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The Cochrane Database of Systematic... Sep 2023Cystic fibrosis (CF) is a multisystem disease; the importance of growth and nutritional status is well established given their implications for lung function and overall... (Review)
Review
BACKGROUND
Cystic fibrosis (CF) is a multisystem disease; the importance of growth and nutritional status is well established given their implications for lung function and overall survivability. Furthermore, it has been established that intestinal microbial imbalance and inflammation are present in people with CF. Oral prebiotics are commercially available substrates that are selectively utilised by host intestinal micro-organisms and may improve both intestinal and overall health.
OBJECTIVES
To evaluate the benefits and harms of prebiotics for improving health outcomes in children and adults with CF.
SEARCH METHODS
We searched the Cochrane Cystic Fibrosis Trials Register compiled from electronic database searches and handsearching of journals and conference abstract books. We also searched the reference lists of relevant articles and reviews. Date of last search: 19 October 2022. We also searched PubMed and online trials registries. Date of last search: 13 January 2023.
SELECTION CRITERIA
Randomised controlled trials (RCTs) and quasi-RCTs assessing the efficacy of prebiotics in children and adults with CF. We planned to only include the first treatment period from cross-over RCTs, regardless of washout period.
DATA COLLECTION AND ANALYSIS
We did not identify any relevant trials.
MAIN RESULTS
We did not identify any relevant trials for inclusion in this review.
AUTHORS' CONCLUSIONS
This review did not find any evidence for the use of prebiotics in people with CF. Until such evidence is available, it is reasonable for clinicians to follow any local guidelines and to discuss the use of dietary prebiotics with their patients. Large and robust RCTs assessing the dietary prebiotics of inulin or galacto-oligosaccharides or fructo-oligosaccharides, or any combination of these, are needed. Such studies should be of at least 12 months in duration and assess outcomes such as growth and nutrition, gastrointestinal symptoms, pulmonary exacerbations, lung function, inflammatory biomarkers, hospitalisations, intestinal microbial profiling, and faecal short-chain fatty acids. Trials should include both children and adults and aim to be adequately powered to allow for subgroup analysis by age.
Topics: Adult; Child; Humans; Cystic Fibrosis; Feces; Hospitalization; Inflammation; Nutritional Status; Prebiotics
PubMed: 37753791
DOI: 10.1002/14651858.CD015236.pub2 -
Advances in Nutrition (Bethesda, Md.) Nov 2023The COVID-19 pandemic highlighted the importance of healthy diets in the management of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and... (Review)
Review
The COVID-19 pandemic highlighted the importance of healthy diets in the management of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and COVID-19. Evidence suggests the influence of diet and dietary patterns during post-COVID-19, and the impact of the COVID-19 pandemic on dietary habits and quality. However, limited evidence lies on the association between a healthy diet, and risk of SARS-CoV-2 infection or COVID-19. This study aimed to conduct a systematic review of observational studies to examine the association between diet quality, and the risk of SARS-CoV-2 infection or COVID-19 among adult populations. 6158 research articles from Scopus, EMBASE, PubMed, and MEDLINE databases were identified for eligibility. Only observational studies were included. Study quality was assessed using the National Institutes of Health Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies. Thirteen studies were included (4 with SARS-CoV-2 infection and 9 with COVID-19 as the outcome); 3 were case-control, 3 were cross-sectional, and 7 were prospective studies. Adherence to Mediterranean diet was examined as exposure in 7 studies, and was associated with decreased risk of SARS-CoV-2 infection in 2 studies, with estimates varying from 12% to 22%, while COVID-19 risk or severity was found to be reduced in 3 studies with odds ratios (ORs) ranging from 36% to 77%. The Dietary Approaches to Stop Hypertension diet was inversely associated with COVID-19 hospitalization (OR: 0.19; 95% CI: 0.07, 0.55), whereas a healthy plant-based diet had an inverse association with both COVID-19 infection (hazard ratio [HR]: 0.91; 95% CI: 0.88, 0.94) and severity (HR: 0.59; 95% CI: 0.47, 0.74). Studies examining individual food groups generally found lower risk of infection or COVID-19 in association with larger dietary intakes of fruits, vegetables, and fiber. The overall findings of the observational studies in this review support the concept that nutritious diets might lower the risk of SARS-CoV-2 infection or COVID-19. This study was registered at PROSPERO as CRD42023397371.
Topics: United States; Adult; Humans; COVID-19; SARS-CoV-2; Pandemics; Prospective Studies; Diet, Healthy; Observational Studies as Topic
PubMed: 37748553
DOI: 10.1016/j.advnut.2023.09.006 -
Journal of Affective Disorders Dec 2023Anxiety can adversely affect human well-being. This meta-analysis aimed to evaluate the effects of interventions that alter the gut microbes (including probiotics,... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Anxiety can adversely affect human well-being. This meta-analysis aimed to evaluate the effects of interventions that alter the gut microbes (including probiotics, prebiotics, and synbiotics) on anxiety.
METHODS
A systematic meta-analysis of the effects of probiotics, prebiotics, and synbiotics on anxiety was conducted by searching randomized controlled trials (RCTs) in 13 databases. The primary outcomes were the pre- and post-intervention anxiety scores in the intervention and placebo groups. Anxiety scores were extracted as standard mean differences (SMDs) and pooled based on a random effects model. Subgroup analyses of anxiety scales, health status, gastrointestinal symptoms, flora strains, treatment type, probiotic dose, region, and treatment duration were also performed.
RESULTS
29 RCTs (2035 participants) were included, revealing that both probiotics and synbiotics significantly reduced anxiety scores. Additionally, anxiety scores did not significantly reduce when comparing prebiotics and placebos.
LIMITATIONS
Owing to the small combined effect size of probiotic/prebiotic/synbiotic treatments and the relatively few studies on prebiotics and synbiotics included in the analysis, the findings of probiotic/prebiotic/synbiotic treatments are preliminary.
CONCLUSIONS
Our study indicated that probiotics and synbiotics can reduce anxiety scores; however, it might be premature to conclude their clinical efficacy in alleviating anxiety due to the small effect size. There is no consensus regarding the optimal dose, treatment duration, treatment type, or probiotic strain to improve anxiety. Moreover, the mechanisms by which probiotics and synbiotics improve anxiety remain unclear. More RCTs are needed to determine the mechanisms of action and to identify appropriate markers to clarify their effects.
Topics: Humans; Synbiotics; Prebiotics; Randomized Controlled Trials as Topic; Probiotics; Anxiety
PubMed: 37734624
DOI: 10.1016/j.jad.2023.09.018 -
Frontiers in Nutrition 2023The effect of viscous soluble dietary fiber on glucose and lipid metabolism in type 2 diabetes mellitus (T2DM) remains controversial, and the dose-response relationship...
Effect of viscous soluble dietary fiber on glucose and lipid metabolism in patients with type 2 diabetes mellitus: a systematic review and meta-analysis on randomized clinical trials.
BACKGROUND
The effect of viscous soluble dietary fiber on glucose and lipid metabolism in type 2 diabetes mellitus (T2DM) remains controversial, and the dose-response relationship of its effect on blood glucose and blood lipid level is still unclear.
METHODS
We conducted comprehensive searches in several databases up to 17 January 2023. We conducted a dose-response analysis of randomized controlled trials (RCTs) to investigate the effect of viscous dietary fiber on glucose and lipid metabolism in patients with T2DM.
RESULTS
Statistical significance was observed in the decreases of glycosylated hemoglobin (HbA1c) (mean difference) [MD = -0.47; 95%CI: (-0.66, -0.27)], fasting blood glucose (FBG) [MD = -0.93; 95%CI: (-1.46, -0.41)], total cholesterol (TC) [MD = -0.33; 95%CI: (-0.46, -0.21)], and low-density lipoprotein and cholesterol (LDL-C) [MD = -0.24; 95%CI: (-0.35, -0.13)]. Contrarily, no difference was observed regarding the level of high-density lipoprotein cholesterol (HDL-C) or triglyceride (TG). In addition, the effect on fasting insulin remains unclear. Results from the subgroup analyses showed that an intervention duration longer than 6 weeks had a significant effect on the HbA1c level; a treatment dosage higher than 8.3 g/day had a significant effect on the FBG level.
CONCLUSIONS
Supplementation of viscous dietary fiber is beneficial to control blood glucose and blood lipid in T2DM.
PubMed: 37720378
DOI: 10.3389/fnut.2023.1253312 -
International Journal of Obesity (2005) Nov 2023Probiotics are commonly used after bariatric surgery. However, uncertainty remains regarding their effects. The purpose of this systematic review was to assess the... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Probiotics are commonly used after bariatric surgery. However, uncertainty remains regarding their effects. The purpose of this systematic review was to assess the effect of probiotics in patients with morbid obesity undergoing bariatric surgery.
METHODS
PubMed, Cochrane Library, Embase, Science Direct, and Web of Science were searched from inception to April 4, 2023. No language restrictions were applied. Relevant randomized controlled trials and controlled clinical trials were included. We used the aggregated data extracted from the trials and assessed the heterogeneity. When severe heterogeneity was detected, a random effect model was used. All stages of the review were done by independent authors.
RESULTS
We screened 2024 references and included 11 randomized controlled trials and controlled clinical trials. Compared with the protocol groups, probiotics showed significant effects on regulating aspartate amino transferase level (MD = -4.32 U/L; 95% CI [-7.10, -1.53], p = 0.002), triglycerides (MD = -20.16 mg/dL; 95% CI [-34.51, -5.82], p = 0.006), weight (MD = -1.99 kg; 95% CI [-3.97, -0.01], p = 0.05), vitamin B (MD = 2.24 pg/dL; 95% CI [-0.02, 4.51], p = 0.05), dietary energy (MD = -151.03 kcal; 95% CI [-215.68, -86.37], p < 0.00001), dietary protein (MD = -4.48 g/day, 95% CI [-8.76, -0.20], p = 0.04), dietary carbohydrate (MD = -34.25 g/day, 95% CI [-44.87, -23.62], p < 0.00001), and dietary fiber (MD = -2.17 g/day, 95% CI [-3.21, -1.14], p < 0.0001). There were no severe side effects related to probiotics.
CONCLUSIONS
Our meta-analysis suggested that probiotics may delay the progression of liver function injury, improve lipid metabolism, reduce weight, and reduce food intake, although the effects on other indicators were insignificant. Probiotics may be helpful for patients undergoing bariatric surgery. The review was registered on PROSPERO (International prospective register of systematic reviews): CRD42023407970. No primary source of funding.
Topics: Humans; Obesity, Morbid; Probiotics; Dietary Fiber; Bariatric Surgery; Liver
PubMed: 37674033
DOI: 10.1038/s41366-023-01375-5 -
Frontiers in Nutrition 2023Dietary factors may affect the incidence of colorectal serrated polyps (SP). However, its effects on SP are unclear as epidemiological studies on this topic have showed...
BACKGROUND
Dietary factors may affect the incidence of colorectal serrated polyps (SP). However, its effects on SP are unclear as epidemiological studies on this topic have showed inconsistent results. The present systematic review and meta-analysis sought to evaluate the effects of dietary factors on SPs.
METHODS
Studies regarding the association between dietary factors and SPs were identified by searching PubMed, Cochrane library, Embase and Chinese Biomedical Literature database from inception until 27 February 2023. Search terms include serrated, hyperplastic, adenoma, polyps, colorectal, rectal, rectum and risk. Heterogeneity was assessed using statistics. The meta-analysis was conducted by using a random-effects model, and the pooled effects were expressed with odds ratios (OR) and 95% confidence intervals (95% CI). Probable sources of heterogeneity were identified through meta-regression. Subgroup analysis were based on lesion types, study designs, countries, and so on.
RESULTS
28 studies were ultimately eligible after scanning, and five dietary factors including vitamin D, calcium, folate, fiber and red or processed meat were excerpted. Higher intakes of vitamin D (OR = 0.95, 95%CI:0.90-1.02), calcium (OR = 0.97, 95%CI: 0.91-1.03) and folate (OR = 0.82, 95% CI: 0.6-1.13) were not significantly associated with SP. Fiber intake (OR = 0.90, 95% CI: 0.82-0.99) was a protective factor against SPs. Red meat intake increased the risk of SPs by 30% for the highest versus lowest intakes (OR = 1.30, 95% CI: 1.13-1.51). For different lesion types, higher folate intake was associated with a decreased risk of HPs (OR = 0.59, 95%CI: 0.44-0.79), and higher vitamin D intake decreased the risk of SPs including SSA/P (OR = 0.93, 95%CI: 0.88-0.98).
CONCLUSIONS
Higher dietary fiber intake plays an effective role in preventing SP, while red meat intake is associated with an increased risk of SP. This evidence provides guidance for us to prevent SP from a dietary perspective.
SYSTEMATIC REVIEW REGISTRATION
https://www.crd.york.ac.uk/prospero/display_record.php?, RecordID=340750.
PubMed: 37575321
DOI: 10.3389/fnut.2023.1187539 -
Nutrition Reviews May 2024Nonalcoholic fatty liver disease (NAFLD) is considered the leading cause of chronic liver disease worldwide. To date, no confirmed medication is available for the... (Meta-Analysis)
Meta-Analysis
CONTEXT
Nonalcoholic fatty liver disease (NAFLD) is considered the leading cause of chronic liver disease worldwide. To date, no confirmed medication is available for the treatment of NAFLD. Previous studies showed the promising effects of gut microbiome-targeted therapies; however, the results were controversial and the strength of the evidence and their clinical significance remained unclear.
OBJECTIVES
This umbrella study summarizes the results of meta-analyses investigating the effects of probiotics, prebiotics, and synbiotics on liver enzymes in the NAFLD population.
DATA SOURCE
A comprehensive search of the PubMed, Scopus, Web of Science, and Cochrane Library databases was done up to December 20, 2022, to find meta-analyses on randomized control trials reporting the effects of gut microbial therapy on patients with NAFLD.
DATA EXTRACTION
Two independent investigators extracted data on the characteristics of meta-analyses, and any discrepancies were resolved by a third researcher. The AMSTAR2 checklist was used for evaluating the quality of studies.
DATA ANALYSIS
A final total of 15 studies were included in the analysis. Results showed that microbiome-targeted therapies could significantly reduce levels of alanine aminotransferase (ALT; effect size [ES], -10.21; 95% confidence interval [CI], -13.29, -7.14; P < 0.001), aspartate aminotransferase (AST; ES, -8.86; 95%CI, -11.39, -6.32; P < 0.001), and γ-glutamyltransferase (ES, -5.56; 95%CI, -7.92, -3.31; P < 0.001) in patients with NAFLD. Results of subgroup analysis based on intervention showed probiotics could significantly reduce levels of AST (ES, -8.69; 95%CI, -11.01, -6.37; P < 0.001) and ALT (ES, -9.82; 95%CI, -11.59, -8.05; P < 0.001). Synbiotics could significantly reduce levels of AST (ES, -11.40; 95%CI, -13.91, -8.88; P < 0.001) and ALT (ES, -11.87; 95%CI, -13.80, -9.95; P < 0.001). Prebiotics had no significant effects on AST and ALT levels (ES, -2.96; 95%CI, -8.12, 2.18, P = 0.259; and ES, -4.69; 95%CI, -13.53, 4.15, P = 0.299, respectively).
CONCLUSION
Gut microbiome-targeted therapies could be a promising therapeutic approach in the improvement of hepatic damage in patients with NAFLD. However, more studies are needed to better determine the best bacterial strains, duration of treatment, and optimum dosage of gut microbiome-targeted therapies in the treatment of the NAFLD population.
SYSTEMATIC REVIEW REGISTRATION
PROSPERO registration no. CRD42022346998.
Topics: Humans; Alanine Transaminase; Aspartate Aminotransferases; Gastrointestinal Microbiome; Liver; Non-alcoholic Fatty Liver Disease; Prebiotics; Probiotics; Synbiotics
PubMed: 37550264
DOI: 10.1093/nutrit/nuad086 -
Current Medical Research and Opinion Sep 2023Chronic constipation is a challenging functional gastrointestinal disorder that remains a global burden. Pharmacologic therapy, including laxatives and dietary fibers,... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
Chronic constipation is a challenging functional gastrointestinal disorder that remains a global burden. Pharmacologic therapy, including laxatives and dietary fibers, are suggested as lines of treatment. Recent trials introduced an orally ingested vibrating capsule (VC) as an eligible option for chronic constipation management.
METHODS
We conducted a literature search in English on electronic databases CENTRAL, PubMed, EMBASE, Scopus, and WOS until February 27th, 2023. RevMan was used to perform the meta-analysis. The results were reported as risk ratios (RRs), mean differences (MDs), and 95% confidence intervals (CIs). The study protocol was registered in PROSPERO with ID: (CRD42023409422).
RESULTS
Three RCTs with a total of 601 patients were included in our analysis. There was no difference between the VC and placebo in responder rate (RR: 1.37 with 95% CI [0.82, 2.28], = .22), CSBM change from baseline (MD: 0.21 with 95% CI [-0.26, 0.69], = .38), SBM change from baseline (MD: 0.14 with 95% CI [-0.22, 0.49], = .46), and the incidence of any adverse event (RR: 1.45 with a 95% CI of [0.79, 2.63], = .23). However, VC was associated with increased vibration sensation (RR: 17.23, 95% CI [3.29, 90.20], = .0008).
CONCLUSIONS
VC was not effective to improve bowel movement in patients with functional constipation with no difference in response rate. However, evidence is still uncertain, with only three small RCTs that yielded heterogenous findings, mainly due to the different vibration protocols. Also, our findings suggest that VC is safe and well-tolerated, with no significant harmful effects observed. Therefore, more large-scale RCTs are needed to confirm the efficacy and safety of VC in patients with functional constipation, determining the most effective dose, frequency, and duration of treatment.
Topics: Humans; Capsules; Randomized Controlled Trials as Topic; Constipation; Laxatives; Dietary Fiber
PubMed: 37526021
DOI: 10.1080/03007995.2023.2243219 -
Cureus Jun 2023High cholesterol levels are a significant risk factor for heart disease, the leading cause of death worldwide. Lowering cholesterol plays a crucial role in maintaining... (Review)
Review
High cholesterol levels are a significant risk factor for heart disease, the leading cause of death worldwide. Lowering cholesterol plays a crucial role in maintaining good health. One approach to reducing cholesterol is through dietary modifications, and avocados have been recognized as a potential food choice for this purpose. Avocados are rich in monounsaturated fatty acids (MUFAs), fiber, and plant sterols, which have cholesterol-lowering effects. Incorporating avocados into a low-fat diet can be beneficial. This study design followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines and conducted databases in Cochrane, SCOPUS, PubMed, and Web of Science up until May 2023, combining keywords related to avocados and cardiovascular diseases (CVDs). The study focused on randomized clinical trials (RCTs) and excluded observational studies, meta-analyses, surveys, abstracts, and reviews. Seven RCTs were included in the study, all reporting total cholesterol (TC) levels. The findings of the study showed that individuals who followed an avocado diet experienced reduced TC levels compared to those who followed a habitual diet or a low-fat diet. The avocado group exhibited lower TC levels compared to the control group in both the habitual diet and low-fat diet subgroups. When considering high-density lipoprotein (HDL) levels, the control group had higher HDL levels than the avocado group in the habitual diet subgroup, while the avocado group had higher HDL levels than the control group in the low-fat diet subgroup. In both the habitual diet and low-fat diet subgroups, the avocado group had lower levels of low-density lipoprotein (LDL) compared to the control group. The study concluded that incorporating avocados into the diet can be a beneficial dietary strategy for individuals aiming to lower their cholesterol levels and promote heart health. The avocado diet was associated with decreased LDL levels, but it did not significantly impact triglyceride (TG) levels or fasting glucose levels. Systolic blood pressure values showed minimal changes with the avocado diet.
PubMed: 37525782
DOI: 10.7759/cureus.41189 -
Nutrients Jul 2023Crohn's disease (CD) is a subtype of inflammatory bowel disease (IBD). CD is a health problem in Western countries such as the US and European nations and is an... (Meta-Analysis)
Meta-Analysis Review
Crohn's disease (CD) is a subtype of inflammatory bowel disease (IBD). CD is a health problem in Western countries such as the US and European nations and is an idiopathic disease; however, certain cases of CD have been associated with intestinal dysbiosis. A systematic review with a meta-analysis was carried out to determine the efficacy of a diet rich in fiber with or without cointervention to improve remission rates for CD. The literature in the PubMed, Scopus, Web of Science, and ClinicalTrials databases was reviewed. The quality of the studies was evaluated using the Johanna Briggs Institute (JBI) scale. This review was conducted in accordance with the structure outlined in the PRISMA statement. In addition, a meta-analysis was performed with a 95% confidence interval (CI) and a random effects model. Eleven studies were included, totaling 2389 patients with CD. Applying a diet rich in fiber with or without the administration of routine therapies improved CD remission rates. Data regarding CD activity, remission time, and adverse effects derived from fiber consumption were analyzed. Consumption of fiber in the diet could improve remission rates for CD patients who receive or do not receive other treatment to maintain remission.
Topics: Humans; Crohn Disease; Dietary Fiber; Diet; Remission Induction
PubMed: 37513532
DOI: 10.3390/nu15143114