Long-term cholesterol-lowering effects of psyllium as an adjunct to diet therapy in the treatment of hypercholesterolemia

Plantago consumption significantly reduces total cholesterol and low-density lipoprotein cholesterol in adults: A systematic review and meta-analysis

Plantago is rich in soluble fiber, known for its beneficial health effects. Given this, we hypothesized that Plantago consumption might positively influence blood lipid in adults. Researchers have conducted numerous randomized controlled trials (RCTs), revealing the impacts of Plantago consumption on various blood lipid parameters. However, findings regarding specific blood lipid parameters have shown variability. This study aimed to comprehensively assess the effect of Plantago consumption on blood lipid parameters. Eligible studies evaluating the effects of Plantago consumption on blood lipid were searched in 5 electronic databases published up to August 2023. Analysis used a random effects model to determine weighted mean difference and 95% confidence intervals. In total, 29 RCTs including 2769 participants were included. Compared with the control group, Plantago consumption significantly reduced total cholesterol (TC) by 0.28 mmol/L and low-density lipoprotein cholesterol (LDL-C) by 0.35 mmol/L, correlating to an estimated 7% decrease in cardiovascular event risk. Conversely, no substantial effects were observed on high-density lipoprotein cholesterol or triglycerides. Subgroup analyses of 29 RCTs revealed that TC concentrations were significantly lowered in studies that included male participants, those who were healthy, or had lipid disorders. Additionally, TC and LDL-C were significantly lower in participants consuming Plantago husk or psyllium, and soluble fiber intake was specifically effective in lowering TC, LDL-C, and triglycerides. In conclusion, Plantago consumption can significantly lower TC and LDL-C concentrations. The findings will provide crucial insights into the potential of Plantago in dietary strategies for blood lipid management.

Dietary fibre definition revisited - The case of low molecular weight carbohydrates

Low molecular weight (LMW) non-digestible carbohydrates (namely, oligosaccharides and inulin) are accepted as dietary fibre in many countries worldwide. The inclusion of oligosaccharides as dietary fibre was made optional within the Codex Alimentarius definition in 2009, which has caused great controversy. Inulin is accepted as dietary fibre by default, due to being a non-digestible carbohydrate polymer. Oligosaccharides and inulin occur naturally in numerous foods and are frequently incorporated into commonly consumed food products for a variety of purposes, such as to increase dietary fibre content. LMW non-digestible carbohydrates, due to their rapid fermentation in the proximal colon, may cause deleterious effects in individuals with functional bowel disorders (FBDs) and, as such, are excluded on the low FODMAP (fermentable oligosaccharides, disaccharides, and polyols) diet and similar protocols. Their addition to food products as dietary fibre allows the use of associated nutrition/health claims, causing a paradox for those with FBDs, which is further complicated by lack of clarity on food labelling. Therefore, this review aimed to discuss whether the inclusion of LMW non-digestible carbohydrates within the Codex definition of dietary fibre is warranted. This review provides justification for the exclusion of oligosaccharides and inulin from the Codex definition of dietary fibre. LMW non-digestible carbohydrates could, instead, be placed in their own category as prebiotics, recognised for their specific functional properties, or considered food additives, whereby they are not promoted for being beneficial for health. This would preserve the concept of dietary fibre being a universally beneficial dietary component for all individuals.

Are all fibres created equal with respect to lipid lowering? Comparing the effect of viscous dietary fibre to non-viscous fibre from cereal sources: a systematic review and meta-analysis of randomised controlled trials

Although compelling evidence from observational studies supports a positive association between consumption of cereal fibre and CVD risk reduction, randomised controlled trials (RCT) often target viscous fibre type as the prospective contributor to lipid lowering to reduce CVD risk. The objective of our study is to compare the lipids-lowering effects of viscous dietary fibre to non-viscous, cereal-type fibre in clinical studies. RCT that evaluated the effect of viscous dietary fibre compared with non-viscous, cereal fibre on LDL cholesterol and alternative lipid markers, with a duration of ≥ 3 weeks, in adults with or without hypercholesterolaemia were included. Medline, EMBASE, CINAHL and the Cochrane Central Register were searched through October 19, 2021. Data were extracted and assessed by two independent reviewers. The generic inverse variance method with random effects model was utilised to pool the data which were expressed as mean differences (MD) with 95 % CI. Eighty-nine trials met eligibility criteria (n 4755). MD for the effect of viscous dietary fibre compared with non-viscous cereal fibre were LDL cholesterol (MD = -0·26 mmol/l; 95 % CI: -0·30, -0·22 mmol/l; P < 0·01), non-HDL cholesterol (MD = -0·33 mmol/l; 95 % CI: -0·39, -0·28 mmol/l; P < 0·01) and Apo-B (MD = -0·04 g/l; 95 % CI: -0·06, -0·03 g/l; P < 0·01). Viscous dietary fibre reduces LDL cholesterol and alternative lipid markers relative to the fibre from cereal sources, hence may be a preferred type of fibre-based dietary intervention targeting CVD risk reduction.

Effects of Laser Irradiation at 488, 514, 532, 552, 660, and 785 nm on the Aqueous Extracts of Plantago lanceolata L.: A Comparison on Chemical Content, Antioxidant Activity and Caco-2 Viability

In this study, six laser radiation (488 nm/40 mW, 514 nm/15 mW, 532 nm/20 mW, 552 nm/15 mW, 660 nm/ 75 mW, and at 785 nm/70 mW) were tested on the aqueous extracts of leaves of Plantago lanceolata L. to compare extraction efficacy and antioxidant and cell viability effects in vitro. Briefly, in comparison with the control extract, laser extracts at 488, 514, 532, and 552 nm revealed small acquisitions of total extractible compounds in samples (up to 6.52%; laser extracts at 488 and 532 nm also revealed minerals and micro-elements increases (up to 6.49%); the most prominent results were obtained upon Fe (up to 38%, 488 nm), Cr (up to 307%, 660 nm), and Zn (up to 465%, 532 nm). Laser extracts at 488, 514, 552, and 785 nm proved more intense antioxidant capacity than the control sample, while laser extract at 660 nm indicated clear pro-oxidant effects. Caco-2 cells study indicated stimulatory activity for the extracts at 488 nm, no effects at 532 nm, and the decrease of the cell viability in the case of extracts at 660 nm respectively. Further studies are necessary to understand the pro-oxidant effects observed in the case of extracts exposed to laser radiation at 660 nm.

Amelioration of Obesity in Mice Fed a High-Fat Diet with Uronic Acid–Rich Polysaccharides Derived from Tremella fuciformis

Obesity is rapidly becoming an emerging disease in developing countries due to the Westernization of societies and lifestyle changes. This study evaluated the ameliorative effect of acidic heteropolysaccharides derived from Tremella fuciformis (TFPS) on high-fat diet (HFD; 34.9% fat)-induced obesity in mice. The TFPS exhibited high uronic acid content and high viscosity in water. The structural characteristics of TFPS showed that average molecular weight was 679 kDa, and the monosaccharide composition was galactose, glucose, fructose, xylose, fucose, and mannose at a ratio of 1.0:6.5:10.0:18.5:30.5:67.5. In an in vivo study, HFD-induced obese C57BL/6 mice were orally given a TFPS treatment at 1 and 2 g/kg of body weight for 8 weeks. The TFPS treatment significantly reduced features of obesity in the mice, namely weight gain, feed efficiency, body fat percentage, and serum cholesterol level and increased fecal lipid content, compared with mice fed an HFD with water. In addition, TFPS exhibited the inhibition of cholesterol micelles in vitro in a concentration-dependent manner. In conclusion, the TFPS treatment ameliorated the diet-induced obesity in the mice, presumably reducing fat absorption in the intestine by interfering with viscous TFPS.

A Preliminary Study on the Effect of Psyllium Husk Ethanolic Extract on Hyperlipidemia, Hyperglycemia, and Oxidative Stress Induced by Triton X-100 Injection in Rats

The aim of this study is to assess the efficiency of psyllium husk ethanolic extract (PHEE) on Triton X-100 induced hyperlipidemic rats by studying the changes in hepatic and pancreatic function and histopathology. Forty male albino rats (bodyweight 175-188 g) were grouped randomly into four sets with ten rats. The experimental groups included: (1) control group (CON); (2) Triton X-100 induced hyperlipidemic group-rats were intraperitoneally injected with a single dose of Triton X-100 (100 mg/kg body weight) on the 21st day of Trial onset; (3) PHEE group-PHEE was orally administered (100 mg/kg body weight dissolved in 1 mL of distilled water) by gastric tube from the first day of the experiment until the fortieth day, once daily, (PHEE); (4) PHEE +Triton group, which received PHEE orally with the induction of hyperlipidemia. Treating hyperlipidemic rats with PHEE showed a decrease in the total serum lipids, triglyceride (TG), total cholesterol (TC), atherogenic index (AI), and malondialdehyde (MDA) with an increase in superoxide dismutase (SOD) and catalase (CAT) activities. PHEE administration alleviated the negative impact of Triton on the serum levels of glucose, insulin, glycated hemoglobin (HbA1c), homeostatic model assessment for insulin resistance (HOMA IR index), leptin hormone, Alanine Aminotransferase (ALT), Aspartate Aminotransferase (AST), Gamma-Glutamyl Transferase (GGT) and proteinogram. The Triton-induced hyperlipidemic rats showed extensive histopathological changes in the liver and pancreas, which were alleviated with PHEE administration. It could be concluded that PHEE has potent effects against hyperlipidemia, hyperglycemia, and oxidative stress due to its biologically active constituents detected by GC-MS analysis. This study's findings may help develop a novel trial against the effects of hyperlipidemia in the future.

Relationship between dietary carbohydrate quality index and metabolic syndrome among type 2 diabetes mellitus subjects: a case-control study from Ghana

BACKGROUND

Dietary carbohydrate quality may play an important role in disease development. We evaluated the association between carbohydrate quality index (CQI) and the odds of metabolic syndrome (MetS) in type 2 diabetes mellitus (T2DM) subjects in Ghana.

METHODS

In this case-control study, we analyzed data using 124 T2DM subjects. We obtained dietary information using 2-day 24-h dietary recalls. We calculated CQI from dietary fiber, glycemic index, whole grains/total grains ratio, and solid carbohydrates/total carbohydrates ratio. Serum lipid profiles were measured after an overnight fast of 8-12 h.

RESULTS

Upon adjustments for the effects of covariates, the CQI showed a positive association with high-density lipoprotein cholesterol concentration (beta coefficient (β) = 0.24; standard error (SE) = 0.20; P for trend = 0.01), and an inverse relationship with waist circumference (β = - 17.29; SE = 4.00; P for trend < 0.001), systolic blood pressure (β = - 15.74; SE = 4.69; P for trend < 0.001), diastolic blood pressure (β = - 7.23; SE = 2.97; P for trend = 0.02), and triglyceride concentrations (β = - 0.43; SE = 0.11; P for trend < 0.001). Overall, the CQI had an inverse relationship with the odds of MetS (Odds ratio _{tertile 3 vs.1} 0.05; 95% Confidence interval: 0.01-0.23; p-trend < 0.001). Also, a positive correlation was found between the CQI and fiber, but the CQI showed a negative relationship with dietary glycemic index.

CONCLUSIONS

The present results suggest an inverse association between the CQI of a diet and the odds of MetS. The CQI approach of dietary recommendation may be a useful strategy for dietary carbohydrate selection for the prevention of MetS.

Psyllium husk intake and risk of type 2 diabetes: an evidence-based scientific and regulatory review of a qualified health claim conducted by the US Food and Drug Administration

The US Food and Drug Administration (FDA) received a petition from a company requesting that FDA issue an authorized health claim for the relationship between psyllium husk and a reduced risk of type 2 diabetes. After an initial assessment of the available scientific evidence, FDA determined that significant scientific agreement was lacking for this substance-disease relationship, whereupon the company agreed to have its petition reviewed as a qualified health claim. This article describes the process FDA used in conducting an evidence-based review of the science underpinning the proposed claim and addresses certain safety issues associated with psyllium husk that FDA considered in its review of the petition. Of the 6 studies from which scientific conclusions could be drawn, as identified through FDA's review, psyllium husk significantly improved plasma glucose levels and insulin sensitivity in only 1 study. Therefore, FDA's enforcement discretion letter for this qualified health claim stated: "Psyllium husk may reduce the risk of type 2 diabetes, although the FDA has concluded that there is very little scientific evidence for this claim."

Dietary solutions to dyslipidemia: Milk protein-polysaccharide conjugates as liver biochemical enhancers

Protein-polysaccharide interactions have been a focus of scientific attention. This study aimed to improve the antioxidant and hepatoprotective effects of buffalo total milk proteins and whey protein hydrolysate (WPH) through noncovalent interactions with Psyllium husk (ispaghula) mucilage (PHM) and Nabq mucilage (NabM). Chemical composition, phenolic content, and antioxidant activities of milk protein-mucilage complexes were explored. The effects of resulting complexes on liver function, hyperlipidemia, and histopathology of the liver in rats fed high-fat diet (HFD) were investigated. The results showed that the complexes exerted significant effect on normalizing tested parameters; WPH-NabM had the most significantly decreased level of malondialdehyde content and the liver histopathological examination proved an improvement in all groups fed with these complexes. These complexes can be used as functional protection elements against the nonalcoholic fatty liver disease. PRACTICAL APPLICATIONS: PHM, NabM, and their complexes with milk proteins were proved to improve liver function, enhancing most of its measurable parameters and also diminishing the risk of cardiovascular disease. Mice with HFD achieved better health circumstances by combining these ingredients in their diet. Knowing how much these diseases proliferate in the western world and its correlation with high-fat consumption and modern lifestyle, its conjugation with PHM/NabM-MP complexes may reduce the negative impact of unhealthy food intake and, on some parameters, even improving the whole liver function. For that reason, the present study supports and pushes forward the dissemination and consumption of ispaghula or Nabq (the polysaccharides sources) or supplements originating from them. Although many interactions concerning milk proteins have already been analyzed, our study also proposes the interaction with bioactive polysaccharides as useful, opening a field of research aimed at the better application of milk proteins.

Medicinal plants in treatment of hypertriglyceridemia: A review based on their mechanisms and effectiveness

BACKGROUND

Hypertriglyceridemia (HTg) defines as high amounts of triglyceride (TG) in the blood which can lead to serious complications over time. HTg is usually a part of metabolic disorders such as diabetes mellitus, metabolic syndrome, and dyslipidemia. Different medications have been used to treat HTg but experimentally, many herbs have been recommended for treating HTg as an adjuvant therapy. In most cases, the recommendations are based on animal studies and limited evidences exist about their mechanisms and clinical usefulness.

PURPOSE

This review focused on the herbs which have been shown TG lowering effect.

METHOD

The search was done in PubMed, Science Direct, Scopus, Web of Science and Google Scholar databases a 20-year period between 1997 to 2017 with keywords search of medicinal plant, plant extract, hypertriglyceridemia, dyslipidemia, hyperlipidemia, lipoprotein lipase and apolipoprotein.

RESULTS

According to the results, many plants showed positive effects but Allium sativum, Nigella sativa, Curcuma longa, Anethum graveolens and Commiphora mukul had the best TG lowering effect with exact mechanisms of action.

CONCLUSION

It seems that use of these plants as complementary therapeutics or extraction of their active ingredients along with currently available drugs will improve the management of HTg in patients.

Effect of psyllium (Plantago ovata) fiber on LDL cholesterol and alternative lipid targets, non-HDL cholesterol and apolipoprotein B: a systematic review and meta-analysis of randomized controlled trials

Background

Studies have identified viscous dietary fiber as potentially attenuating cholesterol, including psyllium, which reduces LDL cholesterol and thus may complement cardiovascular disease (CVD) treatment.

Objectives

The aims of this study were to update evidence on the effect of psyllium on LDL cholesterol and to provide an assessment of its impact on alternate markers: non-HDL cholesterol and apolipoprotein B (apoB).

Design

Medline, EMBASE, CINAHL, and the Cochrane Central Register of Controlled Trials were searched through 3 October 2017. Independent reviewers extracted relevant data and assessed risk of bias. We included randomized controlled trials with a duration of ≥3 wk that assessed the effect of psyllium on blood lipids in individuals with or without hypercholesterolemia. Data were pooled by using the generic inverse variance method with random-effects models and expressed as mean differences (MDs) with 95% CIs. Heterogeneity was assessed by Cochran's Q statistic and quantified by the I2 statistic. Overall quality of the evidence was assessed by using the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) approach.

Results

We included 28 trials in our analysis (n = 1924). Supplementation of a median dose of ∼10.2 g psyllium significantly reduced LDL cholesterol (MD = -0.33 mmol/L; 95% CI: -0.38, -0.27 mmol/L; P < 0.00001), non-HDL cholesterol (MD = -0.39 mmol/L; 95% CI: -0.50, -0.27 mmol/L; P < 0.00001), and apoB (MD = -0.05 g/L; 95% CI: -0.08, -0.03 g/L; P < 0.0001). Effect estimates for LDL cholesterol and non-HDL cholesterol were graded as moderate quality on the basis of downgrades for inconsistency and graded as high quality for apoB.

Conclusion

Psyllium fiber effectively improves conventional and alternative lipids markers, potentially delaying the process of atherosclerosis-associated CVD risk in those with or without hypercholesterolemia. This trial is registered at www.clinicaltrials.gov as NCT03346733.

A new heteropolysaccharide from the seed husks of Plantago asiatica L. with its thermal and antioxidant properties

A new heteropolysaccharide (PMH) with a molecular weight of 1.4 × 10³ kDa was isolated from the seed husks of Plantago asiatica L. The monosaccharide composition of PMH was determined as glucose, xylose, arabinose, rhamnose, galactose and galacturonic acid with a molar ratio of 1.0 : 1.8 : 2.4 : 3.8 : 4.9 : 8.5. The backbone of PMH consisted of 1,4-β-d-GalpA with the side chains mainly composed of 1,3-α-d-Galp and 1,2-α-d-Galp which were attached to the O-3 of GlapA. The thermal analysis using the Flynn-Wall-Ozawa (FWO) method revealed that PMH had an apparent activation energy (E_a) of 173.1 kJ mol^-1. PMH experienced a major decomposition during the heating process at a temperature of 91.1 °C with a dry weight loss of 31.1%. Moreover, PMH exhibited stronger antioxidant ability than commercial psyllium, partially due to its higher content of uronic acid. The results suggested that PMH could be used in functional foods due to its structural, thermal and antioxidant characteristics.

Marine polysaccharides attenuate metabolic syndrome by fermentation products and altering gut microbiota: An overview

Marine polysaccharides (MPs), including plant, animal, and microbial-derived polysaccharides, can alleviate metabolic syndrome (MetS) by different regulation mechanisms. MPs and their derivatives can attenuate MetS by vary cellular signal pathways, such as peroxisome proliferator-activated receptor, 5' adenosine monophosphate-activated protein kinase, and CCAAT/enhancer binding protein-α. Also, most of MPs cannot be degraded by human innate enzymes, but they can be degraded and fermented by human gut microbiota. The final metabolic products of these polysaccharides are usually short-chain fatty acids (SCFAs), which can change the gut microbiota ecology by altering the existing percentage of special microorganisms. In addition, the SCFAs and changed gut microbiota can regulate enteroendocrine hormone secretion, blood glucose, lipid metabolism levels, and other MetS symptoms. Here, we summarize the up-to-date findings on the effects of MPs, particularly marine microbial-derived polysaccharides, and their metabolites on attenuating MetS.

Food Ingredients That Inhibit Cholesterol Absorption

Cholesterol is a vital component of the human body. It stabilizes cell membranes and is the precursor of bile acids, vitamin D and steroid hormones. However, cholesterol accumulation in the bloodstream (hypercholesterolemia) can cause atherosclerotic plaques within artery walls, leading to heart attacks and strokes. The efficiency of cholesterol absorption in the small intestine is of great interest because human and animal studies have linked cholesterol absorption with plasma concentration of total and low density lipoprotein cholesterol. Cholesterol absorption is highly regulated and influenced by particular compounds in the food supply. Therefore, it is desirable to learn more about natural food components that inhibit cholesterol absorption so that food ingredients and dietary supplements can be developed for consumers who wish to manage their plasma cholesterol levels by non-pharmacological means. Food components thus far identified as inhibitors of cholesterol absorption include phytosterols, soluble fibers, phospholipids, and stearic acid.

Psyllium fiber improves glycemic control proportional to loss of glycemic control: a meta-analysis of data in euglycemic subjects, patients at risk of type 2 diabetes mellitus, and patients being treated for type 2 diabetes mellitus

BACKGROUND

A number of health benefits are associated with intake of soluble, viscous, gel-forming fibers, including reduced serum cholesterol and the attenuation of postprandial glucose excursions.

OBJECTIVE

We assess the effects of psyllium, which is a soluble, gel-forming, nonfermented fiber supplement, on glycemic control in patients who were being treated for type 2 diabetes mellitus (T2DM) and in patients who were at risk of developing T2DM.

DESIGN

A comprehensive search was performed of available published literature (Scopus scientific database) and clinical records stored by Procter & Gamble with the use of key search terms to identify clinical studies that assessed the glycemic effects of psyllium in nondiabetic, pre-T2DM, and T2DM patients.

RESULTS

We identified 35 randomized, controlled, clinical studies that spanned 3 decades and 3 continents. These data were assessed in 8 meta-analyses. In patients with T2DM, multiweek studies (psyllium dosed before meals) showed significant improvement in both the fasting blood glucose (FBG) concentration (-37.0 mg/dL; P < 0.001) and glycated hemoglobin (HbA1c) [-0.97% (-10.6 mmol/mol); P = 0.048]. Glycemic effects were proportional to baseline FBG; no significant glucose lowering was observed in euglycemic subjects, a modest improvement was observed in subjects with pre-T2DM, and the greatest improvement was observed in subjects who were being treated for T2DM.

CONCLUSIONS

These data indicate that psyllium would be an effective addition to a lifestyle-intervention program. The degree of psyllium's glycemic benefit was commensurate with the loss of glycemic control. Because the greatest effect was seen in patients who were being treated for T2DM, additional studies are needed to determine how best to incorporate psyllium into existing prevention and treatment algorithms with concomitant hypoglycemic medications.

Statin-associated muscle symptoms: impact on statin therapy-European Atherosclerosis Society Consensus Panel Statement on Assessment, Aetiology and Management

Statin-associated muscle symptoms (SAMS) are one of the principal reasons for statin non-adherence and/or discontinuation, contributing to adverse cardiovascular outcomes. This European Atherosclerosis Society (EAS) Consensus Panel overviews current understanding of the pathophysiology of statin-associated myopathy, and provides guidance for diagnosis and management of SAMS. Statin-associated myopathy, with significant elevation of serum creatine kinase (CK), is a rare but serious side effect of statins, affecting 1 per 1000 to 1 per 10 000 people on standard statin doses. Statin-associated muscle symptoms cover a broader range of clinical presentations, usually with normal or minimally elevated CK levels, with a prevalence of 7-29% in registries and observational studies. Preclinical studies show that statins decrease mitochondrial function, attenuate energy production, and alter muscle protein degradation, thereby providing a potential link between statins and muscle symptoms; controlled mechanistic and genetic studies in humans are necessary to further understanding. The Panel proposes to identify SAMS by symptoms typical of statin myalgia (i.e. muscle pain or aching) and their temporal association with discontinuation and response to repetitive statin re-challenge. In people with SAMS, the Panel recommends the use of a maximally tolerated statin dose combined with non-statin lipid-lowering therapies to attain recommended low-density lipoprotein cholesterol targets. The Panel recommends a structured work-up to identify individuals with clinically relevant SAMS generally to at least three different statins, so that they can be offered therapeutic regimens to satisfactorily address their cardiovascular risk. Further research into the underlying pathophysiological mechanisms may offer future therapeutic potential.

[Dietary fiber--adequate intake and effects on metabolism health]

The positive effects of dietary fiber are related, in part, to the fact that a portion of the fermentation of components takes place in the large intestine, which has an impact on the speed of digestion, pH of the colon, and production of by-products with important physiological functions. Individuals with high fiber intake seem to have lower risk of developing coronary artery disease, hypertension, obesity, diabetes, and colon cancer. The increase in fiber intake reduces serum cholesterol, improves blood glucose in patients with diabetes, reduces body weight, and is associated with lower serum ultrasensitive C-reactive protein. Increased fiber intake and intake of more fiber than the currently recommended level (14 g/1,000 kcal) may provide greater health benefits, including reducing low-grade inflammation.

Effects of Dietary Supplementation with Agaricus sylvaticus Schaeffer on Glycemia and Cholesterol after Streptozotocin-Induced Diabetes in Rats

This study evaluated the effect of the Agaricus sylvaticus (sun mushroom) on biochemical tests of the plasma and on the morphology of the pancreas in an experimental model of type I diabetes mellitus (DM1) induced by streptozotocin. One gram of dry A. sylvaticus was homogenized and mixed with the chow. Male Wistar rats were allocated as follows: normoglycemic control that received commercial chow; normoglycemic control group that received chow with A. sylvaticus; diabetic group that received commercial chow; and diabetic group that received chow with A. sylvaticus. Weight, food, and water consumption were measured every two days. Blood glucose levels were measured twice a week. After 30 days, the animals were euthanized and blood was collected for the analysis of cholesterol, HDL, triglycerides, blood sugar, glutamic-pyruvic transaminase (GPT), alkaline phosphatase, iron, transferrin, and urea. The pancreas was processed for microscopic analysis. A. sylvaticus modulated the levels of cholesterol, HDL, triglycerides, blood sugar, GPT, alkaline phosphatase, iron, transferrin, and urea to levels similar to those found in the controls and led to compensatory hyperplasia of the islets of Langerhans. A. sylvaticus is potentially beneficial in the control of type 1 diabetes, and it may also prevent pancreas damage.

Raisin consumption by humans: effects on glycemia and insulinemia and cardiovascular risk factors

Raisins are widely recommended as good foods and preferred snacks because of their nutrient content. They are rich in dietary fiber, potassium, and many health-promoting phytonutrients and antioxidants. Raisins have a high dietary fiber score. Laboratory studies document that raisins rank in the upper quartile of foods for antioxidant content. Clinical research related to the potential health benefits of raisins has intensified over the past 10 y. Much of this research has focused on blood glucose and insulin responses to raisins compared to other foods or snacks. Meal studies indicate that raisins have a low to moderate glycemic index and a low insulinemic index. Longer term studies suggest that customary intake of raisins is associated with lower postprandial blood glucose values than with equicaloric control foods. Cross-sectional studies suggest that higher levels of dried fruit consumption are associated with lower systolic and diastolic blood pressure than seen with minimal dried fruit use. One clinical study documents that raisin intake over 12 wk is accompanied by a significant reduction in blood pressure. Preliminary results indicate that raisins are associated with increased satiety and decreased food consumption over an 8-h period, but the potential benefits of raisins for weight loss have not been assessed. Raisin intake is accompanied by reductions in serum low-density lipoprotein cholesterol, triglycerides, and oxidized low-density cholesterol values. Thus, raisins have the potential to significantly reduce the risk for developing diabetes or cardiovascular disease.

Viscous versus nonviscous soluble fiber supplements: mechanisms and evidence for fiber-specific health benefits

PURPOSE

This review focuses on the health benefits of viscous versus nonviscous soluble fibers, why symptoms can occur with increased fiber consumption, and how to avoid symptoms to improve adherence with a high-fiber diet.

DATA SOURCES

Review of scientific literature as well as evidence-based guidelines and resources.

CONCLUSIONS

While it is generally known that "fiber is good for you," it is less well known that specific health benefits are associated with specific fiber characteristics. Many of the health benefits of fiber can be directly correlated with the viscosity of soluble fibers when hydrated (i.e., gel-forming). A reduction in viscosity of a given fiber will attenuate these health benefits, and a nonviscous fiber does not exhibit these health benefits.

IMPLICATIONS FOR PRACTICE

Increasing the viscosity of chyme with a viscous soluble fiber has been shown clinically to lower cholesterol for cardiovascular health, improve glycemic control in type 2 diabetes, normalize stool form in both constipation (softens hard stool) and diarrhea (firms loose/liquid stool), and improve the objective clinical measures of metabolic syndrome (glycemic control, lipoprotein profile, body mass index/weight loss, and blood pressure).

Effects of psyllium on metabolic syndrome risk factors

High-fibre intake has been shown to reduce the risk of metabolic syndrome (MS), cardiovascular disease and type 2 diabetes. Psyllium is one of the most widely used fibre supplements because it is reasonably cheap and is better tolerated than other fibre supplements. The review of the literature supports the notion that the consumption of psyllium provides benefits to many components of the MS. Psyllium supplementation does improve glucose levels and insulin response, blood pressure, as well as lipid profile in both animals and humans, thereby reducing metabolic risk factors. Appetite has also been reported to decrease after the consumption of psyllium in most studies. Collectively, psyllium supplementation could be promoted to patients who present MS risk factors, such as hypercholesterolaemia, hypertriglyceridaemia and hyperglycaemia. It may also play a role in controlling body weight, body composition, appetite and hypertension, but further investigation is still required.

Beta glucan: health benefits in obesity and metabolic syndrome

Despite the lack of international agreement regarding the definition and classification of fiber, there is established evidence on the role of dietary fibers in obesity and metabolic syndrome. Beta glucan (β-glucan) is a soluble fiber readily available from oat and barley grains that has been gaining interest due to its multiple functional and bioactive properties. Its beneficial role in insulin resistance, dyslipidemia, hypertension, and obesity is being continuously documented. The fermentability of β-glucans and their ability to form highly viscous solutions in the human gut may constitute the basis of their health benefits. Consequently, the applicability of β-glucan as a food ingredient is being widely considered with the dual purposes of increasing the fiber content of food products and enhancing their health properties. Therefore, this paper explores the role of β-glucans in the prevention and treatment of characteristics of the metabolic syndrome, their underlying mechanisms of action, and their potential in food applications.

Polyphenol-rich strawberry pomace reduces serum and liver lipids and alters gastrointestinal metabolite formation in fructose-fed rats

This study compared the effects of supplementation with a polyphenol-rich pomace from strawberry (US) and a strawberry pomace without most of these compounds (PS) on gastrointestinal, blood, and tissue biomarkers in rats fed diets differing in carbohydrate contents for 4 wk. The diets were: corn starch (group CS), high fructose (60% by weight; group F), starch with 7.7% of either US or PS (groups CS+US and CS+PS, respectively), and high fructose with 7.7% of either US or PS (groups F+US and F+PS, respectively). An interaction (P < 0.05) was observed between diet type and strawberry preparation, showing that upon fructose feeding, US had a greater effect than PS on lowering serum insulin, liver total cholesterol, and conjugated dienes. Additionally, the F+US group had lower serum FFA than the F+PS group (P < 0.05). The extraction of polyphenols diminished the physiological effect associated with strawberry intake, suggesting that the fiber component of the pomace was also active in reducing metabolic complications following fructose feeding to rats.

Symptoms associated with dietary fiber supplementation over time in individuals with fecal incontinence

BACKGROUND

Knowledge about adverse symptoms over time from fiber supplementation is lacking.

PURPOSE

The aim of this study was to compare the severity of adverse gastrointestinal (GI) symptoms during supplementation with dietary fiber or placebo over time in adults with fecal incontinence. A secondary aim was to determine the relationship between symptom severity and emotional upset and their association with study attrition and reducing fiber dose.

METHODS

Participants (N = 189; 77% female; 92% White; age, M = 58 years, SD = 14 years) with fecal incontinence were randomly assigned to a placebo or a supplement of 16 g total dietary fiber per day from 1 of 3 sources: gum arabic, psyllium, or carboxymethylcellulose. They reported GI symptoms daily during baseline (14 days), incremental fiber dosing (6 days), and 2 segments of steady full fiber dose (32 days total).

RESULTS

Severity of symptoms in all groups was minimal. Adjusting for study segment and day, a greater feeling of fullness in the psyllium group was the only symptom that differed from symptoms in the placebo group. The odds of having greater severity of flatus, belching, fullness, and bloating were 1.2-2.0 times greater in the steady dose segment compared with baseline. There was a positive association between symptom severity and emotional upset. Participants with a greater feeling of fullness or bloating or higher scores for total symptom severity or emotional upset were more likely to withdraw from the study sooner or reduce fiber dose.

CONCLUSIONS

Persons with fecal incontinence experience a variety of GI symptoms over time. Symptom severity and emotional upset appear to influence fiber tolerance and study attrition. Supplements seemed well tolerated.

The right fiber for the right disease: an update on the psyllium seed husk and the metabolic syndrome

The metabolic syndrome (MS) is a clustering of hyperglycemia/insulin resistance, dyslipidemia, overweight and hypertension. MS identifies patients who are at high risk of developing atherosclerotic cardiovascular disease (CVD) and type 2 diabetes (T2D). Based on current data dietary fibre intake from whole foods or supplements may lower blood pressure, may improve serum lipid levels, may reduce indicators of inflammations,may lower serum glucose levels and favour body weight loss. US Food and Drug Administration in 2006 authorized a health claim that psyllium husk, beta glucan in oats and beta glucan in barley can reduce the risk of heart disease. Solubility in water, viscosity, fermentability, and the kind and amounts of protein and tocotrienols have been explored as possible basis for this effect. In particular, many experimental and clinical studies suggest that psyllium does lower serum and liver cholesterol concentrations and may increase HDL-cholesterol levels- Moreover,water soluble fibres, such as psyllium, moderate post prandial glucose and insulin concentrations in non-insulin dependent diabetic patients, if taken with meals and favour the reduction of body weight and hypertension. Therefore, the favourable effect of various fibres and particularly of psyllium, on body weight reduction and satiety, on cholesterol and tryglycerides levels, on fasting glycaemia and on blood pressure suggests a potential role of these fibres in the treatment of MS.

The effect of a fibre supplement compared to a healthy diet on body composition, lipids, glucose, insulin and other metabolic syndrome risk factors in overweight and obese individuals

Optimum levels and types of dietary fibre that provide the greatest beneficial effects on metabolic syndrome risk factors in overweight and obese individuals have yet to be determined in clinical trials. The present parallel design study compared the effects of fibre intake from a healthy dietv. a fibre supplement (psyllium) or a healthy diet plus fibre supplement on fasting lipids, glucose, insulin and body composition. Overweight/obese adults were randomised to either control (with placebo), fibre supplement (FIB), healthy eating plus placebo (HLT) or healthy eating plus fibre supplement (HLT–FIB). There was a significant increase in fibre intake in HLT–FIB, HLT and FIB groups up to 59, 31 and 55 g, respectively, at 12 weeks when compared to control (20 g). Weight, BMI and % total body fat were significantly reduced in FIB and HLT–FIB groups, with weight and BMI significantly reduced in the HLT group compared with control at 12 weeks. HLT–FIB and HLT groups had significant reductions in TAG and insulin compared with control at 6 and 12 weeks, and in insulin compared with the FIB group at 12 weeks. The HLT–FIB, HLT and FIB groups all had significant reductions in total cholesterol and LDL-cholesterol compared with control after 6 and 12 weeks. The present study demonstrated that simply adding psyllium fibre supplementation to a normal diet was sufficient to obtain beneficial effects in risk factors. However, a high-fibre diet consisting of a psyllium supplement plus fibre from a healthy diet provided the greatest improvements in metabolic syndrome risk factors.

Whole-grain ready-to-eat oat cereal, as part of a dietary program for weight loss, reduces low-density lipoprotein cholesterol in adults with overweight and obesity more than a dietary program including low-fiber control foods

OBJECTIVE

Weight loss and consumption of viscous fibers both lower low-density lipoprotein (LDL) cholesterol levels. We evaluated whether or not a whole-grain, ready-to-eat (RTE) oat cereal containing viscous fiber, as part of a dietary program for weight loss, lowers LDL cholesterol levels and improves other cardiovascular disease risk markers more than a dietary program alone.

DESIGN

Randomized, parallel-arm, controlled trial.

SUBJECTS/SETTING

Free-living, overweight and obese adults (N=204, body mass index 25 to 45) with baseline LDL cholesterol levels 130 to 200 mg/dL (3.4 to 5.2 mmol/L) were randomized; 144 were included in the main analysis of participants who completed the trial without significant protocol violations.

INTERVENTION

Two portions per day of whole-grain RTE oat cereal (3 g/day oat b-glucan) or energy-matched low-fiber foods (control), as part of a reduced energy ( approximately 500 kcal/day deficit) dietary program that encouraged limiting consumption of foods high in energy and fat, portion control, and regular physical activity.

MAIN OUTCOME MEASURES

Fasting lipoprotein levels, waist circumference, triceps skinfold thickness, and body weight were measured at baseline and weeks 4, 8, 10, and 12.

RESULTS

LDL cholesterol level was reduced significantly more with whole-grain RTE oat cereal vs control (-8.7+/-1.0 vs -4.3+/-1.1%, P=0.005). Total cholesterol (-5.4+/-0.8 vs -2.9+/-0.9%, P=0.038) and non-high-density lipoprotein-cholesterol (-6.3+/-1.0 vs -3.3+/-1.1%, P=0.046) were also lowered significantly more with whole-grain RTE oat cereal, whereas high-density lipoprotein and triglyceride responses did not differ between groups. Weight loss was not different between groups (-2.2+/-0.3 vs -1.7+/-0.3 kg, P=0.325), but waist circumference decreased more (-3.3+/-0.4 vs -1.9+/-0.4 cm, P=0.012) with whole-grain RTE oat cereal. Larger reductions in LDL, total, and non-high-density lipoprotein cholesterol levels and waist circumference were evident as early as week 4 in the whole-grain RTE oat cereal group.

CONCLUSIONS

Consumption of a whole-grain RTE oat cereal as part of a dietary program for weight loss had favorable effects on fasting lipid levels and waist circumference.

Dietary fiber supplements: effects in obesity and metabolic syndrome and relationship to gastrointestinal functions

Dietary fiber is a term that reflects a heterogeneous group of natural food sources, processed grains, and commercial supplements. Several forms of dietary fiber have been used as complementary or alternative agents in the management of manifestations of the metabolic syndrome, including obesity. Not surprisingly, there is a great variation in the biological efficacy of dietary fiber in the metabolic syndrome and body weight control. Diverse factors and mechanisms have been reported as mediators of the effects of dietary fiber on the metabolic syndrome and obesity. Among this array of mechanisms, the modulation of gastric sensorimotor influences appears to be crucial for the effects of dietary fiber but also quite variable. This report focuses on the role, mechanism of action, and benefits of different forms of fiber and supplements on obesity and the metabolic syndrome, glycemia, dyslipidemia, and cardiovascular risk and explores the effects of dietary fiber on gastric sensorimotor function and satiety in mediating these actions of dietary fiber.

Functional foods for dyslipidaemia and cardiovascular risk prevention

A food can be regarded as ‘functional’ if it can demonstrate a beneficial efficacy on one or more target functions in the body in a convincing way. Beyond adequate nutritional qualities, functional foods should either improve the state of health and wellbeing and/or reduce the risk of disease. Functional foods that are marketed with claims of heart disease reduction focus primarily on the major risk factors, i.e. cholesterol, diabetes and hypertension. Some of the most innovative products are designed to be enriched with ‘protective’ ingredients, believed to reduce risk. They may contain, for example, soluble fibre (from oat and psyllium), useful both for lowering cholesterol and blood pressure, or fructans, effective in diabetes. Phytosterols and stanols lower LDL-cholesterol in a dose-dependent manner. Soya protein is more hypocholesterolaemic in subjects with very high initial cholesterol and recent data indicate also favourable activities in the metabolic syndrome.n-3 Fatty acids appear to exert significant hypotriacylglycerolaemic effects, possibly partly responsible for their preventive activity. Dark chocolate is gaining much attention for its multifunctional activities, useful both for the prevention of dyslipidaemia as well as hypertension. Finally, consensus opinions about tea and coffee have not emerged yet, and the benefits of vitamin E, garlic, fenugreek and policosanols in the management of dyslipidaemia and prevention of arterial disease are still controversial.

A controlled study of consumption of β-glucan-enriched soups for 2 months by type 2 diabetic free-living subjects

Type 2 diabetes is associated with a higher cardiovascular risk and there has been a growing interest in using dietary intervention to improve lipid profile and glucose control. The present work aims at analysing the effects of the enrichment of a normal diet with β-glucan (3·5 g/d) in free-living type 2 diabetic subjects for 2 months, using a palatable soup. This trial was a parallel, placebo-controlled, double-blinded randomised study performed in fifty-three type 2 diabetic subjects. During a 3-week run-in period, subjects daily consumed a ready meal control soup (without β-glucan). For the following 8 weeks, subjects were randomly assigned to consume daily either a control soup or a β-glucan soup. Changes in lipid profile (total cholesterol (TC), HDL- and LDL-cholesterol (HDLc and LDLc), apo B and TAG) and in glucose control (HbA1c and fasting glucose) were measured. There was no significant alteration in lipid profile in the two groups (TC, HDLc, LDLc and apo B). TAG decreased significantly in the β-glucan group compared with the control group ( − 0·12 (sd0·38)v. 0·12 (sd0·44) mmol/l,P = 0·03). HbA1c and fasting glucose were not reduced in any group. A single daily ingestion of 3·5 g β-glucan, as required by official dietary recommendations, for 8 weeks did not change the lipid profile and HbA1c in type 2 diabetic subjects. To improve the metabolic profile of type 2 diabetic subjects in the long term, the quantity, the food vectors and the tolerability of β-glucan products may be re-evaluated.

Dietary fiber improves lipid homeostasis and modulates adipocytokines in hamsters

BACKGROUND

The hypocholesterolemic and hypoglycemic effects of various natural and semisynthetic dietary fibers have been studied for their potential use in the prevention and improvement of metabolic syndrome. Of these dietary fibers, hydroxypropyl methylcellulose (HPMC) has been shown to lower plasma cholesterol and reduce weight gain. However, the underlying mechanisms are not known. In the present study, we examined associations between plasma adipocytokine levels and both lipid metabolism and insulin sensitivity after HPMC intake in golden Syrian hamsters. In addition, endogenous adiponectin from hamster plasma was purified and characterized.

METHODS

Hamsters were treated with HPMC (2% and 4% in a high-fat diet) or 2% or 4% microcrystalline cellulose (MCC; control diet) for 8 weeks. Plasma glucose, insulin, lipids, adiponectin, leptin, and hepatic lipid levels were assessed using standard techniques.

RESULTS

After 8 weeks of feeding, plasma total cholesterol and triglyceride levels in hamsters fed the 4% HPMC-supplemented diet were significantly lower than in hamsters fed the control diet. Moreover, a significant increase in adiponectin levels and a decrease in leptin levels were observed in hamsters fed the 4% HPMC-supplemented diet. Hamster adiponectin was found to be comprised of 244 amino acid residues with an apparent molecular weight of 30 kDa, consistent with the adiponectin reported in other species.

CONCLUSIONS

Reductions in plasma cholesterol and triglyceride levels were correlated with a decrease in plasma leptin and an increase in adiponectin. These results suggest that adipocytokines are regulated by HPMC and may play a pivotal role in the hypocholesterolemic effect.

Health benefits of dietary fiber

Dietary fiber intake provides many health benefits. However, average fiber intakes for US children and adults are less than half of the recommended levels. Individuals with high intakes of dietary fiber appear to be at significantly lower risk for developing coronary heart disease, stroke, hypertension, diabetes, obesity, and certain gastrointestinal diseases. Increasing fiber intake lowers blood pressure and serum cholesterol levels. Increased intake of soluble fiber improves glycemia and insulin sensitivity in non-diabetic and diabetic individuals. Fiber supplementation in obese individuals significantly enhances weight loss. Increased fiber intake benefits a number of gastrointestinal disorders including the following: gastroesophageal reflux disease, duodenal ulcer, diverticulitis, constipation, and hemorrhoids. Prebiotic fibers appear to enhance immune function. Dietary fiber intake provides similar benefits for children as for adults. The recommended dietary fiber intakes for children and adults are 14 g/1000 kcal. More effective communication and consumer education is required to enhance fiber consumption from foods or supplements.

Lipid-altering effects of different formulations of hydroxypropylmethylcellulose

BACKGROUND

Hydroxypropylmethylcellulose (HPMC), a viscous, soluble dietary fiber, has been shown to be efficacious for lowering total and low-density lipoprotein cholesterol (LDL-C) concentrations. The relative effects of various dosages and viscosities of HPMC have not been fully evaluated.

OBJECTIVE

To examine the lipid-altering effects of several formulations of HPMC.

METHODS

In this randomized, double-blind pilot study, 165 men and women with primary hypercholesterolemia consumed a control product (snack bar or drink mix) or an HPMC-containing test bar or drink for 4 weeks. HPMC-containing products delivered 3, 5, or 10g of HPMC of low, moderate, moderately high, or high viscosity (9 HPMC groups, each with ∼15 subjects).

RESULTS

Data from drink and bar groups were combined because there was no evidence of a vehicle effect. The resulting analysis included data from the control and 6 HPMC dose and viscosity combinations. All HPMC groups showed LDL-C reductions ranging from 6.1 to 13.3% (P < .05 vs. baseline for 6 of the 7 groups), compared with a nonsignificant reduction (1.9%) in the control group. Changes in total and non-high-density lipoprotein cholesterol paralleled those for LDL-C. Concentrations of high-density lipoprotein cholesterol, triglycerides, apolipoprotein B, and high-sensitivity C-reactive protein were not significantly altered.

CONCLUSION

This pilot study provides preliminary evidence to support the efficacy of various formulations of HPMC for reducing cholesterol carried by atherogenic particles in men and women with primary hypercholesterolemia. Additional research will be required to more clearly define the roles of viscosity and dosage on the lipid-altering effects of HPMC.