Whole grain intake, diet quality and risk factors of chronic diseases: results from a population-based study in Finnish adults.

OBJECTIVES: Better diet quality of whole grain consumers could contribute to the associations between whole grain intake and chronic disease risk factors. We examined whole grain intake in relation to diet quality and chronic disease risk factors (anthropometrics, blood pressure, cholesterol, triglycerides, C-reactive protein and glucose) and the role of diet quality in whole grains' associations with each risk factor. METHODS: Our data included 5094 Finnish adults who completed a validated food frequency questionnaire and participated in a health examination within the National FinHealth 2017 Study. We assessed diet quality by the modified Baltic Sea Diet Score. P trends were calculated across whole grain intake quintiles by linear regression analysis. Interactions were assessed by including an interaction term in the analyses. RESULTS: Higher whole grain intake was associated with slightly better diet quality compared with lower intakes in both sexes (P < 0.001). Whole grain intake was inversely associated with body mass index (P < 0.001), waist circumference (P < 0.001) and total cholesterol (P = 0.02) in men. Adjusting for medication use attenuated the inverse associations with diastolic blood pressure (P = 0.06) and HDL cholesterol (P = 0.14) in men. We observed no associations in women. Diet quality did not modify the associations between whole grain intake and chronic disease risk factors. CONCLUSIONS: Our results suggest that whole grain intake was associated with small improvements in the chronic disease risk factors in men, regardless of diet quality. The sex differences may arise from varying health associations of whole grains from different cereal sources.

Dietary strategies for gut-derived protein-bound uremic toxins and cardio-metabolic risk factors in chronic kidney disease: A focus on dietary fibers.

Chronic kidney disease (CKD) is associated with altered composition and function of gut microbiota. The cause of gut dysbiosis in CKD is multifactorial and encompasses the following: uremic state, metabolic acidosis, slow colonic transit, dietary restrictions of plant-based fiber-rich foods, and pharmacological therapies. Dietary restriction of potassium-rich fruits and vegetables, which are common sources of fermentable dietary fibers, inhibits the conversion of dietary fibers to short-chain fatty acids (SCFA), which are the primary nutrient source for the symbiotic gut microbiota. Reduced consumption of fermentable dietary fibers limits the population of SCFA-forming bacteria and causes dysbiosis of gut microbiota. Gut dysbiosis induces colonic fermentation of protein and formation of gut-derived uremic toxins. In this review, we discuss the roles and benefits of dietary fiber on gut-derived protein-bound uremic toxins and plant-based dietary patterns that could be recommended to decrease uremic toxin formation in CKD patients. Recent studies have indicated that dietary fiber supplementation may be useful to decrease gut-derived uremic toxin formation and slow CKD progression. However, research on associations between adherence of healthy dietary patterns and gut-derived uremic toxins formation in patients with CKD is lacking.

[Prospects of dietary fibers food fortification for the treatment and prevention of gastrointestinal diseases: A review].

Epidemiological studies have proven the connection between high consumption of dietary fiber and a reduction in the risk of many diseases. In clinical trials, the possibility of functional regulation of the intestine and intestinal microbiome by dietary fibers has been revealed, which may be significant in certain diseases of the digestive system. This review provides information on the relationship between the physico-chemical properties and functional characteristics of dietary fibers, discusses evidence of the effectiveness of their use in the treatment of diseases of the digestive system, discusses the need to enrich food with dietary fibers.

The prebiotic effects of soluble dietary fiber mixture on renal anemia and the gut microbiota in end-stage renal disease patients on maintenance hemodialysis: a prospective, randomized, placebo-controlled study.

BACKGROUND: Renal anemia is caused by end-stage renal disease (ESRD) but has a complex etiology. The application of dietary fiber (DF) to regulate the gut microbiota has shown effective therapeutic effects in some diseases, but its role in renal anemia is not clear. The aim of this study was to explore the effect of DF on renal anemia by regulating the gut microbiota and its metabolite, short-chain fatty acids (SCFAs). METHODS: A total of 162 ESRD patients were enrolled and randomly distributed into a DF or a control group (received oral DF or potato starch, 10 g/day for 8 weeks). Hemoglobin (Hb), serum iron (Fe2+), serum ferritin (SF), soluble transferrin receptor (sTfR), hepcidin and the dosage of recombinant human erythropoietin (rhEPO) before and after intervention in patients were analyzed. The gut microbiota and SCFAs in both groups were analyzed by 16S rDNA sequencing and gas chromatography-mass spectrometry, respectively. Spearman's correlation test was used to analyze the correlation between the gut microbiota, SCFAs and the hematological indicators. RESULTS: Compared with the control group, (1) the patients in the DF group had higher Hb [117.0 (12.5) g/L vs. 94.0 (14.5) g/L, p < 0.001], Fe2+ [13.23 (4.83) µmol/L vs. 10.26 (5.55) µmol/L, p < 0.001], and SF levels [54.15 (86.66) ng/ml vs. 41.48 (36.60) ng/ml, p = 0.003]. (2) The rhEPO dosage in the DF group was not significantly decreased (p = 0.12). (3) Bifidobacterium adolescentis, Lactobacillus and Lactobacillaceae were increased in the DF group, and Lactobacillus and Lactobacillaceae were positively correlated with Hb (r = 0.44, p < 0.001; r = 0.44, p < 0.001) and Fe2+ levels (r = 0.26, p = 0.016; r = 0.26, p = 0.016) and negatively correlated with rhEPO dosage (r = - 0.45, p < 0.001; r = - 0.45, p < 0.001). (4) Patients in the DF group had elevated serum butyric acid (BA) levels [0.80 (1.65) vs. 0.05 (0.04), p < 0.001] and BA levels were positively correlated with Hb (r = 0.26, p = 0.019) and Fe2+ (r = 0.31, p = 0.005) and negatively correlated with rhEPO dosage (r = - 0.36, p = 0.001). Lactobacillus and Lactobacillaceae were positively correlated with BA levels (r = 0.78, p < 0.001; r = 0.78, p < 0.001). CONCLUSION: DF may improve renal anemia in ESRD patients by regulating the gut microbiota and SCFAs. Trial registration This study was registered in the China Clinical Trial Registry ( www.chictr.org.cn ) on December 20, 2018 ( ChiCTR1800020232 ).

Should high-fiber diets be recommended for patients with inflammatory bowel disease?

PURPOSE OF REVIEW: Dietary fiber intake in IBD patients has oftentimes generated conflicting data and clinical recommendations. This review aims to unify apparently conflicting lines of evidence regarding dietary fiber intake in IBD patients by highlighting new information from natural history studies and prospective clinical trials. RECENT FINDINGS: IBD patients have lower dietary fiber intake than the general population as well as national guideline recommendations. Patients report short-term benefits from fiber avoidance. Low fiber and low FODMAP diets are associated with lower fecal microbiota abundance and essential nutrient intake. There is emerging evidence suggesting that IBD patients may be able to increase dietary fiber intake with short-term benefit and good tolerability, particularly when fiber is introduced during clinical remission. Current societal recommendations do not favor withholding dietary fiber during long-term IBD management. The long-term impact of increased dietary fiber on IBD clinical outcomes remains unanswered. SUMMARY: Dietary fiber intake is not necessarily contraindicated in IBD patients.

A prospective multicenter study of the efficacy of a fiber-supplemented dietary intervention in dogs with chronic large bowel diarrhea.

BACKGROUND: Chronic large bowel diarrhea is common in dogs and can have a significant impact on their overall health and well being. We evaluated the safety and efficacy of a therapeutic food with select dietary plant fibers known to contain antioxidant and polyphenol compounds on clinical signs in dogs with chronic diarrhea. METHODS: A prospective clinical study was conducted in 31 adult dogs currently experiencing chronic diarrhea from private veterinary practices in the United States. Enrolled dogs were switched to a complete and balanced dry therapeutic food containing whole grains and polyphenol-containing fiber sources for 56 days. Veterinarians evaluated changes from baseline in overall clinical signs, recurrence of clinical signs, and stool parameters at Days 2, 3, 4, 28, and 56. Dog owners evaluated stool consistency daily and nausea/vomiting, quality of life (QoL), and stooling behaviors at Days 1, 14, 28, and 56. Statistical analysis was performed using a mixed-effects model with Day as a fixed-effect. RESULTS: Assessments of overall clinical response and stool parameters indicated that diarrhea improved significantly within 1 day of initiating the therapeutic food. Veterinarians reported that 68% of dogs had complete resolution of their clinical signs by Day 56 and the remaining 32% experienced improvement (P < 0.05), with no cases of recurrence. Veterinarians also reported improvement in stool consistency (P < 0.001) and reductions of blood and mucus in stool (P < 0.001). Significant improvements in nausea/vomiting, stooling behaviors, and quality of life (QoL) were reported by dog owners after 28 days and were sustained through day 56 (P < 0.05). The therapeutic food was safe and well tolerated. CONCLUSIONS: In dogs with chronic large bowel diarrhea, the therapeutic food rapidly improved stool consistency, resolved clinical signs, and improved stooling behaviors and QoL. Therapeutic foods supplemented with fiber sources rich in antioxidant and anti-inflammatory compounds contribute to rapid resolution of chronic diarrhea without recurrence and may contribute to long term health.

Microbiome function underpins the efficacy of a fiber-supplemented dietary intervention in dogs with chronic large bowel diarrhea.

BACKGROUND: Chronic large bowel diarrhea is a common occurrence in pet dogs. While nutritional intervention is considered the primary therapy, the metabolic and gut microfloral effects of fiber and polyphenol-enriched therapeutic foods are poorly understood. METHODS: This prospective clinical study enrolled 31 adult dogs from private veterinary practices with chronic, active large bowel diarrhea. Enrolled dogs received a complete and balanced dry therapeutic food containing a proprietary fiber bundle for 56 days. Metagenomic and metabolomic profiling were performed on fecal samples at Days 1, 2, 3, 14, 28, and 56; metabolomic analysis was conducted on serum samples taken at Days 1, 2, 3, 28, and 56. RESULTS: The dietary intervention improved clinical signs and had a clear effect on the gut microfloral metabolic output of canines with chronic diarrhea, shifting gut metabolism from a predominantly proteolytic to saccharolytic fermentative state. Microbial metabolism of tryptophan to beneficial indole postbiotics and the conversion of plant-derived phenolics into bioavailable postbiotics were observed. The intervention altered the endocannabinoid, polyunsaturated fatty acid, and sphingolipid profiles, suggesting a modulation in gastrointestinal inflammation. Changes in membrane phospholipid and collagen signatures were indicative of improved gut function and possible alleviation of the pathophysiology related to chronic diarrhea. CONCLUSIONS: In dogs with chronic diarrhea, feeding specific dietary fibers increased gut saccharolysis and bioavailable phenolic and indole-related compounds, while suppressing putrefaction. These changes were associated with improved markers of gut inflammation and stool quality.

Research Progress on Hypoglycemic Mechanisms of Resistant Starch: A Review.

In recent years, the prevalence of diabetes is on the rise, globally. Resistant starch (RS) has been known as a kind of promising dietary fiber for the prevention or treatment of diabetes. Therefore, it has become a hot topic to explore the hypoglycemic mechanisms of RS. In this review, the mechanisms have been summarized, according to the relevant studies in the recent 15 years. In general, the blood glucose could be regulated by RS by regulating the intestinal microbiota disorder, resisting digestion, reducing inflammation, regulating the hypoglycemic related enzymes and some other mechanisms. Although the exact mechanisms of the beneficial effects of RS have not been fully verified, it is indicated that RS can be used as a daily dietary intervention to reduce the risk of diabetes in different ways. In addition, further research on hypoglycemic mechanisms of RS impacted by the RS categories, the different experimental animals and various dietary habits of human subjects, have also been discussed in this review.

[Efficacy of newly developed kombucha-based specialized food product for treatment of constipation-predominant irritable bowel syndrome].

According to studies, the prevalence of constipation in the population can reach 27% due to the low intake of dietary fiber. Increasing dietary fiber intake can improve bowel movements. The aim of the study was to assess the efficacy of a non-alcoholic fermented pasteurized kombucha drink enriched with inulin and vitamins in patients with constipation-predominant irritable bowel syndrome (IBS). Material and methods. The study (NCT05164861) was approved by Local Ethics Committee and enrolled subjects with IBS (according to ROME IV). The subjects were randomized to receive either 220 ml of a non-alcoholic drink, based on pasteurized kombucha (KG), enriched with inulin (1.15 g/100 ml) or 220 ml water (control group, CG), for 10 days. Standard examination included evaluation of stool frequency (bowel movements per day), stool form (with the Bristol stool scale) and evaluation of concomitant symptoms (abdominal pain/discomfort, abdominal fullness, bloating, and feeling of incomplete bowel emptying) with the use of 5-point Likert scale before (BL) and 10 days after the start of intervention (EOT). Using visual analog scales (VAS), the palatability of the studied food was assessed at the beginning and end of the observation period. Results. Significant increase of stool frequency was found at the EOT compared to BL in KG (n=20), Mean±SD: 0.60±0.31 to 0.85±0.19 times/day; p=0.004, while there was no change in CG (n=20): 0.63±0.33 vs 0.72±0.28, p=0.6. Mean values of stool scale form increased in KG (3.0±1.2 to 4.4±1.0, p=0.001), while remained unchanged in CG (2.9±1.2 vs 3.4±1.2, p=0.6). Mean values of the Bristol stool scale in KG and CG differed significantly at EOT (p=0.018). Significant decrease in mean values of incomplete bowel emptying feeling was found in KG (1.88±0.78 at BL vs 1.41±0.56 points at EOT, p=0.015), but not in the control group. There were no statistically significant differences between patient's reports of the studied groups for other symptoms (bitterness and dryness in the mouth, heartburn, nausea, abdominal pain and heaviness in the stomach after eating). Conclusion. The effectiveness of a pasteurized fermented non-alcoholic drink based on kombucha enriched with inulin has been proven by reducing the intensity of complaints significant for constipation, normalizing the frequency and consistency of stools.

Dietary fibres and IBS: translating functional characteristics to clinical value in the era of personalised medicine.

Clinical guidelines in the use of fibre supplementation for patients with IBS provide one-size-fits-all advice, which has limited value. This narrative review addresses data and concepts around the functional characteristics of fibre and subsequent physiological responses induced in patients with IBS with a view to exploring the application of such knowledge to the precision use of fibre supplements. The key findings are that first, individual fibres elicit highly distinct physiological responses that are associated with their functional characteristics rather than solubility. Second, the current evidence has focused on the use of fibres as a monotherapy for IBS symptoms overall without attempting to exploit these functional characteristics to elicit specific, symptom-targeted effects, or to use fibre types as adjunctive therapies. Personalisation of fibre therapies can therefore target several therapeutic goals. Proposed goals include achieving normalisation of bowel habit, modulation of gut microbiota function towards health and correction of microbial effects of other dietary therapies. To put into perspective, bulking fibres that are minimally fermented can offer utility in modulating indices of bowel habit; slowly fermented fibres may enhance the activities of the gut microbiota; and the combination of both fibres may potentially offer both benefits while optimising the activities of the microbiota throughout the different regions of the colon. In conclusion, understanding the GI responses to specific fibres, particularly in relation to the physiology of the individual, will be the future for personalising fibre therapy for enhancing the personalised management of patients with IBS.

What is the Evidence for Over the Counter Laxatives to Treat Childhood Constipation?

PURPOSE OF REVIEW: Functional constipation is a common pediatric GI disorder that is responsible for a significant portion of pediatric office visits each year. It presents a significant stressor for patients, their families, and providers alike. There are a variety of over the counter agents available for treatment of pediatric constipation. RECENT FINDINGS: Osmotic laxatives, such as polyethylene glycol 3350 (PEG 3350) and lactulose, remain the most effective and safe therapy for both long and short term treatment of pediatric functional constipation. Stimulant laxatives, like Senna and Bisacodyl, probiotics, fiber preparations, enemas, and suppositories make excellent choices for adjunct therapies in specific clinical scenarios. There are multiple over the counter pharmacologic agents with various mechanisms of action that have demonstrated efficacy in pediatric functional constipation. These therapies are generally safe and well tolerated by patients.

Microbiome Links Cigarette Smoke-Induced Chronic Obstructive Pulmonary Disease and Dietary Fiber via the Gut-Lung Axis: A Narrative Review.

Existing comprehensive management strategies for COPD effectively relieve the symptoms of patients, delay the deterioration of lung function, and prevent the progression of COPD through various means and multidisciplinary interventions. However, there has been limited progress in therapies that address the underlying causes of COPD pathogenesis. Recent studies have identified specific changes in the gut and pulmonary microbiota in response to exposure to smoke that can cause or exacerbate CS-COPD by regulating the inflammatory immune response in the lungs through the gut-lung axis. As a convenient and controllable intervention, modifying the diet to include more dietary fiber can effectively improve the prognosis of CS-COPD. Gut microbiota ferment dietary fiber to produce short-chain fatty acids, which connect the microbial communities in the lung and gut mucosa across the gut-lung axis, playing an anti-inflammatory and immunosuppressive role in the lungs. Given that the effect of dietary fiber on gut microbiota was highly similar to that of quitting smoking on gut microbiota, we assume that microbiota might be a potential therapeutic target for dietary fiber to alleviate and prevent CS-COPD. This study examines the similarities between pulmonary and gut microbiota changes in the presence of smoking and dietary fiber. It also highlights the mechanism by which SCFAs link pulmonary and gut microbiota in CS-COPD and analyzes the anti-inflammatory and immunomodulatory effects of short-chain fatty acids on CS-COPD via the gut-lung axis.

Diagnosis and Treatment of Irritable Bowel Syndrome: A Review.

IMPORTANCE: The prevalence of irritable bowel syndrome (IBS) in the United States is between 7% and 16%, most common in women and young people, with annual direct costs estimated at more than $1 billion dollars in the United States. Traditionally, the diagnosis of IBS has been based on the positive identification of symptoms that correlate with several different syndromes associated with disorders such as IBS diarrhea, IBS constipation, functional diarrhea, functional constipation, chronic functional abdominal pain, or bloating. Several peripheral and central mechanisms initiate gastrointestinal motor and sensory dysfunctions leading to IBS symptoms. Those dysfunctions may require evaluation in patients whose symptoms do not respond to first-line treatments. OBSERVATIONS: Validation studies of consensus symptom-based criteria have identified deficiencies that favor a simpler identification of the predominant symptoms of abdominal pain, bowel dysfunction, and bloating and exclusion of alarm symptoms such as unintentional weight loss, rectal bleeding, or recent change in bowel function. Symptom-based diagnosis of IBS is enhanced with additional history for symptoms of somatoform and psychological disorders and alarm symptoms, physical examination including digital rectal examination, and screening tests to exclude organic disease (by measuring hemoglobin and C-reactive protein concentrations). The initial treatment plan should include patient education, reassurance, and first-line treatments such as fiber and osmotic laxatives for constipation, opioids for diarrhea, antispasmodics for pain and for management of associated psychological disorders. For patients who do not respond to those IBS treatments, testing for specific functional disorders may be required in a minority of patients with IBS. These disorders include rectal evacuation disorder, abnormal colonic transit, and bile acid diarrhea. Their identification is followed by individualized treatment, such as pelvic floor retraining for rectal evacuation disorders, sequestrants for bile acid diarrhea, and secretory agents for constipation, although there is only limited evidence that this individualized management approach is effective. CONCLUSIONS AND RELEVANCE: Advances in the identification of specific dysfunctions as causes of individual symptoms in the "IBS spectrum" leads to the potential to enhance the diagnosis and management of symptoms for the majority of patients for whom first-line therapies of IBS and management of comorbid psychological disorders are insufficient.

Antioxidant and Anti-Inflammatory Potential of Polyphenols Contained in Mediterranean Diet in Obesity: Molecular Mechanisms.

Nutrition transition can be defined as shifts in food habits, and it is characterized by high-fat (chiefly saturated animal fat), hypercaloric and salty food consumption at the expense of dietary fibers, minerals and vitamins. Western dietary patterns serve as a model for studying the impact of nutrition transition on civilization diseases, such as obesity, which is commonly associated with oxidative stress and inflammation. In fact, reactive oxygen species (ROS) overproduction can be associated with nuclear factor-κB (NF-κB)-mediated inflammation in obesity. NF-κB regulates gene expression of several oxidant-responsive adipokines including tumor necrosis factor-α (TNF-α). Moreover, AMP-activated protein kinase (AMPK), which plays a pivotal role in energy homeostasis and in modulation of metabolic inflammation, can be downregulated by IκB kinase (IKK)-dependent TNF-α activation. On the other hand, adherence to a Mediterranean-style diet is highly encouraged because of its healthy dietary pattern, which includes antioxidant nutraceuticals such as polyphenols. Indeed, hydroxycinnamic derivatives, quercetin, resveratrol, oleuropein and hydroxytyrosol, which are well known for their antioxidant and anti-inflammatory activities, exert anti-obesity proprieties. In this review, we highlight the impact of the most common polyphenols from Mediterranean foods on molecular mechanisms that mediate obesity-related oxidative stress and inflammation. Hence, we discuss the effects of these polyphenols on a number of signaling pathways. We note that Mediterranean diet (MedDiet) dietary polyphenols can de-regulate nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) and NF-κB-mediated oxidative stress, and metabolic inflammation. MedDiet polyphenols are also effective in upregulating downstream effectors of several proteins, chiefly AMPK.

Opuntia ficus-indica (L.) Mill.: A Multi-Benefit Potential to Be Exploited.

Consumer interest in foods with enhanced nutritional quality has increased in recent years. The nutritional and bioactive characterization of fruits and their byproducts, as well as their use in the formulation of new food products, is advisable, contributing to decrease the global concerns related to food waste and food security. Moreover, the compounds present in these raw materials and the study of their biological properties can promote health and help to prevent some chronic diseases. Opuntia ficus-indica (L.) Mill. (prickly pear) is a plant that grows wild in the arid and semi-arid regions of the world, being a food source for ones and a potential for others, but not properly valued. This paper carries out an exhaustive review of the scientific literature on the nutritional composition and bioactive compounds of prickly pear and its constituents, as well as its main biological activities and applications. It is a good source of dietary fiber, vitamins and bioactive compounds. Many of its natural compounds have interesting biological activities such as anti-inflammatory, hypoglycemic and antimicrobial. The antioxidant power of prickly pear makes it a good candidate as an ingredient of new food products with fascinating properties for health promotion and/or to be used as natural extracts for food, pharmaceutic or cosmetic applications. In addition, it could be a key player in food security in many arid and semi-arid regions of the world, where there are often no more plants.

Fiber consumption and breast cancer incidence: A systematic review and meta-analysis of prospective studies.

BACKGROUND: Associations between fiber intake and breast cancer risk have been evaluated in prospective studies, but overall, the evidence is inconsistent. The authors performed a systematic review and meta-analysis of prospective studies to investigate the relation between intake of total and types of fiber with breast cancer incidence. METHODS: The MEDLINE and Excerpta Medica dataBASE (EMBASE) databases were searched through July 2019 for prospective studies that reported on the association between fiber consumption and incident breast cancer. The pooled relative risk (RR) and 95% confidence intervals (95% CI) were estimated comparing the highest versus the lowest category of total and types of fiber consumption, using a random-effects meta-analysis. RESULTS: The authors identified 17 cohort studies, 2 nested case-control studies, and 1 clinical trial study. Total fiber consumption was associated with an 8% lower risk of breast cancer (comparing the highest versus the lowest category, pooled RR, 0.92; 95% CI, 0.88-0.95 [I2  = 12.6%]). Soluble fiber was found to be significantly inversely associated with risk of breast cancer (pooled RR, 0.90 [95% CI, 0.84-0.96; I2 = 12.6%]) and insoluble fiber was found to be suggestively inversely associated with risk of breast cancer (pooled RR, 0.93 [95% CI, 0.86-1.00; I2 = 33.4%]). Higher total fiber intake was associated with a lower risk of both premenopausal and postmenopausal breast cancers (pooled RR, 0.82 [95% CI, 0.67-0.99; I2  = 35.2%] and pooled RR, 0.91 [95% CI, 0.88-0.95; I2  = 0.0%], respectively). Furthermore, the authors observed a nonsignificant inverse association between intake of total fiber and risk of both estrogen and progesterone receptor-positive and estrogen and progesterone receptor-negative breast cancers. CONCLUSIONS: A random-effects meta-analysis of prospective observational studies demonstrated that high total fiber consumption was associated with a reduced risk of breast cancer. This finding was consistent for soluble fiber as well as for women with premenopausal and postmenopausal breast cancer.

Carbohydrate quality and human health: a series of systematic reviews and meta-analyses.

BACKGROUND: Previous systematic reviews and meta-analyses explaining the relationship between carbohydrate quality and health have usually examined a single marker and a limited number of clinical outcomes. We aimed to more precisely quantify the predictive potential of several markers, to determine which markers are most useful, and to establish an evidence base for quantitative recommendations for intakes of dietary fibre. METHODS: We did a series of systematic reviews and meta-analyses of prospective studies published from database inception to April 30, 2017, and randomised controlled trials published from database inception to Feb 28, 2018, which reported on indicators of carbohydrate quality and non-communicable disease incidence, mortality, and risk factors. Studies were identified by searches in PubMed, Ovid MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials, and by hand searching of previous publications. We excluded prospective studies and trials reporting on participants with a chronic disease, and weight loss trials or trials involving supplements. Searches, data extraction, and bias assessment were duplicated independently. Robustness of pooled estimates from random-effects models was considered with sensitivity analyses, meta-regression, dose-response testing, and subgroup analyses. The GRADE approach was used to assess quality of evidence. FINDINGS: Just under 135 million person-years of data from 185 prospective studies and 58 clinical trials with 4635 adult participants were included in the analyses. Observational data suggest a 15-30% decrease in all-cause and cardiovascular related mortality, and incidence of coronary heart disease, stroke incidence and mortality, type 2 diabetes, and colorectal cancer when comparing the highest dietary fibre consumers with the lowest consumers Clinical trials show significantly lower bodyweight, systolic blood pressure, and total cholesterol when comparing higher with lower intakes of dietary fibre. Risk reduction associated with a range of critical outcomes was greatest when daily intake of dietary fibre was between 25 g and 29 g. Dose-response curves suggested that higher intakes of dietary fibre could confer even greater benefit to protect against cardiovascular diseases, type 2 diabetes, and colorectal and breast cancer. Similar findings for whole grain intake were observed. Smaller or no risk reductions were found with the observational data when comparing the effects of diets characterised by low rather than higher glycaemic index or load. The certainty of evidence for relationships between carbohydrate quality and critical outcomes was graded as moderate for dietary fibre, low to moderate for whole grains, and low to very low for dietary glycaemic index and glycaemic load. Data relating to other dietary exposures are scarce. INTERPRETATION: Findings from prospective studies and clinical trials associated with relatively high intakes of dietary fibre and whole grains were complementary, and striking dose-response evidence indicates that the relationships to several non-communicable diseases could be causal. Implementation of recommendations to increase dietary fibre intake and to replace refined grains with whole grains is expected to benefit human health. A major strength of the study was the ability to examine key indicators of carbohydrate quality in relation to a range of non-communicable disease outcomes from cohort studies and randomised trials in a single study. Our findings are limited to risk reduction in the population at large rather than those with chronic disease. FUNDING: Health Research Council of New Zealand, WHO, Riddet Centre of Research Excellence, Healthier Lives National Science Challenge, University of Otago, and the Otago Southland Diabetes Research Trust.

Chronic Constipation in the United States: Results From a Population-Based Survey Assessing Healthcare Seeking and Use of Pharmacotherapy.

OBJECTIVES: Chronic idiopathic constipation (CIC) is characterized by unsatisfactory defecation and difficult or infrequent stools. CIC affects 9%-20% of adults in the United States, and although prevalent, gaps in knowledge remain regarding CIC healthcare seeking and medication use in the community. We recruited a population-based sample to determine the prevalence and predictors of (i) individuals having discussed their constipation symptoms with a healthcare provider and (ii) the use of constipation therapies. METHODS: We recruited a representative sample of Americans aged 18 years or older who had experienced constipation. Those who met the Rome IV criteria for irritable bowel syndrome and opioid-induced constipation were excluded. The survey included questions on constipation severity, healthcare seeking, and the use of constipation medications. We used multivariable regression methods to adjust for confounders. RESULTS: Overall, 4,702 participants had experienced constipation (24.0% met the Rome IV CIC criteria). Among all respondents with previous constipation, 37.6% discussed their symptoms with a clinician (primary care provider 87.6%, gastroenterologist 26.0%, and urgent care/emergency room physician 7.7%). Age, sex, race/ethnicity, marital status, employment status, having a source of usual care, insurance status, comorbidities, locus of control, and constipation severity were associated with seeking care (P < 0.05). Overall, 47.8% of respondents were taking medication to manage their constipation: over-the-counter medication(s) only, 93.5%; prescription medication(s) only, 1.3%; and both over-the-counter medication(s) and prescription medication(s), 5.2%. DISCUSSION: We found that 3 of 5 Americans with constipation have never discussed their symptoms with a healthcare provider. Furthermore, the use of prescription medications for managing constipation symptoms is low because individuals mainly rely on over-the-counter therapies.

Low-fat/high-fibre diet prehabilitation improves anastomotic healing via the microbiome: an experimental model.

BACKGROUND: Both obesity and the presence of collagenolytic bacterial strains (Enterococcus faecalis) can increase the risk of anastomotic leak. The aim of this study was to determine whether mice chronically fed a high-fat Western-type diet (WD) develop anastomotic leak in association with altered microbiota, and whether this can be mitigated by a short course of standard chow diet (SD; low fat/high fibre) before surgery. METHODS: Male C57BL/6 mice were assigned to either SD or an obesogenic WD for 6 weeks followed by preoperative antibiotics and colonic anastomosis. Microbiota were analysed longitudinally after operation and correlated with healing using an established anastomotic healing score. In reiterative experiments, mice fed a WD for 6 weeks were exposed to a SD for 2, 4 and 6 days before colonic surgery, and anastomotic healing and colonic microbiota analysed. RESULTS: Compared with SD-fed mice, WD-fed mice demonstrated an increased risk of anastomotic leak, with a bloom in the abundance of Enterococcus in lumen and expelled stool (65-90 per cent for WD versus 4-15 per cent for SD; P = 0·010 for lumen, P = 0·013 for stool). Microbiota of SD-fed mice, but not those fed WD, were restored to their preoperative composition after surgery. Anastomotic healing was significantly improved when WD-fed mice were exposed to a SD diet for 2 days before antibiotics and surgery (P < 0·001). CONCLUSION: The adverse effects of chronic feeding of a WD on the microbiota and anastomotic healing can be prevented by a short course of SD in mice. Surgical relevance Worldwide, enhanced recovery programmes have developed into standards of care that reduce major complications after surgery, such as surgical-site infections and anastomotic leak. A complementary effort termed prehabilitation includes preoperative approaches such as smoking cessation, exercise and dietary modification. This study investigated whether a short course of dietary prehabilitation in the form of a low-fat/high-fibre composition can reverse the adverse effect of a high-fat Western-type diet on anastomotic healing in mice. Intake of a Western-type diet had a major adverse effect on both the intestinal microbiome and anastomotic healing following colonic anastomosis in mice. This could be reversed when mice received a low-fat/high-fibre diet before operation. Taken together, these data suggest that dietary modifications before major surgery can improve surgical outcomes via their effects on the intestinal microbiome.

ANTECEDENTES: Tanto la obesidad como la presencia de cepas bacterianas colagenolíticas (Enterococcus faecalis) pueden aumentar el riesgo de fuga anastomótica. El objetivo de este estudio fue determinar si los ratones alimentados durante un tiempo prolongado con una dieta de tipo occidental con alto contenido en grasas (western type diet, WD) desarrollaban una fuga anastomótica en asociación con una microbiota alterada, así como determinar si una dieta estándar preoperatoria de corta duración baja en grasa/alta en fibra (standard diet, SD) podía mitigar la aparición de fuga. MÉTODOS: Ratones machos C57BL/6 obtenidos de Charles River fueron asignados aleatoriamente a una dieta chow estándar (SD) o a una dieta de tipo occidental obesogénica (WD) durante 6 semanas, seguida de la administración preoperatoria de antibióticos y la realización de una anastomosis en el colon. La microbiota se analizó longitudinalmente después de la operación y se correlacionó con la curación utilizando una puntuación de cicatrización anastomótica ya establecida. En experimentos repetidos, los ratones con una WD durante 6 semanas fueron expuestos a una SD durante 2, 4 y 6 días antes de la cirugía de colon, analizándose la cicatrización de la anastomosis y la microbiota del colon. RESULTADOS: Los ratones alimentados con WD en comparación con los alimentados con SD presentaron un mayor riesgo de fuga anastomótica con un rápido incremento en la abundancia de Enterococcus (65-90% para WD versus 4-15% para SD, P < 0,01). La microbiota de ratones alimentados con SD, pero no con WD, se restableció a su composición preoperatoria después de la operación. La cicatrización anastomótica mejoró significativamente cuando los ratones alimentados con WD fueron expuestos a una dieta SD durante 2 días antes del tratamiento antibiótico y de la cirugía (P < 0,01). CONCLUSIÓN: En ratones, los efectos adversos de una alimentación crónica con una WD sobre la microbiota y la cicatrización anastomótica se pueden prevenir mediante una SD de corta duración.

Interventions for preventing postpartum constipation.

BACKGROUND: Postpartum constipation, with symptoms, such as pain or discomfort, straining, and hard stool, is a common condition affecting mothers. Haemorrhoids, pain at the episiotomy site, effects of pregnancy hormones, and haematinics used in pregnancy can increase the risk of postpartum constipation. Eating a high-fibre diet and increasing fluid intake are usually encouraged. Although laxatives are commonly used in relieving constipation, the effectiveness and safety of available interventions for preventing postpartum constipation should be ascertained. This is an update of a review first published in 2015. OBJECTIVES: To evaluate the effectiveness and safety of interventions for preventing postpartum constipation. SEARCH METHODS: We searched Cochrane Pregnancy and Childbirth's Trials Register, and two trials registers ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (ICTRP) (7 October 2019), and screened reference lists of retrieved trials. SELECTION CRITERIA: We considered all randomised controlled trials (RCTs) comparing any intervention for preventing postpartum constipation versus another intervention, placebo, or no intervention in postpartum women. Interventions could include pharmacological (e.g. laxatives) and non-pharmacological interventions (e.g. acupuncture, educational and behavioural interventions). Quasi-randomised trials and cluster-RCTs were eligible for inclusion; none were identified. Trials using a cross-over design were not eligible. DATA COLLECTION AND ANALYSIS: Two review authors independently screened the results of the search to select potentially relevant trials, extracted data, assessed risk of bias, and the certainty of the evidence, using the GRADE approach. We did not pool results in a meta-analysis, but reported them per study. MAIN RESULTS: We included five trials (1208 postpartum mothers); three RCTs and two quasi-RCTs. Four trials compared a laxative with placebo; one compared a laxative plus a bulking agent versus the same laxative alone, in women who underwent surgical repair of third degree perineal tears. Trials were poorly reported, and four of the five trials were published over 40 years ago. We judged the risk of bias to be unclear for most domains. Overall, we found a high risk of selection and attrition bias. Laxative versus placebo We included four trials in this comparison. Two of the trials examined the effects of laxatives that are no longer used; one has been found to have carcinogenic properties (Danthron), and the other is not recommended for lactating women (Bisoxatin acetate); therefore, we did not include their results in our main findings. None of the trials included in this comparison assessed our primary outcomes: pain or straining on defecation, incidence of postpartum constipation, or quality of life; or many of our secondary outcomes. A laxative (senna) may increase the number of women having their first bowel movement within 24 hours after delivery (risk ratio (RR) 2.90, 95% confidence interval (CI) 2.24 to 3.75; 1 trial, 471 women; low-certainty evidence); may have little or no effect on the number of women having their first bowel movement on day one after delivery (RR 0.94, 95% CI 0.72 to 1.22; 1 trial, 471 women; very low-certainty evidence); may reduce the number of women having their first bowel movement on day two (RR 0.23, 95% CI 0.11 to 0.45; 1 trial, 471 women; low-certainty evidence); and day three (RR 0.05, 95% CI 0.00 to 0.89; 1 trial, 471 women; low-certainty evidence); and may have little or no effect on the number of women having their first bowel movement on day four after delivery (RR 0.22, 95% CI 0.03 to 1.87; 1 trial, 471 women; very low-certainty evidence), but some of the evidence is very uncertain. Adverse effects were poorly reported. Low-certainty evidence suggests that the laxative (senna) may increase the number of women experiencing abdominal cramps (RR 4.23, 95% CI 1.75 to 10.19; 1 trial, 471 women). Very low-certainty evidence suggests that laxatives taken by the mother may have little or no effect on loose stools in the baby (RR 0.62, 95% CI 0.16 to 2.41; 1 trial, 281 babies); or diarrhoea (RR 2.46, 95% CI 0.23 to 26.82; 1 trial, 281 babies). Laxative plus bulking agent versus laxative only Very low-certainty evidence from one trial (147 women) suggests no evidence of a difference between these two groups of women who underwent surgical repair of third degree perineal tears; only median and range data were reported. The trial also reported no evidence of a difference in the incidence of postpartum constipation (data not reported), but did not report on quality of life. Time to first bowel movement was reported as a median (range); very low-certainty evidence suggests little or no difference between the two groups. A laxative plus bulking agent may increase the number of women having any episode of faecal incontinence during the first 10 days postpartum (RR 1.81, 95% CI 1.01 to 3.23; 1 trial, 147 women; very low-certainty evidence). The trial did not report on adverse effects of the intervention on babies, or many of our secondary outcomes. AUTHORS' CONCLUSIONS: There is insufficient evidence to make general conclusions about the effectiveness and safety of laxatives for preventing postpartum constipation. The evidence in this review was assessed as low to very low-certainty evidence, with downgrading decisions based on limitations in study design, indirectness and imprecision. We did not identify any trials assessing educational or behavioural interventions. We identified four trials that examined laxatives versus placebo, and one that examined laxatives versus laxatives plus stool bulking agents. Further, rigorous trials are needed to assess the effectiveness and safety of laxatives during the postpartum period for preventing constipation. Trials should assess educational and behavioural interventions, and positions that enhance defecation. They should report on the primary outcomes from this review: pain or straining on defecation, incidence of postpartum constipation, quality of life, time to first bowel movement after delivery, and adverse effects caused by the intervention, such as: nausea or vomiting, pain, and flatus.