Resistant Starch

BACKGROUND: Recent studies have shown that consumption of resistant starch (RS) has beneficial effects on the gut microbiota and immune function in patients with chronic kidney disease (CKD). The objective of this study was to evaluate the effects of RS on inflammation, uremic toxins, and renal function in patients with CKD through a systematic review and meta-analysis. METHODS: This systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA)-2020. We included randomized controlled trials comparing RS supplementation to placebo. The National Library of Medicine (PubMed), Excerpta Medica Database (Embase), Cochrane Library, Web of Science, China National Knowledge Internet (CNKI) databases, and two gray literature sources - Baidu and Research Gate, were used for search, up to 28 August 2024. There was no limitation on publication date, but only manuscripts published in English and Chinese were included. RESULTS: A total of 645 articles were retrieved. Ten articles met the inclusion criteria, and a total of 355 subjects were included. The analysis revealed that RS dietary intervention can significantly reduce indoxyl sulfate (IS) levels (SMD: -0.37, 95% confidence interval (CI): -0.70 to -0.04, p = .03) and blood urea nitrogen (BUN) levels (SMD: -0.30, 95% CI: -0.57 to -0.02, p = .03). There were no significant differences in the levels of interleukin-6 (IL-6), p-cresyl sulfate (p-CS), albumin, phosphorus, or tumor necrosis factor-α. CONCLUSIONS: The RS diet has potential beneficial effects on uremic toxin levels and renal function indices in patients with CKD. RS supplementation can reduce uremic toxin levels and improve renal function but does not reduce the inflammatory response in patients with CKD. Nevertheless, results should be cautiously interpreted, because of the limited sample size and different treatment dosages. Further research is necessary to corroborate the beneficial effects of RS2 supplementation in this population.

BACKGROUND: Soluble dietary fibers are known to reduce the levels of blood glucose and lipids in patients with type 2 diabetes mellitus (type 2 diabetes). Although several different dietary fiber supplements are utilized, to our knowledge, no previous study has ranked their efficacy yet. OBJECTIVES: We performed this systematic review and network meta-analysis to rank the effects of different types of soluble dietary fibers. METHODS: We performed our last systematic search on November 20, 2022. Eligible randomized controlled trials (RCTs) included adult patients with type 2 diabetes and compared the intake of soluble dietary fibers with that of another type of dietary fiber or no fiber. The outcomes were related to glycemic and lipid levels. The Bayesian method was used to perform a network meta-analysis and calculate the surface under the cumulative ranking (SUCRA) curve values to rank the interventions. The Grading of Recommendations Assessment, Development, and Evaluation system was applied to evaluate the overall quality of the evidence. RESULTS: We identified 46 RCTs, including data from 2685 patients who received 16 types of dietary fibers as intervention. Galactomannans had the highest effect on reducing the levels of HbA1c (SUCRA: 92.33%) and fasting blood glucose (SUCRA: 85.92%). With regard to fasting insulin level, HOMA-IR, β-glucans (SUCRA: 73.45%), and psyllium (SUCRA: 96.67%) were the most effective interventions. Galactomannans were ranked first in reducing the levels of triglycerides (SUCRA: 82.77%) and LDL cholesterol (SUCRA: 86.56%). With regard to cholesterol and HDL cholesterol levels, xylo-oligosaccharides (SUCRA: 84.59%) and gum arabic (SUCRA: 89.06%) were the most effective fibers. Most comparisons had a low or moderate certainty of evidence. CONCLUSIONS: Galactomannans were the most effective dietary fiber for reducing the levels of HbA1c, fasting blood glucose, triglycerides, and LDL cholesterol in patients with type 2 diabetes. This study was registered at PROSPERO as ID CRD42021282984.

BACKGROUND: Chronic kidney disease (CKD) is a main health problem associated with increased risk of cardiovascular disease, morbidity, and mortality. Recent studies shown that the progression of CKD may be related to the change of intestinal flora. Resistant starch (RS) is a type of dietary fiber that can act as a substrate for microbial fermentation. Some studies have found that the supplementation of RS can improve the intestinal flora disorder in CKD patients. However, the specific effect of RS on CKD patients remains controversial. OBJECTIVE: We designed this meta-analysis to identify and assess the effects of RS on patients with CKD. METHODS: A comprehensive search of MEDLINE, Embase, Web of Science, and Cochrane systematic review databases was conducted in January 2020, and all new trials were updated in August 2021. Randomized trials were collected to assess the effects of RS on patients with CKD. The weighted average effect size of the net change was calculated by using the random-effects model. RESULTS: The meta-analysis included 8 studies involving 301 participants. RS intake significantly reduced serum indolephenol sulfate (IS), blood phosphorus, IL-6, and uric acid levels in dialysis patients. The mean difference (MD) of serum IS (P = 0.0002) in the dialysis subgroup was -12.57 μmol/L (95% CI: -19.28, -5.86 μmol/L). The MD of blood phosphorus (P = 0.03) was -0.39 mg/dl (95% CI: -0.78, -0.01 mg/dl). The MD of serum uric acid (P = 0.004) between the dialysis subgroup and the nondialysis subgroup was -31.58 mmol/L (95% CI: -52.99, -10.17 mmol/L). The mean difference (MD) of IL-6 (P = 0.02) in the dialysis subgroup was -1.16 μmol/L (95% CI: -2.16, -0.16 μmol/L). However, there was no significant change of RS on hs-CRP, serum creatinine, blood urea nitrogen (BUN), blood paracresol sulfate, and blood lipid. CONCLUSIONS: The intake of RS reduced the serum IS, serum phosphorus, IL-6, and uric acid levels significantly in dialysis patients, while hs-CRP, serum creatinine, BUN, serum paracresol sulfate, and blood lipid showed no significant changes.

The aim of this systematic review and meta-analysis was to investigate the effects of resistant starch (RS) on inflammation and oxidative stress related indicators. PubMed, Embase and The Cochrane library were systematically searched to find randomized controlled trials (RCTs) of RS intervention up to February 2020. We used from the effect size, as estimated by the standardized mean difference (SMD) with 95% confidence intervals (95%CI) to perform the random method meta-analysis, with P value ≦0.05 as statistically significant. The 16 included trials with 17 effect sizes included a total of 739 participants in this paper. The intervention duration was from 2 weeks to 3 months. The analysis indicated that RS decreases the levels of tumor necrosis factor-α (TNF-α) (SMD = -0.711; 95%CI: -1.227, -0.194; P = 0.007) and interleukin 6 (IL-6) (SMD = -0.609; 95%CI: -0.924, -0.294; P < 0.001), increases total antioxidant capacity (TAC) (SMD = 2.543, 95% CI: 0.069: 5.017, P = 0.044). No significant effects on C-reactive protein (CRP) (SMD = -0.583; 95%CI: -1.270, 0.104; P = 0.096), superoxide dismutase (SOD) (SMD = 0.091; 95%CI: -0.156, 0.338; P = 0.471), and malondialdehyde (MDA) (SMD = -0.320; 95%CI: -0.907, 0.266; P = 0.285). Subgroup analysis shown that CRP level significant reduced in subjects from the east (SMD = -1.501; 95%CI: -2.662, -0.340; P = 0.011) or suffering from diseases (SMD: -1.057; 95%CI: -1.999, -0.115; P = 0.028).Supplemental data for this article is available online at https://doi.org/10.1080/01635581.2021.2019284.

BACKGROUND AND OBJECTIVES: Animal experiments showed that resistant starch (RS) had an antioxidant and antiinflammatory effect. However, clinical studies showed both insignificant and significant effects of RS on inflammation and oxidative stress. The purpose of this work is to conduct a systematic review and meta-analysis of previous randomized controlled trials (RCTs) to investigate these effects. METHODS AND STUDY DESIGN: A systematic literature search was conducted on Web of Science, Scopus, PubMed and Cochrane electronic databases, which included studies from the earliest date of the database to September 2021. Key inclusion criteria were: RCTs; reporting at least one inflammatory or oxidative stress biomarker as endpoint; more than seven day intervention. Key exclusion criteria were: using a mixture of RS and other functional food ingredients as intervention substance; inappropriate controls. RESULTS: A total of 16 RCTs including 706 subjects were included. RS supplementation significantly improved total antioxidant capacity [standard mean difference (SMD) (95% CI): 2.64 (0.34, 4.94), p=0.03], and significantly reduced blood malondialdehyde concentration [SMD (95% CI): -0.55 (- 0.94, -0.17), p=0.01]. RS supplementation significantly reduced blood C-reactive protein concentration in type 2 diabetes mellitus (T2DM) patients [SMD (95% CI): -0.35 (-0.65, -0.05), p=0.02]. RS consumption significantly reduced blood interlukin-6 and tumor necrosis factor- concentration if removing one distinct trial. CONCLUSIONS: RS supplementation may significantly reduce a few oxidative-stress and inflammation biomarkers such as malondialdehyde and C-reactive protein, particularly in T2DM patients. Future work should investigate the optimal dosage of RS supplementation for modulating oxidative stress and inflammation biomarkers related to T2DM.

BACKGROUND & AIMS: Although several clinical trials have assessed the effect of Resistant Starch (RS) supplementation on appetite, the results have been inconsistent. Therefore, this study aimed to assess the effect of RS on the healthy adults' rating of appetite. MATERIALS AND METHODS: To this end, Pubmed, CENTRAL, Web of science, Scopus, Medline, and Proquest were systematically searched to find the relevant randomized, and placebo-controlled human trials up to June 2019. As a result, the area under curve (AUC) and standard deviations of the participants' rating appetite were extracted from four eligible studies. RESULTS: Meta-analysis showed a lower appetite in RS group compared to the controls (weighted mean difference [WMD] = -1.375 mm min, 95% confidence interval [95%CI]: -1.673, -1.076). Since high heterogeneity was observed among the included studies (I2 = 94.5%, P < 0.001), subgroup analysis was carried out by RS dose, RS type, duration of supplementation, and time of AUC measuring. In studies that used RS dose of ≥25 gr, heterogeneity disappeared (P = 0.560, I2 = 0%). In such studies, a significant reduction was observed in rating of appetite (WMD = -4.513 mm min, 95%CI: -5.270, -3.755; P < 0.001) than studies with RS dose of <25 gr (WMD = -0.799 mm min, 95%CI: -1.123,-0.474; P < 0.001). Additionally, subgroup analysis based on the type of RS showed a significant decrease of appetite in studies that used RS2 (WMD = -4.808 mm min, 95%CI: -5.834, -3.782; P < 0.001) than RS1 (WMD = -0.128 mm min, 95%CI: -0.457, 0.202; P = 0.448). CONCLUSIONS: To decrease the rate of appetite more effectively, we suggest other researchers to identify RS dose and type.

Background: Resistant starch type 2 (RS2) has been documented to regulate gut microbiota and to improve the clinical outcomes of several diseases. However, whether RS2 may benefit patients with end-stage renal disease under maintenance hemodialysis (MHD) remains unknown. Methods: We conducted a systemic review and meta-analysis of randomized controlled trials (RCTs). Adult patients receiving MHD were treated with RS2 (CRD42020160332). The primary outcomes were changes of uremic toxins, and the secondary outcomes were changes of inflammatory indicators, albumin and phosphorus. Results: After screening 65 records, five RCTs (n = 179) were included. A significant decrease of blood urea nitrogen (weighted mean difference (WMD) = -6.91, 95% CI: -11.87 to -1.95, I2 = 0%, P = 0.006), serum creatinine (WMD = -1.11, 95% CI: -2.18 to -0.05, I2 = 44%, P = 0.04) and interleukin (IL)-6 in blood (standard mean difference (SMD) = -1.08, 95% CI: -1.64 to -0.53, I2 = 35%, P = 0.0001) was revealed in the RS2 group. Analyses of blood levels of uric acid, p-cresyl sulfate, indoxyl sulfate, high sensitive C-reaction protein, albumin and phosphorus yielded no significant difference. Conclusions: Our results suggest that RS2 may improve the residual renal function of patients under MHD and mitigate a proinflammatory response. © The author(s).

This study presents a meta-analysis of studies that investigate the effectiveness of chitosan administration on lifestyle-related disease in murine models. A total of 34 published studies were used to evaluate the effect of chitosan supplementation. The effect sizes for various items after chitosan administration were evaluated using the standardized mean difference. Using Cochran's Q test, the heterogeneity of effect sizes was assessed, after which a meta-ANOVA and -regression test was conducted to explain the heterogeneity of effect sizes using the mixed-effect model. Publication bias was performed using Egger's linear regression test. Among the items evaluated, blood triglyceride and HDL-cholesterol showed the highest heterogeneity, respectively. Other than blood HDL-cholesterol, total cholesterol, and triglyceride in feces, most items evaluated showed a negative effect size with high significance in the fixed- and random-effect model (p < 0.0001). In the meta-ANOVA and -regression test, administering chitosan and resistant starch was revealed to be most effective in lowering body weight. In addition, chitosan supplementation proved to be an effective solution for serum TNF-α inhibition. In conclusion, chitosan has been shown to be somewhat useful in improving symptoms of lifestyle-related disease. Although there are some limitations in the results of this meta-analysis due to the limited number of animal experiments conducted, chitosan administration nevertheless shows promise in reducing the risk of cholesterol related metabolic disorder.

BACKGROUND: Inflammatory bowel disease (IBD) is a debilitating chronic disease with limited treatment options. Resistant starches may represent a novel treatment for IBD. However, its efficacy and safety remain unclear. Our objective was to perform a systematic review to summarize the preclinical and clinical effects of resistant starch, which may help guide future studies. METHODS: Medline, EMBASE, and the Cochrane Central Register were searched. Included studies investigated the use of resistant starch therapy in in vivo animal models of IBD or human patients with IBD. Articles were screened, and data extracted, independently and in duplicate. The primary outcomes were clinical remission (clinical) and bowel mucosal damage (preclinical). RESULTS: 21 preclinical (n = 989 animals) and seven clinical (n = 164 patients) studies met eligibility. Preclinically, resistant starch was associated with a significant reduction in bowel mucosal damage compared to placebo (standardized mean difference - 1.83, 95% CI - 2.45 to - 1.20). Clinically, five studies reported data on clinical remission but clinical and methodological heterogeneity precluded pooling. In all five, a positive effect was seen in patients who consumed resistant starch supplemented diets. The majority of studies in both the preclinical and clinical settings were at a high or unclear risk of bias due to poor methodological reporting. CONCLUSIONS: Our review demonstrates that resistant starch is associated with reduced histology damage in animal studies, and improvements in clinical remission in IBD patients. These results need to be tempered by the risk of bias of included studies. Rigorously designed preclinical and clinical studies are warranted. Trial registration The review protocols were registered on PROSPERO (preclinical: CRD42019130896; clinical: CRD42019129513).

The effects of resistant starch on glycaemic control are controversial. In this study, a systematic review and meta-analysis of results from nineteen randomised controlled trials (RCT) was performed to illustrate the effects of resistant starch on glycaemic control. A literature search was conducted on PubMed, Scopus and Cochrane electronic databases for related publications from inception to 6 April 2020. Key inclusion criteria were: RCT; resistant starch as intervention substances and reporting glucose- and insulin-related endpoints. Exclusion criteria were: using type I resistant starch or a mixture of resistant starch and other functional food ingredients as intervention; using substances other than digestible starch as controls. The effect of resistant starch on fasting plasma glucose was significant (effect size (ES) -0·09 (95 % CI -0·13, -0·04) mmol/l, P = 0·001) compared with digestible starch. Subgroup analyses revealed that the ES was larger when the dosage of resistant starch was more than 28 g/d (ES -0·16 (95 % CI -0·24, -0·08) mmol/l, P < 0·001) or the intervention period was more than 8 weeks (ES -0·12 (95 % CI -0·18, -0·06) mmol/l, P < 0·001). The effect on homoeostatic model assessment (HOMA)-insulin resistance (IR) was significant (ES -0·33 (95 % CI -0·51, -0·14), P = 0·001). However, the effects on other insulin-related endpoints were not significant, including fasting plasma insulin, four endpoints from the frequently sampled intravenous glucose tolerance test (insulin sensitivity index, acute insulin response, disposition index and glucose effectiveness) and HOMA-β. The current study indicated moderate effects of resistant starch on improving glycaemic control.

Background: Carbohydrate quality and culinary processing can meaningfully alter postprandial glycemia in people with type 1 diabetes (T1D). Cooling gelatinized starch promotes retrogradation and increases resistant starch (RS), potentially attenuating postprandial glucose excursions. Objectives: We investigated whether pasta cooled after cooking (24 h at 4 °C) and reheated before consumption improves postprandial glycemia in adults with T1D without increasing hypoglycemia risk under routine insulin pump bolus-calculator dosing. Methods: In this randomized, single-blind, crossover study, 32 adults with T1D treated with continuous subcutaneous insulin infusion (CSII) consumed two standardized pasta-based meals (50 g of available carbohydrate): freshly cooked pasta and cooled/reheated pasta. Participants administered rapid-acting insulin boluses calculated by their pump bolus calculator 10 min before the meal. Interstitial glucose was recorded for 180 min using flash glucose monitoring. Results: Compared with freshly cooked pasta, cooled/reheated pasta produced lower maximum glycemia (10.7 vs. 12.6 mmol/L, p = 0.0001), lower maximum glycemic rise (2.8 vs. 4.7 mmol/L, p < 0.0001), lower incremental area under the curve (iAUC; 211.9 vs. 524.8 mmol/L × 180 min, p < 0.0001), and a shorter time-to-peak (65 vs. 125 min, p = 0.014). Resistant starch content increased after cooling (12.88 ± 0.06 vs. 8.03 ± 0.08 g/100 g). The number of hypoglycemic episodes did not differ between conditions. Conclusions: Cooling and reheating pasta therefore increased RS and attenuated postprandial glycemia in adults with T1D without increasing early postprandial hypoglycemia in the studied setting.

Objectives: This study aimed to investigate the possible association among texture, oral processing and starch digestive characteristics of hard-cooked (HP) and soft-cooked (SP) potato samples, as well as their acute postprandial glycemic and insulinemic response, when co-ingested with rice in a meal. Methods: HP and SP replaced one-third of rice carbohydrates. Postprandial glycemic and insulinemic responses were measured after test meal ingestion. In vitro experiments evaluated sample physicochemical properties. Results: HP retained more resistant starch (RS) and total phenolics than SP. When co-ingested with rice (HP + R), HP elicited more total chews, higher oral sensory exposure time, slower chewing frequency and longer eating duration. HP + R significantly reduced postprandial glucose iAUC, peak glucose and glycemic excursion. SP + R increased glycemic variability despite reduced iAUCglucose. HP + R also lowered iAUCinsulin, peak insulin and insulin resistance index. The hypoglycemic effect did not extend to the second meal, though composite iAUCglucose over 540 min was reduced. Conclusions: Partially substituting rice with hard-cooked potatoes may help stabilize postprandial glycemic and insulinemic responses, an effect largely attributable to RS retention.

High-amylose maize starch (HAMS), containing fermentable resistant starch (RS), is suggested to improve fluid absorption/retention in athletes but lacks supporting evidence and may increase gastrointestinal symptom (GIS) risk. This study investigated the use of HAMS in pre- and postexercise hydration protocols on hydration status and GIS before, during, and after exertional heat stress (EHS), and thermophysiological strain and exhaustive exercise performance during EHS. Ten endurance-trained runners (eight men and two women) completed two trials in randomized order, consuming a HAMS beverage (12.7 g RS) or placebo 12 hr pre-EHS as part of a 25-ml/kg hyperhydration protocol. Participants then completed 2 hr of steady-state running (60% maximum oxygen uptake, ∼30 °C, 35% relative humidity) followed by a time-to-exhaustion performance test. Post-EHS, participants consumed a HAMS recovery beverage (6.2 g RS) or placebo while replacing 150% of their fluid deficit over 3 hr. HAMS did not influence net fluid balance pre-EHS (HAMS: +44 ± 642 ml, placebo: +210 ± 697 ml) or post-EHS (HAMS: +1,636 ± 687 ml, placebo: +1,662 ± 697 ml; p = .40). Changes in plasma volume and osmolality, and thermophysiological variables, did not differ between trials (all p > .05). Time-to-exhaustion performance test was unaffected by the intervention (HAMS: 1,190 ± 508 s, placebo: 1,343 ± 631 s; p = .10). GIS incidence and severity scores were similar in both trials (all p > .05). A beverage containing RS from HAMS 12 hr before EHS, or immediately following EHS, does not alter retention of water volumes recommended for preexercise hyperhydration or postexercise rehydration nor GIS pre-, during, or post-EHS. As a result, no changes in hydration status, thermophysiological strain, or performance were observed.

Alterations in the gut microbiome and a "leaky" gut are associated with Parkinson's disease (PD), which implies the prospect of rebalancing via dietary intervention. Here, we investigate the impact of a diet rich in resistant starch on the gut microbiome through a multi-omics approach. We conducted a randomized, controlled trial with short-term and long-term phases involving 74 PD patients of three groups: conventional diet, supplementation with resistant starch, and high-fibre diet. Our findings reveal associations between dietary patterns and changes in the gut microbiome's taxonomic composition, functional potential, metabolic activity, and host inflammatory proteome response. Resistant starch supplementation led to an increase in Faecalibacterium species and short-chain fatty acids alongside a reduction in opportunistic pathogens. Long-term supplementation also increased blood APOA4 and HSPA5 and reduced symptoms of PD. Our study highlights the potential of dietary interventions to modulate the gut microbiome and improve the quality of life for PD patients.

Background/Objectives: Resistant starch intake has been shown to influence gut microbiota composition and affect metabolic markers. These effects may be partially attributed to enhanced short-chain fatty acid (SCFA)-mediated energy harvesting and hepatic lipogenesis induced by resistant starch fermentation. However, there is a lack of prospective research addressing these associations. To address this gap, we performed a double-blind, randomized dietary intervention study to investigate the impact of high versus low resistant starch consumption on metabolic markers and gut microbiota among adult women presenting with risk factors for metabolic syndrome. Methods: A total of 30 participants were randomly assigned to either the low-resistant starch (LRS) or high-resistant starch (HRS) diet groups. Each group, comprising 15 participants, consumed one food product per day enriched with either high or low resistant starch for 8 weeks. Changes in metabolic indices and gut microbiota were assessed and compared with baseline values, as assessed before diet (Week 0). Results: After 8 weeks of intervention, the HRS diet significantly increased body weight, body fat, and triglyceride (TG) level (mean change ≈ +40 mg/dL), while reducing blood pressure. Analysis of intestinal microbiota in the HRS group revealed a statistically significant increase in the genus Veillonella following the intervention. Conversely, the genus Marvinbryantia increased significantly in the LRS group. Conclusions: In women with metabolic risk factors, resistant starch supplementation elicited mixed metabolic responses-showing a modest reduction in blood pressure but concurrent increases in adiposity and TG concentrations. As the TG elevation reached a clinically meaningful magnitude, dietary interventions involving high-resistant starch should incorporate regular lipid monitoring to ensure cardiometabolic safety. Collectively, these findings highlight the complex interplay between SCFA-producing gut microbiota and host energy metabolism, suggesting that individualized dietary strategies may be required to optimize metabolic outcomes.

Oat-based foods are widely recommended for dysphagia management and glycemic control, yet the impact of roasting conditions on their health benefits remains unclear. This study compared the postprandial glycemic and insulinemic responses to oat pastes prepared from low-temperature (90-110 °C) and conventional high-temperature (160 °C) roasted oat flours, using refined rice (R) as a reference, in a randomized crossover trial involving 21 healthy young female adults. All oat pastes complied with Level 3 dysphagia safety standards as defined by the International Dysphagia Diet Standardisation Initiative (IDDSI). Results showed that low-temperature roasted oats (L0 and L40) elicited significantly lower postprandial glucose responses than high-temperature roasted oats (H30) and R did, while H30 induced comparable glycemic but higher insulinemic responses than R did. Notably, H30 exhibited impaired insulin sensitivity (higher HOMA-PP) and adverse second-meal effects, likely due to acrylamide formation (507.4 μg/kg) and reduced slowly digestible starch (SDS). In contrast, low-temperature roasting preserved β-glucan integrity, enhanced SDS and resistant starch (RS) content, and improved textural properties without detectable acrylamide. These results demonstrate that optimizing roasting temperatures can mitigate adverse metabolic effects while maintaining swallowing safety, offering critical insights for developing functional foods for elderly and dysphagic populations with specific glycemic management needs.

Our randomized, placebo-controlled trial showed resistant starch (RS), a type of prebiotic, has therapeutic effects in metabolic dysfunction-associated steatotic liver disease (MASLD). Here, we observed its heterogeneous efficacy, where 30% of participants exhibited limited benefits, which was replicated in a multi-center trial (ChiCTR2300074588). Multi-omics analysis and fecal microbiota transplantation identified baseline microbiota as a dominant contributor of response. Further population stratification and network analysis combined with in vitro and in vivo experiments revealed Prevotella as the key cause of low response by inhibiting RS-degrading bacteria, thereby impairing RS utilization. Conversely, Bifidobacterium pseudocatenulatum RRP01, a strain isolated from our cohort, restored RS degradation and improved Prevotella-attenuated RS response. Furthermore, we developed a predictive model integrating baseline microbial and clinical features (area under the curve [AUC] = 0.74-0.87), enabling stratification for personalized interventions. Our study indicates that gut microbiota determines the heterogeneity in RS efficacy and offers possibilities for novel microbiota-oriented precision therapeutics for MASLD.

The intestinal microbiota is shaped by fiber-rich ingredients, such as unripe banana flour (UBF), high in resistant starch (RS). We investigated the effects of RS-rich UBF and inulin on gut microbiota and intestinal function in a double-blind, randomized, placebo-controlled pilot trial. Forty-eight healthy adults consumed maltodextrin (control), inulin, or UBF three times weekly for six weeks. Microbiota composition and function were analyzed using 16S rRNA gene sequencing and PICRUSt, alongside fecal short-chain fatty acids, blood biochemistry, and gastrointestinal parameters. We observed two microbiota clusters at baseline, one Prevotella-rich (P) and one Bacteroides-rich (B), with distinct responses to the interventions. Only cluster P subjects consuming UBF showed significant global microbiota shifts (weighted Unifrac Beta diversity, PERMANOVA p = 0.007) and major functional changes (533 KEGG orthologs, FDR < 0.05). Inulin produced modest modulation (19 KOs) on cluster P, and no effects were observed on cluster B. RS-rich UBF modulated gut microbiota in a composition-dependent manner, supporting the potential of microbiota-based stratification to improve dietary fiber interventions. © 2025. The Author(s).

Describing the epidemiology of colorectal cancer (CRC), Burkitt (1971) emphasised the increased incidence among developed, industrial populations consuming a more refined diet and proposed dietary fibre as the key to the lower CRC incidence noted in underdeveloped countries with less refined diets. Noting the increased incidence of CRC among Alaska Native (AN) peoples and seemingly low presence of fibre in some AN diets, investigators with the University of Pittsburgh and the Alaska Native Tribal Health Consortium proposed to test whether large amounts of fibre contained in a dietary supplement could lower CRC risk. We describe supplement tolerance as reported by AN participants completing a 4-week supplementation trial, which added 44.5 grams per day (g/d) total fibre (23.7 g/d resistant starch (RS)) to the diet of those assigned to the intervention arm and 1 g/d total fibre to those assigned to the control arm. Tolerance of the high fibre supplement would play a key role in protocol adherence as well as any recommendations for future use by the broader population. In this study, the daily RS intervention containing 44.5 g/d additional dietary fibre produced more flatulence than usual but fewer other symptoms were consistently reported compared to the digestible starch (DS) control.

OBJECTIVE: To evaluate the sensorial acceptance of sorghum beverage and its acute effect on the glycemic and insulin and glucagon-like peptide-1 (GLP-1) responses, food consumption, and subjective appetite and satiety sensations in normoglycemic adults. METHODS: The sorghum flour was characterized, followed by the development of the beverages and sensory analysis with 60 adults. Subsequently, an acute trial was conducted with 14 normoglycemic individuals, where capillary and venous blood were collected at different time points to assess glycemic, insulinemic and satiety responses. Glycemic index of the beverages, food intake, and subjective appetite sensations were also evaluated. The study was registered in the Brazilian Registry of Clinical Trials (register number: RBR-32v2gm5). RESULTS: The germinated and extruded BRS305 whole sorghum flour presented resistant starch, condensed tannins, and phenolic compounds, which promote important antioxidant activity. Among the developed sorghum beverages, the strawberry-flavored was the most well sensorially accepted and, therefore, selected for an acute clinical study. The sorghum beverage increased GLP-1 and decreased the incremental area under the curve of insulin and the feeling of "hunger" by maintaining the glycemic and improving insulin response in the normoglycemic adults relative to the control beverage. The subjective sensations of "satisfaction" and "fullness" and the composite satiety score were higher at all points of time for the sorghum beverage. CONCLUSION: Germinated and extruded sorghum beverage presented good nutritional and sensory quality, and its acute consumption improved postprandial insulin and GLP-1 responses, enhanced satiety in normoglycemic adults.

We previously confirmed that tannic acid could delay the metabolism of resistant starch in vitro, which suggested that tannic acid might deliver resistant starch to the distal colon in vivo. Accordingly, co-supplementation of resistant starch and tannic acid might be beneficial for keeping the distal colon healthy. Thus, this study compared the effects of resistant starch, tannic acid and their mixtures on dextran sulfate sodium (DSS)-induced ulcerative colitis in mice. It was found that the mixtures had a more profound effect on ameliorating DSS-induced ulcerative colitis than resistant starch or tannic acid. In particular, the mixtures reversed the histology damage of the distal colon induced by DSS, while resistant starch or tannic acid alone did not. The mixtures also had a stronger ability to resist oxidative stress and inhibit inflammation in the distal colon. These results suggested that resistant starch and tannic acid synergistically alleviated DSS-induced ulcerative colitis, particularly in the distal colon. On the other hand, DSS decreased the production of short-chain fatty acids and induced significant microbial disorder, while the administration of resistant starch, tannic acid and their mixtures reversed the above shifts caused by DSS. In particular, the mixtures exhibited stronger prebiotic activity, as indicated by the microbial composition and production of short-chain fatty acids. Therefore, it was inferred that tannic acid delivered resistant starch to the distal colon of mice, and thus the mixtures had stronger prebiotic activity. As a result, the mixtures effectively alleviated ulcerative colitis in the whole colon.

This study aimed to investigate the synergistic effect of lotus seed resistant starch (LRS) and short-chain fatty acids (SCFAs) on mice fecal bacterial flora and the contents of SCFAs in vitro. Following 24 h of fermentation, 16S rRNA analysis revealed several differences in the fecal microbiota community structure among primal bacteria (PB), LRS and different SCFAs combined with LRS groups (SCFAs-LRS). The LRS group increased the relative abundance of Lactobacillus, Allobaculum, Clostridium, Bacteroides and Prevotella. Among the SCFAs-LRS group, AA-LRS increased the relative abundance of Prevotella, and Bacillus. PA-LRS increased abundance of Sphingomonas and the BA-LRS group significantly increased the relative abundance of Rhizobiales, Brucellaceae and Ochrobactrum. Meanwhile, propionic acid and BA productions significantly increased in the BA-LRS group. The SCFAs-LRS group elicited a beneficial effect on the fecal microbiota by increasing production of SCFAs. We highlight the fact that the combination of LRS and SCFA can increase the contents of SCFAs produced by mice fecal microbiota. In short, the combination of LRS and SCFA can influence intestinal flora by promoting the growth of beneficial bacteria and can serve as new prebiotics for promoting health and disease management.

Cyclodextrinase (CDase) and cyclodextrin glucosyltransferase (CGTase) were synergistically used to provide a novel enzymatic method in lowing in vitro digestibility of waxy maize starch. The molecular structure, malto-oligosaccharide composition, and digestibility properties of the generated products were investigated. The molecular weight was reduced to 0.3 × 105 g/mol and 0.2 × 105 g/mol by simultaneous and sequential treatment with CDase and CGTase, while the highest proportion of chains with degree of polymerization (DP) < 13 was obtained by simultaneous treatment. The resistant starch contents were increased to 27.5% and 36.9% by simultaneous and sequential treatments respectively. Dual-enzyme treatment significantly promoted the content of malto-oligosaccharides (MOSs) by hydrolyzing cyclodextrins from CGTase with CDase. However, the replacement of cyclodextrins by MOSs did not obviously influence the digestibility of the products. The starch digestion kinetics further revealed the hydrolysis pattern of these two enzymes on the starch hydrolysate. It was proved that the starch digestibility could be lowered by modulating the molecular structure and beneficial MOSs content by this dual-enzyme treatment.

SCOPE: Antibiotics ampicillin 1 g/L and neomycin 0.5 g/L were added to drinking water before or during feeding of resistant starch (RS) to rats to inhibit fermentation. METHODS AND RESULTS: In a preliminary study, antibiotics and no RS were given prior to rats receiving a transplant of cecal contents via gavage from donor rats fed RS (without antibiotics) or a water gavage before feeding resistant starch to both groups. Antibiotics given prior to feeding RS did not prevent later fermentation of RS regardless of either type of gavage. In the second study, antibiotics were given simultaneously with feeding of RS. This resulted in inhibition of fermentation of RS with cecal contents pH >8 and low amounts of acetate and butyrate. Rats treated with antibiotics had reduced Bifidobacteria spp., but similar Bacteroides spp. to control groups to reduce acetate and butyrate and preserve the production of propionate. Despite reduced fermentation, rats given antibiotics had increased glucagon-like peptide 1 (GLP-1) and cecum size, measures that are usually associated with fermentation. CONCLUSIONS: A simultaneous delivery of antibiotics inhibited fermentation of RS. However, increased GLP-1 and cecum size would be confounding effects in assessing the mechanism for beneficial effects of dietary RS by knocking out fermentation. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

High-amylose maize starch (HAM) is a common source material to make resistant starch with its high content of amylose (>70%). In the current investigation, the self-assembly of amylose in the presence of bioactive tea polyphenols (TPLs) and resulting slow digestion property of starch were explored. The experimental results using a mouse model showed a slow digestion property can be achieved with an extended and moderate glycemic response to HAM starch cocooked with TPLs. Further studies using a dilute aqueous amylose solution (0.1%, w/v) revealed an increased hydrodynamic radius of amylose molecules, indicating that TPLs could bridge them together, leading to increased molecular sizes. On the other hand, the bound TPLs interrupted the normal process of amylose recrystallizaiton evidenced by a decreased viscosity and storage modulus (G') of HAM (5%) gel, a rough surface of the cross-section of HAM film, and decreased short-range orders examined by Fourier transform infrared spectral analysis. Single-step degradation curves in the thermal gravimetric profile demonstrated the existence of a self-assembled amylose-TPL complex, which is mainly formed through hydrogen bonding interaction according to the results of iodine binding and X-ray powder diffraction analysis. Collectively, the amylose-TPL complexation influences the normal self-assembling process of amylose, leading to a low-ordered crystalline structure, which is the basis for TPLs' function in modulating the digestion property of HAM starch to produce a slowly digestible starch material that is beneficial to postprandial glycemic control and related health effects.

waxy/amylose-extender (wx/ae) double-mutant japonica rice (Oryza sativa L.) produces resistant starch (RS) and a large amount of γ-oryzanol. Our previous study has shown the hypolipidemic effect of wx/ae brown rice on mice. To identify the functional constituents of the hypolipidemic activity in wx/ae rice, we prepared pure wx/ae starch and γ-oryzanol from wx/ae rice and investigated their effect on the lipid metabolism in BALB/c.KOR/Stm Slc-Apoe(shl) mice. The mice were fed for 3 weeks a diet containing non-mutant rice starch, non-mutant rice starch plus γ-oryzanol, wx/ae starch, or wx/ae starch plus γ-oryzanol. γ-Oryzanol by itself had no effect on the lipid metabolism, and wx/ae starch prevented an accumulation of triacylglycerol (TAG) in the liver. Interestingly, the combination of wx/ae starch plus γ-oryzanol not only prevented a TAG accumulation in the liver, but also partially suppressed the rise in plasma TAG concentration, indicating that wx/ae starch and γ-oryzanol could have a synergistic effect on the lipid metabolism.

Dietary products are among the therapeutic approaches used to modify intestinal microflora and to promote protective effects during the intestinal inflammatory process. Because the banana plant is rich in resistant starch, which is used by colonic microbiota for the anaerobic production of the short-chain fatty acids that serve as a major fuel source for colonocytes: first, green dwarf banana flour produces protective effects on the intestinal inflammation acting as a prebiotic and, second, combination of this dietary supplementation with prednisolone presents synergistic effects. For this, we used the trinitrobenzenesulphonic acid (TNBS) model of rat colitis. Our results revealed that the protective effect produced by a combination of 10% green dwarf banana flour with prednisolone was more pronounced than those promoted by a single administration of prednisolone or a diet containing 10% or 20% banana flour. This beneficial effect was associated with an improvement in the colonic oxidative status because the banana flour diet prevented the glutathione depletion and inhibited myeloperoxidase activity and lipid peroxidation. In addition, the intestinal anti-inflammatory activity was associated with an inhibition of alkaline phosphatase activity, a reduction in macroscopic and microscopic scores, and an extension of the lesions. In conclusion, the dietary use of the green dwarf banana flour constitutes an important dietary supplement and complementary medicine product to prevention and treatment of human inflammatory bowel disease.

Daidzein is metabolized to equol in the gastrointestinal tract by gut microflora. Equol has greater estrogenic activity than genistein and daidzein, with its production shown to be promoted by dietary fiber. It is known that resistant starch (RS) is not absorbed in the proximal intestine and acts as dietary fiber in the colon. In this study, we investigated the combined effects of daidzein and RS intake on equol production, bone mineral density, and intestinal microflora in ovariectomized (OVX) mice. Female mice of the ddY strain, aged 8 weeks, were either sham operated (n = 6) or OVX. The OVX mice were randomly divided into 5 groups: OVX control (n = 6), OVX fed 0.1% daidzein-supplemented diet (OVX + Dz, n = 8), OVX fed 0.1% daidzein- and 12% RS-supplemented diet (OVX + Dz + RS, n = 8), OVX fed 12% RS-supplemented diet (OVX + RS, n = 8), and OVX who received daily subcutaneous administration of 17 β-estradiol (n = 6). After 6 weeks, urinary equol concentration was significantly higher in the OVX + Dz + RS group than in the OVX + Dz group. The bone mineral density of the whole tibia was higher in the OVX + Dz +RS group compared with the OVX + Dz group. The occupation ratios of Bifidobacterium spp in the cecal microflora in groups fed RS were significantly higher than those in the other groups. The present study demonstrated that RS may increase the bioavailability of daidzein.

Erratum in Br J Nutr. 2009 Jun;101(12):1885. Dietary non-digestible carbohydrates (NDC) play an important role in large-bowel health and one form of NDC, resistant starch (RS), can promote low levels of DNA damage and other markers of colonic health. The objective of the present study was to determine whether the ability of dietary RS or other NDC to influence colonic health, particularly DNA damage, is dependent on the type of dietary oil. We compared the effects of diets containing 10 % of NDC from cellulose, wheat bran, high-amylose maize starch (HAS, a rich source of RS type 2) or a retrograded HAS (RHAS, a rich source of RS type 3) on DNA damage, SCFA production and bacterial changes in the large bowel of rats. Each carbohydrate source was combined with 10 % fish oil (FO) or Sunola oil (SO; rich in oleic acid). There was a significant interaction between NDC and oil treatments on single-strand DNA breaks in colonocytes isolated from the colon. The damage in rats consuming RHAS was greater for FO consumption than for SO consumption. There was a significant interaction between NDC and oils on caecum weights and treatment effects of NDC and oils were observed for the weights and lengths of other gut tissues. Significant differences were found in colonic SCFA pools and caecal numbers of lactobacilli, bifidobacteria, Escherichia coli and Bacteroides fragilis with the various NDC and oil treatments. The present results demonstrate that the effects of NDC and oils, particularly on colonic DNA damage, can depend on how they are combined within the diet.

Epidemiological, clinical, animal and laboratory studies have all provided evidence for the protective effects of non-steroidal anti-inflammatory drugs (NSAIDs), such as aspirin, against colorectal cancer. The main established target for NSAID action is cyclooxygenase (COX) and the inducible isoform, COX-2, is up-regulated in colorectal cancer. Rat intestinal epithelial cells transfected with a COX-2 expression vector have previously been found to be resistant to butyrate-induced apoptosis. Butyrate, a by-product of dietary fibre fermentation, is known to induce differentiation and apoptosis in colorectal tumour cells in vitro. In recent years there has been considerable interest in the possible role of dietary fibre/resistant starch in the prevention of colorectal cancer. In this study we investigated whether inhibition of COX-2 with a highly selective COX-2 inhibitor (NS-398) would sensitize human colorectal carcinoma cells to the growth inhibitory effect of butyrate. HT29 and S/KS colorectal carcinoma cell lines were treated for 72 h with 2 mM butyrate and/or 10 microM NS-398. Addition of 10 microM NS-398 alone (to inhibit COX-2 activity) did not result in detectable growth inhibition in either of the cell lines. NS-398 enhanced sensitivity to the growth inhibitory effect of butyrate in HT29 cells expressing COX-2 protein. In contrast, NS-398 did not sensitize S/KS cells lacking detectable COX-2 protein and function (as determined by prostaglandin E(2) production) to the growth inhibitory effect of butyrate. In addition, we report that butyrate treatment of carcinoma (HT29) and adenoma (PC/AA/C1) cells leads to up-regulation of COX-2 protein. Thus NS-398 only appears to sensitize human colorectal carcinoma cells expressing COX-2 protein to the growth inhibitory effect of butyrate. As COX-2 is up-regulated in colorectal carcinogenesis, this could have important implications for the selective inhibition of cells expressing COX-2 protein over those lacking COX-2 protein expression and for dietary modification to be considered alongside NSAIDs in the prevention, and possibly treatment, of colorectal cancer.