ESR between the intervention and control periods (P  = 0.116). However, in unadjusted analyses, DAS28-ESR significantly decreased during the intervention period and was significantly lower after the intervention than after the control period in the participants who completed both periods (n  = 44; median: 3.05; IQR: 2.41, 3.79 compared with median: 3.27; IQR: 2.69, 4.28; P  = 0.04, Wilcoxon's Signed Rank test). No significant differences in the components were observed. Conclusions This trial indicates positive effects of a proposed anti-inflammatory diet on disease activity in patients with RA. Additional studies are required to determine if this diet can cause clinically relevant improvements. This trial was registered at clinicaltrials.gov as NCT02941055. [ABSTRACT FROM AUTHOR]

Background An inverse association has been shown between dietary fiber intake and several noncommunicable diseases. However, evidence of this effect remains unclear in the Asian population. Objective We examined the association between dietary fiber intake and all-cause and cause-specific mortality, as well as the association between fiber intake from dietary sources and all-cause mortality. Methods We conducted a large-scale population-based cohort study (Japan Public Health Center-based prospective study). A validated questionnaire with 138 food items was completed by 92,924 participants (42,754 men and 50,170 women) aged 45–74 y. Dietary fiber intake was calculated and divided into quintiles. HR and 95% CI of total and cause-specific mortality were reported. Results During the mean follow-up of 16.8 y, 19,400 deaths were identified. In multivariable adjusted models, total, soluble, and insoluble fiber intakes were inversely associated with all-cause mortality. The HRs of total mortality in the highest quintile of total fiber intake compared with the lowest quintile were 0.77 (95% CI: 0.72, 0.82; P trend <0.0001) in men and 0.82 (95% CI: 0.76, 0.89; P trend <0.0001) in women. Increased quintiles of dietary fiber intake were significantly associated with decreased mortality due to total cardiovascular disease (CVD), respiratory disease, and injury in both men and women, whereas dietary fiber intake was inversely associated with cancer mortality in men but not women. Fiber from fruits, beans, and vegetables, but not from cereals, was inversely associated with total mortality. Conclusion In this large-scale prospective study with a long follow-up period, dietary fiber was inversely associated with all-cause mortality. Since intakes of dietary fiber, mainly from fruits, vegetables, and beans were associated with lower all-cause mortality, these food sources may be good options for people aiming to consume more fiber. [ABSTRACT FROM AUTHOR]

Background Short chain fatty acids (SCFAs; e.g., acetate, propionate, and butyrate) are produced by microbial fermentation of fiber in the colon. Evidence is lacking on how high-fiber diets that differ in macronutrient composition affect circulating SCFAs. Objectives We aimed to compare the effects of 3 high-fiber isocaloric diets differing in %kcal of carbohydrate, protein, or unsaturated fat on circulating SCFAs. Based on previous literature, we hypothesized that serum acetate, the main SCFA in circulation, increases on all high-fiber diets, but differently by macronutrient composition of the diet. Methods OmniHeart is a randomized crossover trial of 164 men and women (≥30 y old); 163 participants with SCFA data were included in this analysis. We provided participants 3 isocaloric high-fiber (∼30 g/2100 kcal) diets, each for 6 wk, in random order: a carbohydrate-rich (Carb) diet, a protein-rich (Prot) diet (protein predominantly from plant sources), and an unsaturated fat–rich (Unsat) diet. We used LC-MS to quantify SCFA concentrations in fasting serum, collected at baseline and the end of each diet period. We fitted linear regression models with generalized estimating equations to examine change in ln-transformed SCFAs from baseline to the end of each diet; differences between diets; and associations of changes in SCFAs with cardiometabolic parameters. Results From baseline, serum acetate concentrations were increased by the Prot (β: 0.24; 95% CI: 0.12, 0.35), Unsat (β: 0.21; 95% CI: 0.10, 0.33), and Carb (β: 0.12; 95% CI: 0.01, 0.24) diets; between diets, only Prot compared with Carb was significant (P  = 0.02). Propionate was decreased by the Carb (β: −0.10; 95% CI: −0.16, −0.03) and Unsat (β: −0.10; 95% CI: −0.16, −0.04) diets, not the Prot diet; between diet comparisons of Carb vs. Prot (P  = 0.006) and Unsat vs. Prot (P  = 0.002) were significant. The Prot diet increased butyrate (β: 0.05; 95% CI: 0.00, 0.09) compared with baseline, but not compared with the other diets. Increases in acetate were associated with decreases in insulin and glucose; increases in propionate with increases in leptin, LDL cholesterol, and blood pressure; and increases in butyrate with increases in insulin and glucose, and decreases in HDL cholesterol and ghrelin (P s < 0.05). Conclusions Macronutrient composition of high-fiber diets affects circulating SCFAs, which are associated with measures of appetite and cardiometabolic health. This trial was registered at clinicaltrials.gov as NCT00051350. [ABSTRACT FROM AUTHOR]

Background Alaska Native (AN) people have the world's highest recorded incidence of sporadic colorectal cancer (CRC) (∼91:100,000), whereas rural African (RA) people have the lowest risk (<5:100,000). Previous data supported the hypothesis that diet affected CRC risk through its effects on the colonic microbiota that produce tumor-suppressive or -promoting metabolites. Objectives We investigated whether differences in these metabolites may contribute to the high risk of CRC in AN people. Methods A cross-sectional observational study assessed dietary intake from 32 AN and 21 RA healthy middle-aged volunteers before screening colonoscopy. Analysis of fecal microbiota composition by 16S ribosomal RNA gene sequencing and fecal/urinary metabolites by 1H-NMR spectroscopy was complemented with targeted quantification of fecal SCFAs, bile acids, and functional microbial genes. Results Adenomatous polyps were detected in 16 of 32 AN participants, but not found in RA participants. The AN diet contained higher proportions of fat and animal protein and less fiber. AN fecal microbiota showed a compositional predominance of Blautia and Lachnoclostridium , higher microbial capacity for bile acid conversion, and low abundance of some species involved in saccharolytic fermentation (e.g., Prevotellaceae, Ruminococcaceae), but no significant lack of butyrogenic bacteria. Significantly lower concentrations of tumor-suppressive butyrate (22.5 ± 3.1 compared with 47.2 ± 7.3 SEM µmol/g) coincided with significantly higher concentrations of tumor-promoting deoxycholic acid (26.7 ± 4.2 compared with 11 ± 1.9 µmol/g) in AN fecal samples. AN participants had lower quantities of fecal/urinary metabolites than RA participants and metabolite profiles correlated with the abundance of distinct microbial genera in feces. The main microbial and metabolic CRC-associated markers were not significantly altered in AN participants with adenomatous polyps. Conclusions The low-fiber, high-fat diet of AN people and exposure to carcinogens derived from diet or environment are associated with a tumor-promoting colonic milieu as reflected by the high rates of adenomatous polyps in AN participants. [ABSTRACT FROM AUTHOR]

Background Overall quality of dietary carbohydrate intake rather than total carbohydrate intake may determine the risk of cardiovascular disease (CVD). Objective We examined 6- and 12-mo changes in carbohydrate quality index (CQI) and concurrent changes in several CVD risk factors in a multicenter, randomized, primary-prevention trial (PREDIMED-Plus) based on an intensive weight-loss lifestyle intervention program. Methods Prospective analysis of 5373 overweight/obese Spanish adults (aged 55–75 y) with metabolic syndrome (MetS). Dietary intake information obtained from a validated 143-item semiquantitative food-frequency questionnaire was used to calculate 6- and 12-mo changes in CQI (categorized in quintiles), based on 4 criteria (total dietary fiber intake, glycemic index, whole grain/total grain ratio, and solid carbohydrate/total carbohydrate ratio). The outcomes were changes in intermediate markers of CVD. Results During the 12-mo follow-up, the majority of participants improved their CQI by increasing their consumption of fruits, vegetables, legumes, fish, and nuts and decreasing their consumption of refined cereals, added sugars, and sugar-sweetened beverages. After 6 mo, body weight, waist circumference (WC), systolic and diastolic blood pressure (BP), fasting blood glucose, glycated hemoglobin (HbA1c), triglyceride levels, triglycerides and glucose (TyG) index, and TyG-WC decreased across successive quintiles of improvement in the CQI. After 12 mo, improvements were additionally observed for HDL cholesterol and for the ratio of total to HDL cholesterol. Favorable improvements (expressed in common units of SD and 95% CI) for quintile 5 compared with quintile 1 of CQI change were observed for most risk factors, including TyG-WC (SD −0.20; 95% CI −0.26, −0.15), HbA1c (SD −0.16; 95% CI −0.23, −0.10), weight (SD −0.12; 95% CI −0.14, −0.09), systolic BP (SD −0.11; 95% CI −0.19, −0.02) and diastolic BP (SD −0.11; 95% CI −0.19, −0.04). Conclusions Improvements in CQI were strongly associated with concurrent favorable CVD risk factor changes maintained over time in overweight/obese adults with MetS. This trial was registered as ISRCTN 89898870. [ABSTRACT FROM AUTHOR]

Background The role of dietary fiber in obesity management remains debatable. Evidence suggests that intake of viscous fiber may have the potential to facilitate weight loss. Objective We aimed to summarize and quantify the effects of viscous fiber on body weight, BMI, waist circumference, and body fat, independent of calorie restriction, through a systematic review and meta-analysis of randomized controlled trials. Methods Trials ≥4 wk in duration that assessed the effect of viscous fiber supplemented to an ad libitum diet along with comparator diets were included. MEDLINE, EMBASE, and the Cochrane library were searched through 24 July, 2019. Two independent reviewers extracted relevant data. Data were pooled using the generic inverse variance method and random-effects models and expressed as mean differences with 95% CIs. Interstudy heterogeneity was assessed (Cochran Q statistic) and quantified (I 2 statistic). The overall certainty of evidence was explored using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach. Results Findings from 62 trials (n  = 3877) showed that viscous fiber reduced mean body weight (−0.33 kg; 95% CI: −0.51, −0.14 kg; P  = 0.004), BMI (in kg/m2) (−0.28; 95% CI: −0.42, −0.14; P  = 0.0001), and waist circumference (−0.63 cm; 95% CI: −1.11, −0.16 cm; P  = 0.008), with no change in body fat (−0.78%; 95% CI: −1.56%, 0.00%; P  = 0.05) when consumed with an ad libitum diet. Greater reductions in body weight were observed in overweight individuals and those with diabetes and metabolic syndrome. The certainty of evidence was graded moderate for body weight, high for waist circumference and body fat, and low for BMI. Conclusions Dietary viscous fiber modestly yet significantly improved body weight and other parameters of adiposity independently of calorie restriction. Future trials are warranted to address the inconsistency and imprecision identified through GRADE and to determine long-term weight-loss sustainability. This systematic review and meta-analysis was registered at clinicaltrials.gov as NCT03257449. [ABSTRACT FROM AUTHOR]

Background Previous studies have shown mixed results on the association between carbohydrate intake and insomnia. However, any influence that refined carbohydrates have on risk of insomnia is likely commensurate with their relative contribution to the overall diet, so studies are needed that measure overall dietary glycemic index (GI), glycemic load, and intakes of specific types of carbohydrates. Objective We hypothesized that higher GI and glycemic load would be associated with greater odds of insomnia prevalence and incidence. Methods This was a prospective cohort study with postmenopausal women who participated in the Women's Health Initiative Observational Study, investigating the relations of GI, glycemic load, other carbohydrate measures (added sugars, starch, total carbohydrate), dietary fiber, and specific carbohydrate-containing foods (whole grains, nonwhole/refined grains, nonjuice fruits, vegetables, dairy products) with odds of insomnia at baseline (between 1994 and 1998; n  = 77,860) and after 3 y of follow-up (between 1997 and 2001; n  = 53,069). Results In cross-sectional and longitudinal analyses, higher dietary GI was associated with increasing odds of prevalent (fifth compared with first quintile OR: 1.11; CI: 1.05, 1.16; P -trend = 0.0014) and incident (fifth compared with first quintile OR: 1.16; CI: 1.08, 1.25; P -trend < 0.0001) insomnia in fully adjusted models. Higher intakes of dietary added sugars, starch, and nonwhole/refined grains were each associated with higher odds of incident insomnia. By contrast, higher nonjuice fruit and vegetable intakes were significantly associated with lower odds of incident insomnia. Also, higher intakes of dietary fiber, whole grains, nonjuice fruit, and vegetables were significantly associated with lower odds of prevalent insomnia. Conclusions The results suggest that high-GI diets could be a risk factor for insomnia in postmenopausal women. Substitution of high-GI foods with minimally processed, whole, fiber-rich carbohydrates should be evaluated as potential treatments of, and primary preventive measures for, insomnia in postmenopausal women. [ABSTRACT FROM AUTHOR]

Background Gut microbiota data obtained by DNA sequencing are complex and compositional because of large numbers of detectable taxa, and because microbiota characteristics are described in relative terms. Nutrition researchers use principal component analysis (PCA) to derive dietary patterns from food data. Although compositional PCA methods are not commonly used to describe patterns from complex microbiota data, this approach would be useful for identifying gut microbiota patterns associated with diet and body composition. Objectives To use compositional PCA to describe the principal components (PCs) of gut microbiota in 5-y-old children and explore associations between microbiota components, diet, and BMI z -score. Methods A fecal sample was provided by 319 children aged 5 y. Their primary caregiver completed a validated 123-item quantitative FFQ. Body composition was determined using DXA, and a BMI z -score was calculated. Compositional PCA identified characterizing taxa and weightings for calculation of gut microbiota PC scores at the genus level, and was examined in relation to diet and body size. Results Three gut microbiota PCs were found. PC1 (negative loadings on uncultured Christensenellaceae and Ruminococcaceae) was related to lower BMI z -scores and longer duration of breastfeeding (per month) (β = −0.14; 95% CI: −0.26, −0.02; and β = 0.02; 95% CI: 0.003, 0.34, respectively). PC2 (positive loadings on Fusicatenibacter and Bifidobacterium ; negative loadings on Bacteroides) was associated with a lower intake of nuts, seeds, and legumes (β = −0.05 per gram; 95% CI: −0.09, −0.01). When adjusted for fiber intake, PC2 was also associated with higher BMI z -scores (β = 0.12; 95% CI: 0.01, 0.24). PC3 (positive loadings on Faecalibacterium, Eubacterium , and Roseburia) was associated with higher intakes of fiber (β = 0.02 per gram; 95% CI: 0.003, 0.04) and total nonstarch polysaccharides (β = 0.02 per gram; 95% CI: 0.003, 0.04). Conclusions Our results suggest that specific gut microbiota components determined using compositional PCA are associated with diet and BMI z -score. This trial was registered at clinicaltrials.gov as NCT00892983. [ABSTRACT FROM AUTHOR]

Background Recently, a group of betainized compounds have been suggested to play a role in health effects in relation to a whole-grain-rich diet. Objectives The aims of this study were to develop a quantitative mass spectrometric method for selected betainized compounds in human plasma, and to investigate their association with nutrient intake and measures of metabolic health in participants of the SYSDIET study. Methods The SYSDIET study was a controlled randomized intervention including individuals with metabolic syndrome, where the healthy Nordic diet (HND) group increased intakes of whole grains, canola oil, berries, and fish, whereas the control diet (CD) group consumed low-fiber cereal products, milk fat, and restricted amounts of fish and berries. A quantitative LC combined with triple quadrupole MS method for betainized compounds was developed and applied to fasting plasma samples from baseline (week 0) and the end of the intervention (week 18 or 24). Concentrations of betainized compounds were correlated with intakes of selected nutrients and fiber and measures of metabolic health. Results Pipecolic acid betaine (PAB) concentrations were significantly higher in the HND group than in the CD group (P  = 0.00032) at the end of the intervention and correlated directly (P  < 0.0001) with intakes of dietary fiber (r  = 0.376) and a biomarker related to whole-grain rye intake, namely the ratio of alkylresorcinol C17:0 to C21:0 (r  = 0.442). PAB was associated inversely with fasting plasma insulin consistently at the beginning and at the end of the intervention (P  < 0.001, r  = −0.300; P  < 0.01, r  = −0.250, respectively), as well as IL-1 receptor antagonist (P  < 0.01, r  = −0.232 at the beginning; P  < 0.01, r  = −0.236 at the end) and serum LDL/HDL cholesterol (P  < 0.01, r  = −0.239 at the beginning; P  < 0.01, r  = −0.241 at the end). Conclusions Among adults with the metabolic syndrome, PAB plasma concentrations were associated with fasting insulin, inflammation, and lipids and were significantly increased with adoption of the HND. Further studies are needed to clarify the biological functions of betainized compounds. This trial was registered at clinicaltrials.gov as NCT00992641. [ABSTRACT FROM AUTHOR]

Background Inulin-type fructans (ITFs) are a type of fermentable dietary fiber that can confer beneficial health effects through changes in the gut microbiota. However, their effect on gut sensitivity and nutritional behavior is a matter of debate. Objective We evaluated the impact of consuming ITF-rich vegetables daily on gut microbiota, gastro-intestinal symptoms, and food-related behavior in healthy individuals. Methods A single group-design trial was conducted in 26 healthy individuals. During 2 wk, the participants were instructed to adhere to a controlled diet based on ITF-rich vegetables (providing a mean intake of 15 g ITF/d). Three test days were organized: before and after the nutritional intervention and 3 wk after returning to their usual diet. We assessed nutrient intake, food-related behavior, fecal microbiota composition, microbial fermentation, and gastrointestinal symptoms. Results The major microbial modifications during the intervention were an increased proportion of the Bifidobacterium genus, a decreased level of unclassified Clostridiales, and a tendency to decrease Oxalobacteraceae. These changes were reversed 3 wk after the intervention. The volunteers showed greater satiety, a reduced desire to eat sweet, salty, and fatty food, and a trend to increase hedonic attitudes towards some inulin-rich vegetables. Only flatulence episodes were reported during the dietary intervention, whereas intestinal discomfort, inversely associated with Clostridium cluster IV and Ruminococcus callidus, was improved at the end of the intervention. Conclusions A higher consumption of ITF-rich vegetables allows a substantial increase in well-tolerated dietary fiber, which may in turn improve food-related behavior. Moreover, it leads to beneficial modifications of the gut microbiota composition and function. This trial is registered at clinicaltrial.gov as NCT03540550. [ABSTRACT FROM AUTHOR]

Background Wholegrain consumption has been associated with beneficial health effects including reduction of diabetes and cancer risk; however, the underlying mechanisms are not fully understood. Objective The aim of this study was to characterize the effects of wholegrain rye intake on circulating metabolites in a human intervention study using untargeted metabolomics. Methods The intervention consisted of 2 successive 4-wk periods in a randomized crossover design, where 15 adults consumed wholegrain rye bread (WGR) or white wheat bread enriched with fermented rye bran (WW+RB), following a 4-wk rye-free period with white wheat bread (WW). Fasting plasma samples were collected at the end of each period and analyzed using liquid chromatography-mass spectrometry. Metabolic profiles were compared to identify compounds discriminating WGR from the WW+RB and WW periods. Because peripheral serotonin is produced mainly in the gut, a hypothesis of its altered biosynthesis as a response to increased cereal fiber intake was tested by measuring intestinal serotonin of mice fed for 9 wk on a high-fat diet supplemented with different sources of fiber (rye bran flour, ground wheat aleurone, or powdered cellulose). Results Five endogenous metabolites and 15 rye phytochemicals associated with WGR intake were identified. Plasma concentrations of serotonin, taurine, and glycerophosphocholine were significantly lower after the WGR than WW period (Q  < 0.05). Concentrations of 2 phosphatidylethanolamine plasmalogens, PE(18:2/P-18:0) and PE(18:2/P-16:0), were lower after the WGR period than the WW+RB period (Q  < 0.05). The concentration of serotonin was significantly lower in the colonic tissue of mice that consumed rye bran or wheat aleurone compared with cellulose (P  < 0.001). Conclusions Wholegrain rye intake decreases plasma serotonin in healthy adults when compared with refined wheat. Intake of rye bran and wheat aleurone decreases colonic serotonin in mice. These results suggest that peripheral serotonin could be a potential link between wholegrain consumption and its associated health effects. Data used in the study were derived from a trial registered at www.clinicaltrials.gov as NCT03550365. [ABSTRACT FROM AUTHOR]

Background: Epidemiological studies suggest that an increased red meat intake is associated with a higher risk of type 2 diabetes, whereas an increased fiber intake is associated with a lower risk. Objectives: We conducted an intervention study to investigate the effects of these nutritional factors on glucose and lipid metabolism, body-fat distribution, and liver fat content in subjects at increased risk of type 2 diabetes. Methods: This prospective, randomized, and controlled dietary intervention study was performed over 6 mo. All groups decreased their daily caloric intake by 400 kcal. The “control” group (N = 40) only had this requirement. The “no red meat” group (N = 48) in addition aimed to avoid the intake of red meat, and the “fiber” group (N = 44) increased intake of fibers to 40 g/d. Anthropometric parameters and frequently sampled oral glucose tolerance tests were performed before and after intervention. Body-fat mass and distribution, liver fat, and liver iron content were assessed by MRI and single voxel proton magnetic resonance spectroscopy. Results: Participants in all groups lost weight (mean 3.3 ± 0.5 kg, P < 0.0001). Glucose tolerance and insulin sensitivity improved (P < 0.001), and body and visceral fat mass decreased in all groups (P < 0.001). These changes did not differ between groups. Liver fat content decreased significantly (P < 0.001) with no differences between the groups. The decrease in liver fat correlated with the decrease in ferritin during intervention (r² = 0.08, P = 0.0021). This association was confirmed in an independent lifestyle intervention study (Tuebingen Lifestyle Intervention Program, N = 229, P = 0.0084). Conclusions: Our data indicate that caloric restriction leads to a marked improvement in glucose metabolism and body-fat composition, including liver-fat content. The marked reduction in liver fat might be mediated via changes in ferritin levels. In the context of caloric restriction, there seems to be no additional beneficial impact of reduced red meat intake and increased fiber intake on the improvement in cardiometabolic risk parameters. [ABSTRACT FROM AUTHOR]

The authors discuss a study that examined the association of dietary fiber intake with mortality outcomes in Japan. Highlights include the link between higher intakes of fiber from beans, fruits, and vegetables and lower risk of total mortality, types of fiber that have been shown to reduce the postprandial rise in blood glucose, and the effects of diets in an industrialized community.

Human gut microbiota has been suggested to play an important role in nutrition and obesity. However, formulating meaningful and clinically relevant dietary advice based on knowledge about gut microbiota remains a key challenge. A number of recent studies have found evidence that stratification of individuals according to 2 microbial enterotypes (dominance of either Prevotella or Bacteroides) may be useful in predicting responses to diets and drugs. Here, we review enterotypes in a nutritional context and discuss how enterotype stratification may be used in personalized nutrition in obesity management. Enterotypes are characterized by distinct digestive functions with preference for specific dietary substrate, resulting in short-chain fatty acids that may influence energy balance in the host. Consequently, the enterotype potentially affects the individual's ability to lose weight when following a specific diet. In short, a high-fiber diet seems to optimize weight loss among Prevotella-enterotype subjects but not among Bacteroides-enterotype subjects. In contrast, increasing bifidobacteria in the gut among Bacteroides-enterotype subjects improves metabolic parameters, suggesting that this approach can be used as an alternative weight loss strategy. Thus, enterotypes, as a pretreatment gut microbiota biomarker, have the potential to become an important tool in personalized nutrition and obesity management, although further interventions assessing their applicability are warranted. [ABSTRACT FROM AUTHOR]

Dietary fiber (DF) comprises a wide range of naturally occurring and modified materials with substantial variations in physical and chemical properties and potential physiologic effects. Although nutrition studies testing the effects of DF usually provide extensive detail on the physiologic responses,many still fail to adequately report the type and properties of the DF itself. This weakens the ability to directly replicate and compare studies and to establish structure-function relations. We outline the factors that affect DF functionality and provide 4 overarching recommendations for the characterization and reporting ofDF preparations andDF-containing foods in nutrition research. These relate to 1) undertaking characterization methods that reflect the study hypothesis; 2) adequate reporting of DF source, quantity, and composition; 3) measurement of DF rheological properties; and 4) estimation of the DF fermentation rate and extent. Importantly, the food matrix of the test products should also be considered, because this can influence DF functionality and hence the apparent DF efficacy for health-relevant outcomes. Finally, we point out differences in DF functionality to be considered in acute and longer-term trials, the need to design the control treatment according to the research question, and the importance of reporting the amount and type of DF in the background diet. [ABSTRACT FROM AUTHOR]

Background: Dysfunction of the gut microbiota is frequently reported as a manifestation of chronic diseases, and therefore presents as a modifiable risk factor in their development. Diet is a major regulator of the gut microbiota, and certain types of dietary fiber may modify bacterial numbers and metabolism, including short-chain fatty acid (SCFA) generation. Objective: A systematic review and meta-analysis were undertaken to assess the effect of dietary fiber interventions on gut microbiota composition in healthy adults. Design: A systematic search was conducted acrossMEDLINE, EMBASE, CENTRAL, and CINAHL for randomized controlled trials using culture and/or molecular microbiological techniques evaluating the effect of fiber intervention on gut microbiota composition in healthy adults. Meta-analyses via a random-effects model were performed on alpha diversity, prespecified bacterial abundances including Bifidobacterium and Lactobacillus spp., and fecal SCFA concentrations comparing dietary fiber interventions with placebo/low-fiber comparators. Results: A total of 64 studies involving 2099 participants were included. Dietary fiber intervention resulted in higher abundance of Bifidobacterium spp. (standardized mean difference (SMD): 0.64; 95% CI: 0.42, 0.86; P < 0.00001) and Lactobacillus spp. (SMD: 0.22; 0.03, 0.41; P = 0.02) as well as fecal butyrate concentration (SMD: 0.24; 0.00, 0.47; P = 0.05) compared with placebo/low-fiber comparators. Subgroup analysis revealed that fructans and galactooligosaccharides led to significantly greater abundance of both Bifidobacterium spp. and Lactobacillus spp. compared with comparators (P < 0.00001 and P = 0.002, respectively). No differences in effect were found between fiber intervention and comparators for α-diversity, abundances of other prespecified bacteria, or other SCFA concentrations. Conclusions: Dietary fiber intervention, particularly involving fructans and galacto-oligosaccharides, leads to higher fecal abundance of Bifidobacterium and Lactobacillus spp. but does not affect α-diversity. Further research is required to better understand the role of individual fiber types on the growth of microbes and the overall gut microbial community. This review was registered at PROSPERO as CRD42016053101. [ABSTRACT FROM AUTHOR]

Background: Exposure to vegetable flavors during infancy and toddlerhood is hypothesized to enhance vegetable acceptance when children transition to table foods. Objective: We sought to examine the vegetable types, ingredients, and nutrient contents of vegetable-containing infant and toddler foods (ITFs) manufactured and sold in the United States. Design: A database of ITFs that contain vegetables (n = 548) was compiled from websites of companies based in the United States (n = 24). Product information was recorded, including intended age or stage, ingredient lists, and selected nutrients from the Nutrition Facts label. Ingredient lists were used to categorize vegetables using the USDA vegetable categories: dark green (e.g., spinach), red and orange (e.g., carrots), starchy (e.g., green peas, corn), beans and peas (e.g., black beans), and other (e.g., green beans, beets). Furthermore, products were categorized as single-vegetable, multi-vegetable, vegetable and fruit, vegetable and meat, or vegetable and other combinations (e.g., grains and and or dairy). Nutrients were examined, including energy (kilocalories), carbohydrates, fiber, and total sugars [per serving, per 100 g, per reference amount customarily consumed (RACC), and percentage of kilocalories from sugars]. Results: Of the 548 vegetable products, only 52 single-vegetable products (9.5%) were identified, none of which contained dark green vegetables or beans and peas. Red and orange vegetables most often appeared as the first ingredient (23.7%) compared to other vegetable types, such as dark green vegetables, which were rarely listed first (1.1%). Fruits were listed as the first ingredient more commonly than all vegetables (37.8%). One-way ANOVA revealed that vegetable and fruit products contained more sugars on average than did vegetable products with other ingredients, such as dairy and/or grains (all P values < 0.001). Conclusions: Current available products do not provide caregivers with a sufficient variety of single-vegetable products or products containing dark green vegetables to facilitate children's subsequent acceptance of these vegetables. Guidance should include making caregivers aware of the limitations of commercial ITFs manufactured and sold in the US market. [ABSTRACT FROM AUTHOR]

Background: Several studies have suggested that higher consumption of dietary fiber is beneficial for a variety of health outcomes. However, many results have been inconclusive and, to our knowledge, there has been no attempt to systematically capture the breadth of outcomes associated with dietary fiber intake or to systematically assess the quality and the strength of the evidence on the associations of dietary fiber intake and different health outcomes or medical conditions. Objective: The aim of this study was to describe the diverse health outcomes convincingly associated with dietary fiber consumption. Design: This was an umbrella review of systematic reviews with meta-analysis of observational studies. For each association, random-effects summary effect size, 95% CIs, and 95% prediction intervals were estimated. We also assessed heterogeneity, evidence for small-study effect, and evidence for excess significance bias. We used these metrics to evaluate the credibility of the identified evidence. Results: Our literature search identified 1351 abstracts. Of these, 18 meta-analyses including a total of 298 prospective observational studies and 21 outcomes were included. Outcomes studied included cancer and precancer lesions (n = 12), cardiovascular diseases (CVDs; n = 3), all-cause and specific-cause mortality (n = 4), type 2 diabetes (n = 1), and Crohn disease (n = 1). Overall, 6 (29%) of the 21 eligible outcomes reported highly significant summary results (P < 1 x 10-6); these included CVD and CVD mortality, coronary artery disease, pancreatic cancer, and gastric cancer. Overall, 3 of 21 (14%) outcomes presented convincing evidence (pancreatic cancer, CVD mortality, and all-cause mortality), but only CVD and all-cause mortality were based on prospective studies. Two other outcomes (10%), CVD and coronary artery disease, presented highly suggestive evidence based on prospective studies. Conclusion: Our results support dietary recommendations that promote higher fiber intake as part of a healthy diet. [ABSTRACT FROM AUTHOR]

Background: Meat and dietary fiber are associated with increased and decreased risk of colorectal cancer (CRC), respectively. Toll-like receptors (TLRs) regulate the intestinal immune response in a complex interplay between the mucosal epithelium and the microbiota and may therefore be important modulators of diet-induced CRC together with other inflammatory mediators. Objective: Our aim was to investigate the association between functional TLR polymorphisms and risk of CRC and the interaction with dietary factors. Additionally, interactions with previously studied polymorphisms in IL10, IL1B, PTGS2, and NFKB1 were assessed in order to examine possible biological pathways in meat-induced CRC. Design: A nested case-cohort study of 897 CRC cases and 1689 randomly selected participants from the Danish prospective "Diet, Cancer and Health" study encompassing 57,053 persons was performed using Cox proportional hazard models and the likelihood ratio test. Results: We found associations between polymorphisms in TLR2 (P = 0.018) and TLR4 (P = 0.044) and risk of CRC per se, interactions between intake of red and processed meat (10 g/d) and polymorphisms in TLR1 (P-interaction = 0.032) and TLR10 (P-interaction = 0.026 and 0.036), and intake of cereals (50 g/d) and TLR4 (P-interaction = 0.044) in relation to risk of CRC. Intake of red and processed meat also interacted with combinations of polymorphisms in TLR1 and TLR10 and polymorphisms in NFKB1, IL10, IL1B, and PTGS2 (P-interaction; TLR1/rs4833095 x PTGS2/rs20417 = 0.021, TLR10/rs11096955 x IL10/rs3024505 = 0.047, TLR10/rs11096955 x PTGS2/rs20417 = 0.017, TLR10/rs4129009 x NFKB1/rs28362491 = 0.027, TLR10/rs4129009 x IL1B/rs4848306 = 0.020, TLR10/rs4129009 x IL1B/rs1143623 = 0.021, TLR10/rs4129009 x PTGS2/rs20417 = 0.027), whereas intake of dietary fiber (10 g/d) interacted with combinations of polymorphisms in TLR4, IL10, and PTGS2 (P-interaction; TLR4/rs1554973 x IL10/rs3024505 = 0.0012, TLR4/rs1554973 x PTGS2/rs20417 = 0.0041, TLR4/rs1554973 x PTGS2/rs5275 = 0.0064). Conclusions: Our study suggests that meat intake may activate TLRs at the epithelial surface, leading to CRC via inflammation by nuclear transcription factor-κB-initiated transcription of inflammatory genes, whereas intake of fiber may protect against CRC via TLR4-mediated secretion of interleukin-10 and cyclooxygenase-2. Our results should be replicated in other prospective cohorts with well-characterized participants. The trial was registered at www.clinicaltrials.gov as NCT03250637. [ABSTRACT FROM AUTHOR]

Background: The carbohydrate-to-fiber ratio is a recommended measure of carbohydrate quality; however, its relation to incident coronary heart disease (CHD) is not currently known. Objective:We aimed to assess the relation between various measures of carbohydrate quality and incident CHD. Design: Data on diet and lifestyle behaviors were prospectively collected on 75,020 women and 42,865 men participating in the Nurses' Health Study (NHS) and the Health Professionals Follow- Up Study (HPFS) starting in 1984 and 1986, respectively, and every 2-4 y thereafter until 2012. All participants were free of known diabetes mellitus, cancer, or cardiovascular disease at baseline. Cox proportional hazards regression models were used to assess the relation between dietary measures of carbohydrate quality and incident CHD. Results: After 1,905,047 (NHS) and 921,975 (HPFS) person-years of follow-up, we identified 7,320 cases of incident CHD. In models adjusted for age, lifestyle behaviors, and dietary variables, the highest quintile of carbohydrate intake was not associated with incident CHD (pooled-RR = 1.04; 95% CI: 0.96, 1.14; P-trend = 0.31). Total fiber intake was not associated with risk of CHD (pooled-RR = 0.94; 95% CI: 0.85, 1.03; P-trend = 0.72), while cereal fiber was associated with a lower risk for incident CHD (pooled-RR = 0.80; 95% CI: 0.74, 0.87; P-trend < 0.0001). In fully adjusted models, the carbohydrate-to-total fiber ratio was not associated with incident CHD (pooled-RR = 1.04; 95% CI: 0.96, 1.13; P-trend = 0.46). However, the carbohydrate-to-cereal fiber ratio and the starch-to-cereal fiber ratio were associated with an increased risk for incident CHD (pooled-RR = 1.20; 95% CI: 1.11, 1.29; P-trend < 0.0001, and pooled-RR = 1.17; 95%CI: 1.09, 1.27; P-trend < 0.0001, respectively). Conclusion: Dietary cereal fiber appears to be an important component of carbohydrate quality. The carbohydrate-to-cereal fiber ratio and the starch-to-cereal fiber ratio, but not the carbohydrate-tofiber ratio, was associated with an increased risk for incident CHD. Future research should focus on how various measures of carbohydrate quality are associated with CHD prevention. [ABSTRACT FROM AUTHOR]

Background: There is strong epidemiologic evidence that dietary fiber intake is protective against overweight and obesity; however, results of intervention studies have been mixed. Soluble fiber beneficially affects metabolism, and fiber supplementation may be a feasible approach to improve body composition and glycemia in adults with overweight and obesity. Objective: We evaluated randomized controlled trials (RCTs) of isolated soluble fiber supplementation in overweight and obese adults on outcomes related to weight management [body mass index (BMI; in kg/m²), body weight, percentage of body fat, and waist circumference] and glucose and insulin metabolism (homeostasis model assessment of insulin resistance and fasting insulin) through a systematic review and meta-analysis. Design: We searched PubMed, Web of Science, Cumulative Index to Nursing and Allied Health Literature and Cochrane Library databases. Eligible studies were RCTs that compared isolated soluble fiber with placebo treatments without energy-restriction protocols. Randomeffects models were used to estimate pooled effect sizes and 95% CIs. Meta-regressions were performed to assess outcomes in relation to the intervention duration, fiber dose, and fiber type. Publication bias was assessed via Begg's and Egger's tests and funnel plot inspection. Results: Findings from 12 RCTs (n = 609 participants) from 2 to 17 wk of duration are summarized in this review. Soluble fiber supplementation reduced BMI by 0.84 (95% CI: -1.35, -0.32; P = 0.001), body weight by 2.52 kg (95% CI: -4.25, -0.79 kg; P = 0.004), body fat by 0.41% (95% CI:-0.58%,-0.24%; P, 0.001), fasting glucose by 0.17 mmol/L (95% CI: -0.28, -0.06 mmol/L; P = 0.002), and fasting insulin by 15.88 pmol/L (95% CI: 229.05, -2.71 pmol/L; P = 0.02) compared with the effects of placebo treatments. No publication bias was identified. Considerable between-study heterogeneity was observed for most outcomes. Conclusions: Isolated soluble fiber supplementation improves anthropometric and metabolic outcomes in overweight and obese adults, thereby indicating that supplementation may improve fiber intake and health in these individuals. However, the interpretation of these findings warrants caution because of the considerable between-study heterogeneity. [ABSTRACT FROM AUTHOR]