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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 -
Nutrition Journal Oct 2023Pervious epidemiologic evidence indicates that soluble fiber is protective against hypertention: however, randomized controlled trials (RCTs) have presented varying... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVES
Pervious epidemiologic evidence indicates that soluble fiber is protective against hypertention: however, randomized controlled trials (RCTs) have presented varying results. In the present study, we aimed to conduct a systematic review and dose-response meta-analysis to summarize published RCTs which assess the effect of soluble fiber supplementation on systolic blood pressure (SBP) and diastolic blood pressure (DBP).
METHODS
Scopus, PubMed, and ISI Web of Sciences were searched to identify relevant studies up to Aug 2022. We estimated the change in blood pressure for each 5 g/d increment in soluble fiber supplementation in each trial and then calculated the weighted mean difference (WMD) and 95%CI using a random-effects model. We estimated dose-dependent effects using a dose-response meta-analysis of differences in means. The risk of bias for study was assessed using the Cochrane tool. Publication bias was evaluated via funnel plot and Begg's test and Egger's test.
RESULTS
Eighty-three eligible studies with total sample size of 5,985 participants were included in the meta-analysis. Soluble fiber supplementation significantly decreased SBP (WMD: -1.36 mmHg, 95% CI: -2.13 to -0.60, P < 0.001; I = 47.1%, P < 0.001) and DBP (WMD: -0.72 mmHg, 95% CI: -1.26 to -0.18, P = 0.009; I = 45.4%, P < 0.001). Each 5 g/d increment in soluble fiber supplementation had a significant reduction in SBP (WMD: -0.54 mmHg; 95%CI: -0.86, -0.22, P = 0.001; I = 52.2, P < 0.001) and DBP (WMD: -0.28 mmHg; 95%CI: -0.49, -0.80, P = 0.007; I = 43.1%, P < 0.001). The levels of SBP decreased proportionally with the increase in soluble fiber supplementation up to 20 g/d (MD: -1.79 mmHg, 95%CI: -2.86, -0.71).
CONCLUSION
Current evidence indicated the beneficial effect of soluble fiber supplementation on blood pressure. Our findings suggest that soluble fiber supplementation could contribute to the management of hypertension and the reduction of cardiovascular disease risk.
Topics: Adult; Humans; Blood Pressure; Dietary Supplements; Randomized Controlled Trials as Topic; Hypertension; Bias
PubMed: 37833676
DOI: 10.1186/s12937-023-00879-0 -
Frontiers in Nutrition 2023To conduct a systematic review and meta-analysis of prospective cohort studies to investigate the association between total, vegetable, fruit, cereal, soluble and...
Dietary intake of total vegetable, fruit, cereal, soluble and insoluble fiber and risk of all-cause, cardiovascular, and cancer mortality: systematic review and dose-response meta-analysis of prospective cohort studies.
OBJECTIVES
To conduct a systematic review and meta-analysis of prospective cohort studies to investigate the association between total, vegetable, fruit, cereal, soluble and insoluble fiber intake and risk of all causes, cardiovascular disease (CVD), and cancer mortality and quantitatively assess the dose-response relation.
METHODS
Eligible studies were identified by searching PubMed, Embase and Web of science before August 2023. Random effects models were used to calculate summary relative risk (RR) and 95% confidence intervals (CI) and restricted cubic splines to model the linear/non-linear association.
RESULTS
The summary RR for all-cause, CVD and cancer mortality of dietary fiber was 0.90 (95% CI: 0.86,0.93), 0.87 (0.84,0.91), 0.91 (0.88,0.93), respectively. Significant association was observed for all-cause and CVD mortality with fruit, vegetable cereal and soluble fiber intake and cancer mortality with cereal fiber intake. No significant association was found for insoluble fiber, vegetable or fruit fiber intake and cancer mortality. Dose-response analysis showed a significant non-linear relation of dietary fiber intake with all-cause mortality, and linear relation for others.
CONCLUSIONS
Higher dietary fiber including different type and food sources of fiber intake were associated with lower risk of mortality. Our findings provide more comprehensive evidence on dietary fiber intake with mortality.
SYSTEMATIC REVIEW REGISTRATION
https://www.crd.york.ac.uk/prospero, identifier: CRD42022338837.
PubMed: 37854351
DOI: 10.3389/fnut.2023.1153165 -
Nutrients Sep 2023Irritable bowel syndrome (IBS) is a chronic gastrointestinal disorder characterized by abdominal pain, bloating, and changes in bowel habits. Various dietary factors... (Review)
Review
BACKGROUND
Irritable bowel syndrome (IBS) is a chronic gastrointestinal disorder characterized by abdominal pain, bloating, and changes in bowel habits. Various dietary factors have been implicated in the pathogenesis and management of IBS symptoms. This systematic review aims to evaluate the effects of polyphenols, minerals, fibers, and fruits on the symptoms and overall well-being of individuals with IBS.
MATERIALS AND METHODS
A comprehensive literature search was conducted in several electronic databases, including PubMed, Scopus, and Web of Science. Studies published up until July 2023 were included.
RESULTS
The selected studies varied in terms of study design, participant characteristics, intervention duration, and outcome measures. Overall, the findings suggest that dietary interventions involving polyphenols, minerals, fibers, and fruits can have a positive impact on IBS symptoms. Dietary fiber supplementation, particularly soluble fiber, has been associated with reduced bloating and enhanced stool consistency.
CONCLUSIONS
This systematic review provides evidence supporting the beneficial effects of polyphenols, minerals, fibers, and fruits in IBS patients. These dietary components hold promise as complementary approaches for managing IBS symptoms. However, due to the heterogeneity of the included studies and the limited number of high-quality randomized controlled trials, further well-designed trials are warranted to establish the optimal dosages, duration, and long-term effects of these interventions. Understanding the role of specific dietary components in IBS management may pave the way for personalized dietary recommendations and improve the quality of life for individuals suffering from this complex disorder.
Topics: Humans; Fruit; Polyphenols; Irritable Bowel Syndrome; Quality of Life; Minerals; Flatulence
PubMed: 37764853
DOI: 10.3390/nu15184070 -
Nutrients Sep 2023Periodontitis is a chronic multifactorial inflammatory disease, that leads to tooth loss and is associated with other systemic diseases. The role of dietary fibre in the... (Review)
Review
BACKGROUND
Periodontitis is a chronic multifactorial inflammatory disease, that leads to tooth loss and is associated with other systemic diseases. The role of dietary fibre in the prevention and management of periodontal diseases is not well understood. The objective of this systematic review and meta-analysis was to assess how an intake of dietary fibre affects periodontal diseases in humans and any concomitant effects on systemic inflammation.
METHODOLOGY
Human interventional studies investigating the effects of oral fibre intake on various clinical parameters of periodontal diseases were included. Search strategy with MeSH and free-text search terms was performed on the following database: CINAHL Complete, EMBASE, MEDLINE, SciVerse Scopus, and Web of Science Core Collection on 21 October 2021 and updated on 19 February 2023 to identify relevant studies. Articles were filtered using the Covidence© web-based platform software. Data were pooled using random effects meta-analysis.
RESULTS
From all databases, a total of 19,971 studies were obtained. Upon title and abstract screening, 101 studies were included for full-text screening. Upon full-text screening, six studies were included for analysis. Of these, five were randomised controlled trials, and one was a sequential feeding trial involving fibre-rich daily diet for a 4-8 weeks period. Fibre-rich dietary intervention significantly reduced Clinical Attachment Loss/Level by 0.48 mm/tooth (95% CI, -0.63 to -0.33, < 0.001), Bleeding On Probing by 27.57% sites/tooth (95% CI -50.40 to -4.74, = 0.02), Periodontal Inflamed Surface Area by 173.88 mm (95% CI -288.06 to -59.69, = 0.003), Plaque Index by 0.02 (95% CI -0.04 to -0.00, = 0.04), and Gingival Index by 0.41 (95% -0.67 to -0.16, = 0.002). A non-significant reduction was observed for Probing Depth (-0.17 mm/tooth; 95% CI, -0.37 to 0.02, = 0.09).
CONCLUSIONS
Fibre-rich dietary interventions are associated with a reduction of clinical and particularly inflammatory markers of periodontal diseases. This shows a promising effect of dietary fibre as an intervention for inflammatory conditions like periodontal diseases.
PubMed: 37764817
DOI: 10.3390/nu15184034 -
Journal of Gastrointestinal and Liver... Sep 2023Inflammatory bowel disease (IBD) is a chronic inflammatory disorder of the gastrointestinal tract. Studies evaluated the effect of several diets on inflammatory markers...
BACKGROUND AND AIMS
Inflammatory bowel disease (IBD) is a chronic inflammatory disorder of the gastrointestinal tract. Studies evaluated the effect of several diets on inflammatory markers in IBD patients. Nevertheless, the results have been inconsistent. Therefore, we conducted this review to evaluate the effectiveness of dietary interventions on inflammatory markers in IBD.
METHODS
A comprehensive electronic literature search strategy using the PubMed, Embase, and Scopus was conducted in March 2023 and evaluated inflammatory markers included C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and fecal calprotectin (FC), as well as disease severity scores. We included full-text articles that met our inclusion and exclusion criteria. To evaluate the included studies, we used the NHLBI quality evaluation tools.
RESULTS
A total of 16 studies were included in our qualitative synthesis. Elemental and polymeric diets showed similar efficacy in reducing Crohn's disease activity index (CDAI) and CRP levels. On the other hand, most studies evaluating the effects of omega 3 fatty acids reported no significant improvement. Moreover, protein supplementation was not seen to improve ESR or CRP levels. Except for improvements in FC levels with IgG4-guided exclusion diet in CD patients with elevated CDAI levels, restrictive diets were successful in controlling functional abdominal symptoms but did not appear to have an impact on inflammation in most studies. Furthermore, disease severity scores, CRP, ESR, and FC levels did not significantly change when eating a high-fiber, low-refined-carb, low-fat diet.
CONCLUSIONS
Diet plays a vital role in managing IBD by impacting the inflammatory response. Among the interventions studied, enteral nutrition showed the most promising results, improving patients' inflammatory status. Restrictive diets effectively managed symptoms and clinical remission but had limited impact on inflammatory markers. Supplementing the diet with fatty acids, omega 3, or proteins did not definitively improve patients' condition or inflammation.
PubMed: 37494554
DOI: 10.15403/jgld-5090 -
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 -
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 -
Nutrients May 2024Understanding the relationship between the intake of sugars and diet quality can inform public health recommendations. This systematic review synthesized recent... (Review)
Review
Understanding the relationship between the intake of sugars and diet quality can inform public health recommendations. This systematic review synthesized recent literature on associations between sugar intake and diet quality in generally healthy populations aged 2 years or older. We searched databases from 2010 to 2022 for studies of any design examining associations between quantified sugar intake in the daily diet and dietary indexes (DIs) or micronutrient intakes. Different sugar types and diet quality measures were analyzed separately. We converted DI results to Pearson's correlations and grouped indexes with or without a free or added sugar component to facilitate cross-study comparisons. Meta-analysis was deemed inappropriate. From 13,869 screened records, we included 27 cross-sectional studies. NUQUEST risk of bias ratings were neutral ( = 18 studies) or poor ( = 9), and strength of evidence by the GRADE approach was very low due to study design. Most studies reported negative associations for added and free sugars with diet quality indexes ( ranging from -0.13 to -0.42) and nutrients of public health concern (fiber, vitamin D, calcium, potassium), while associations with total sugars were mixed. Due to cross-sectional study designs, the clinical relevance of these findings is unclear. Prospective studies are needed to minimize confounding and inform causal relationships.
Topics: Humans; Dietary Sugars; Diet; Cross-Sectional Studies; Female; Adult; Male; Diet, Healthy; Child; Middle Aged; Adolescent; Micronutrients; Child, Preschool; Young Adult; Aged
PubMed: 38892483
DOI: 10.3390/nu16111549 -
International Archives of Allergy and... 2024This scoping review aims to critically assess gaps in the current literature on atopic dermatitis (AD) by evaluating the overall effectiveness of dietary interventions.... (Review)
Review
BACKGROUND
This scoping review aims to critically assess gaps in the current literature on atopic dermatitis (AD) by evaluating the overall effectiveness of dietary interventions. Through a comprehensive analysis that follows the Preferred Reporting Item for Systematic Review and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR) guidelines, we conducted a thorough search on the Web of Science database in May 2023 using specific search strategies to identify all relevant studies on the research topic.
SUMMARY
A total of 104 full-text articles were included for review. Our synthesis identified seven notable categories of dietary interventions for AD, showcasing the diversity of interventions utilized. This includes vitamin supplementation, probiotic and prebiotic supplementation, dietary fat, biological compounds, foods from natural sources, major nutrients, and diet-related approaches. Further analyses stratified by targeted populations revealed a predominant focus on pediatrics, particularly in probiotic supplementation, and on adults, with an emphasis on vitamin D and E supplementation.
KEY MESSAGES
Despite most dietary interventions demonstrating overall effectiveness in improving AD severity and its subjective symptoms, several significant gaps were identified. There was a scarcity of studies on adults and whole-diet interventions, a prevalence of short-term interventions, heterogeneity in study outcomes, designs, and population, occasional disparity between statistical significance and clinical relevance, and a lack of a comprehensive multidisciplinary approach. Nonetheless, these findings offer valuable insights for future AD research, guiding additional evidence-driven dietary interventions and informing healthcare professionals, researchers, and individuals, advancing both understanding and management of AD.
Topics: Dermatitis, Atopic; Humans; Dietary Supplements; Probiotics; Diet; Prebiotics
PubMed: 38442688
DOI: 10.1159/000535903