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

Natural products for managing metabolic syndrome: a scoping review

Introduction

Metabolic syndrome comprises a collection of metabolic disorders stemming from factors like genetic predisposition, inadequate nutrition, stress, decreased physical activity, aging, and ethnicity. Although traditional pharmaceutical treatments exist for metabolic syndrome, their limited popularity is attributed to high costs and adverse effects. Consequently, natural products with fewer side effects have been explored for managing this condition. This literature review aims to explore the role of natural products including herbs, botanicals, vitamins, minerals, probiotics, and dietary supplements in managing metabolic syndrome.

Methods

This scoping review was conducted in five steps, involving the formulation of a research question, the retrieval and extraction of relevant studies, the selection of pertinent studies, the organization of information into tables, and the reporting of results. Data was collected from various databases including Embase, Science Direct, PubMed, Google Scholar, Scopus, and Web of Science, with a focus on studies published from 2010 to the present, available in English and with full-text accessibility.

Results

We identified 1,259 articles, screened their titles, abstracts, and full texts, ultimately incorporating 169 pertinent articles into this review (comprising 90 review articles, 32 trial articles, 6 in vitro articles, 38 in vivo articles, 1 experimental article and 2 observational articles). The study's outcomes revealed that natural products, encompassing plants and their derivatives, vitamins and supplements, as well as probiotics, can exert a beneficial influence on metabolic syndrome by regulating blood sugar, blood pressure, lipid profiles, obesity, and abnormal cholesterol and triglyceride levels.

Conclusion

The current study underscores the significance of natural products in addressing metabolic syndrome. Consequently, it is advisable to conduct further extensive research to assess the efficacy of these products, potentially integrating them into treatment regimens for individuals with metabolic syndrome.

Natural products for managing metabolic syndrome: a scoping review

Introduction

Metabolic syndrome comprises a collection of metabolic disorders stemming from factors like genetic predisposition, inadequate nutrition, stress, decreased physical activity, aging, and ethnicity. Although traditional pharmaceutical treatments exist for metabolic syndrome, their limited popularity is attributed to high costs and adverse effects. Consequently, natural products with fewer side effects have been explored for managing this condition. This literature review aims to explore the role of natural products including herbs, botanicals, vitamins, minerals, probiotics, and dietary supplements in managing metabolic syndrome.

Methods

This scoping review was conducted in five steps, involving the formulation of a research question, the retrieval and extraction of relevant studies, the selection of pertinent studies, the organization of information into tables, and the reporting of results. Data was collected from various databases including Embase, Science Direct, PubMed, Google Scholar, Scopus, and Web of Science, with a focus on studies published from 2010 to the present, available in English and with full-text accessibility.

Results

We identified 1,259 articles, screened their titles, abstracts, and full texts, ultimately incorporating 169 pertinent articles into this review (comprising 90 review articles, 32 trial articles, 6 in vitro articles, 38 in vivo articles, 1 experimental article and 2 observational articles). The study’s outcomes revealed that natural products, encompassing plants and their derivatives, vitamins and supplements, as well as probiotics, can exert a beneficial influence on metabolic syndrome by regulating blood sugar, blood pressure, lipid profiles, obesity, and abnormal cholesterol and triglyceride levels.

Conclusion

The current study underscores the significance of natural products in addressing metabolic syndrome. Consequently, it is advisable to conduct further extensive research to assess the efficacy of these products, potentially integrating them into treatment regimens for individuals with metabolic syndrome.

The role of body mass index on the association between the energy-adjusted dietary inflammatory index and hyperuricemia: a mediation analysis based on NHANES (2007-2016)

BACKGROUND

The Energy-Adjusted Dietary Inflammatory Index (E-DII) is related to both body mass index (BMI) and hyperuricemia. However, the association among BMI, hyperuricemia and DII is yet to be fully elucidated. The purpose of this study is to explore the role of BMI in the relationship between E-DII and hyperuricemia in the American population.

METHODS

A cross-sectional study was conducted using data from the National Health and Nutrition Examination Survey (NHANES) spanning from 2007 to 2016, with a sample size of 10,571 participants. The study used a weighted logistic regression model and a generalized additive model (GAM) to explore the associations among BMI, hyperuricemia and E-DII. Furthermore, mediation analysis was utilized to illustrate the mediating relationships among these variables.

RESULTS

The results of the study indicated that a higher E-DII was related to an increased risk of hyperuricemia. The association between E-DII and hyperuricemia was partially mediated by BMI.

CONCLUSIONS

E-DII is associated with hyperuricemia. BMI mediates the relationship between E-DII and hyperuricemia among Americans, which provides crucial information for the prevention of hyperuricemia.

Barley consumption under a high-fat diet suppresses lipogenic genes through altered intestinal bile acid composition

We evaluated whether barley flour consumption in a high-fat environment affects lipid metabolism through signals mediated by bile acids. Four-week-old mice were fed a high-fat diet supplemented with cellulose (HC) or β-glucan-rich barley flour (HB) for 12 weeks. Bile acid composition in the intestinal tract and feces was measured by GC/MS. Gene expression levels involved in bile acid metabolism in the liver and intestinal tract were determined by RT-PCR. Similar parameters were measured in mice treated with antibiotics (antibiotics-cellulose [AC] and antibiotics-barley [AB]) to reduce the activity of intestinal bacteria. The Results showed that the HB group had lower liver blood cholesterol and triglyceride levels than the HC group. The HB group showed a significant decrease in primary bile acids in the gastrointestinal tract compared to the HC group. On the other hand, the concentration of secondary bile acids relatively increased in the cecum and feces. In the liver, Fxr activation suppressed gene expression levels in synthesizing bile acids and lipids. Furthermore, in the gastrointestinal tract, Tgr5 was activated by increased secondary bile acids. Correspondingly, AMP levels were increased in the HB group compared to the HC group, AMPK was phosphorylated in the liver, and gene expression involved in lipid synthesis was downregulated. A comparison of the AC and AB groups treated with antibiotics did not confirm these effects of barley intake. In summary, our results suggest that the prevention of lipid accumulation by barley consumption involves signaling through changes in bile acid composition in the intestinal tract.

Efficacy of Butyrate to Inhibit Colonic Cancer Cell Growth Is Cell Type-Specific and Apoptosis-Dependent

Increasing dietary fiber consumption is linked to lower colon cancer incidence, and this anticancer effect is tied to elevated levels of short-chain fatty acids (e.g., butyrate) because of the fermentation of fiber by colonic bacteria. While butyrate inhibits cancer cell proliferation, the impact on cancer cell type remains largely unknown. To test the hypothesis that butyrate displays different inhibitory potentials due to cancer cell type, we determined half-maximal inhibitory concentrations (IC50) of butyrate in HCT116, HT-29, and Caco-2 human colon cancer cell proliferation at 24, 48, and 72 h. The IC50 (mM) butyrate concentrations of HCT116, HT-29, and Caco-2 cells were [24 h, 1.14; 48 h, 0.83; 72 h, 0.86], [24 h, N/D; 48 h, 2.42; 72 h, 2.15], and [24 h, N/D; 48 h, N/D; 72 h, 2.15], respectively. At the molecular level, phosphorylated ERK1/2 and c-Myc survival signals were decreased by (>30%) in HCT116, HT-29, and Caco-2 cells treated with 4 mM butyrate. Conversely, butyrate displayed a stronger potential (>1-fold) for inducing apoptosis and nuclear p21 tumor suppressor in HCT116 cells compared to HT-29 and Caco-2 cells. Moreover, survival analysis demonstrated that a cohort with high p21 gene expression in their colon tissue significantly increased survival time compared to a low-p21-expression cohort of colon cancer patients. Collectively, the inhibitory efficacy of butyrate is cell type-specific and apoptosis-dependent.

Postprandial glucose metabolism in children and adolescents with type 1 diabetes mellitus: potential targets for improvement

The main goal of therapeutic management of type 1 Diabetes Mellitus (T1DM) is to maintain optimal glycemic control to prevent acute and long-term diabetes complications and to enable a good quality of life. Postprandial glycemia makes a substantial contribution to overall glycemic control and variability in diabetes and, despite technological advancements in insulin treatments, optimal postprandial glycemia is difficult to achieve. Several factors influence postprandial blood glucose levels in children and adolescents with T1DM, including nutritional habits and adjustment of insulin doses according to meal composition. Additionally, hormone secretion, enteroendocrine axis dysfunction, altered gastrointestinal digestion and absorption, and physical activity play important roles. Meal-time routines, intake of appropriate ratios of macronutrients, and correct adjustment of the insulin dose for the meal composition have positive impacts on postprandial glycemic variability and long-term cardiometabolic health of the individual with T1DM. Further knowledge in the field is necessary for management of all these factors to be part of routine pediatric diabetes education and clinical practice. Thus, the aim of this report is to review the main factors that influence postprandial blood glucose levels and metabolism, focusing on macronutrients and other nutritional and lifestyle factors, to suggest potential targets for improving postprandial glycemia in the management of children and adolescents with T1DM.

Insoluble/soluble fraction ratio determines effects of dietary fiber on gut microbiota and serum metabolites in healthy mice

Both soluble dietary fiber (SDF) and insoluble dietary fiber (IDF) play pivotal roles in maintaining gut microbiota homeostasis; whether the effects of the different ratios of IDF and SDF are consistent remains unclear. Consequently, we selected SDFs and IDFs from six representative foods (apple, celery, kale, black fungus, oats, and soybeans) and formulated nine dietary fiber recipes composed of IDF and SDF with a ratio from 1 : 9 to 9 : 1 (NDFR) to compare their impact on microbial effects with healthy mice. We discovered that NDFR treatment decreased the abundance of Proteobacteria and the ratio of Firmicutes/Bacteroidetes at the phylum level. The α diversity and relative richness of Parabacteroides and Prevotella at the genus level showed an upward trend along with the ratio of IDF increasing, while the relative abundance of Akkermansia at the genus level and the production of acetic acid and propionic acid exhibited an increased trend along with the ratio of SDF increasing. The relative abundance of Parabacteroides and Prevotella in the I9S1DF group (the ratio of IDF and SDF was 9 : 1) was 1.72 times and 5.92 times higher than that in the I1S9DF group (the ratio of IDF and SDF was 1 : 9), respectively. The relative abundance of Akkermansia in the I1S9DF group was 17.18 times higher than that in the I9S1DF group. Moreover, a high ratio of SDF (SDF reaches 60% or more) enriched the glycerophospholipid metabolism pathway; however, a high ratio of IDF (IDF reaches 80% or more) regulated the tricarboxylic acid cycle. These findings are helpful in the development of dietary fiber supplements based on gut microbiota and metabolites.

Overview of Natural Supplements for the Management of Diabetes and Obesity

Bioactive compounds found in various natural sources, such as fruits, vegetables, and herbs, have been studied for their potential benefits in managing obesity and diabetes. These compounds include polyphenols, flavonoids, other antioxidants, fiber, and certain fatty acids. Studies have found that these compounds may improve insulin sensitivity, regulate blood sugar levels, and promote weight loss. However, the effects of these compounds can vary depending on the type and amount consumed, as well as individual factors, such as genetics and lifestyle. Nutraceutical substances have multifaceted therapeutic advantages, and they have been reported to have disease-prevention and health-promoting properties. Several clinically used nutraceuticals have been shown to target the pathogenesis of diabetes mellitus, obesity, and metabolic syndrome and their complications and modulate various clinical outcomes favorably. This review aims to highlight and comment on some of the most prominent natural components used as antidiabetics and in managing obesity.

Pomelo peel dietary fiber ameliorates alterations in obesity-related features and gut microbiota dysbiosis in mice fed on a high-fat diet

Pomelo peel has abundance of dietary fiber and various biological activities but is often discarded as waste. This study evaluated the biological activities of pomelo peel dietary fiber (PPDF) in preventing obesity and regulating intestinal microbiota in obese mouse model induced using a high-fat diet (HFD). As for the composition, the prepared PPDF contained 89.64% of total dietary fiber, 53.27% of insoluble dietary fiber, and 36.37% of soluble dietary fiber. PPDF treatment significantly reduced weight gain and fat accumulation in the liver and epididymal tissues of obese mice; significantly alleviated HFD-induced dyslipidemia; and restored the levels of triglycerides, low-density lipoprotein-cholesterol, and high-density lipoprotein--cholesterol to control levels, and the PPDF 5% dose restored total cholesterol to the control level. Furthermore, PPDF ameliorated HFD-induced gut microbiota dysbiosis by increasing intestinal microbial diversity, decreasing the Firmicutes/Bacteroidetes ratio, increasing beneficial bacteria (Bifidobacterium, Alloprevotella, and Lactobacillus), and decreasing harmful bacteria (Staphylococcus and Corynebacterium_1). This study provided a new idea to use PPDF as functional food to prevent obesity, alleviate dyslipidemia, or a potential probiotic to ameliorate gut microbiota dysbiosis.

Dietary carbohydrate quality index (CQI), cardio-metabolic risk factors and insulin resistance among adults with obesity

BACKGROUND

Metabolic syndrome (MetS), as a cluster of cardiometabolic risk factors, is a global public health concern due to its increasing prevalence. Considering the previous evidence of the association between carbohydrate quality and cardiometabolic risk factors, our study was aimed to evaluate any possible association between carbohydrate quality index (CQI) and cardiometabolic risk factors among obese adults.

METHODS

In this cross-sectional study, 336 apparently healthy individuals with obesity were participated. Dietary intake was assessed by a semi-quantitative Food Frequency Questionnaire (FFQ), including 168 food items validated for the Iranian population. CQI was calculated with three components of solid carbohydrates to total carbohydrates ratio, dietary fiber intake, and dietary glycemic index (GI). Body composition was determined by bioelectrical impedance analysis (BIA). Blood pressure was measured by sphygmomanometer and enzymatic methods were used to evaluate serum lipid, glucose, and insulin concentrations.

RESULTS

Subjects in the third quartile of CQI had significantly lower systolic blood pressure (SBP) (P = 0.03) and diastolic blood pressure (DBP) (P = 0.01). Participants in the higher quartiles of CQI had more intake of energy, carbohydrates, fat, saturated fatty acid (SFA), and mono-saturated fatty acid (MUFA) (P < 0.05). Moreover, the homeostasis model assessment of insulin resistance (HOMA-IR) was decreased in the second quartile of CQI [odds ratio (OR) = 0.146, P = 0.01) after adjustment for age, body mass index (BMI), sex, physical activity, socioeconomic status (SES) and energy intake.

CONCLUSION

According to our findings, a higher quality of dietary carbohydrates, determined by CQI, could be associated with a lower risk of hypertension.

Acute Effects of Dietary Fiber in Starchy Foods on Glycemic and Insulinemic Responses: A Systematic Review of Randomized Controlled Crossover Trials

Dietary fiber (DF) consumption has been associated with improved glycemic control in epidemiological and long-term interventional studies. However, its acute effects are not yet clear. This systematic review aims to elucidate the postprandial effects of DF in starchy products on glycemia and insulinemia. An electronic search of databases was conducted, and forty-one records met the inclusion criteria and underwent a risk-of-bias assessment. It was shown that soluble DF does not clearly affect glycemia in individuals with normal weight, while resistant starch may be more effective in flattening glycemic responses. Concerning insulinemia, both soluble DF and resistant starch have mixed results, with either favorable or no effects. Data on insoluble DF and glucose metabolism are scarce. The same mixed results for glycemia can be seen in healthy volunteers with overweight/obesity, while resistant starch seems to improve insulinemic responses. Finally, more studies need to examine the acute effects of DF in starchy foods on glucose metabolism and insulin secretion in individuals facing glucose abnormalities. Additionally, more studies are needed to prove whether ingesting high-fiber carbohydrate-containing products per se can result in blunted glycemic and insulinemic responses and which DF type and amount are more effective.

Association of Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) diet and metabolically unhealthy overweight/obesity phenotypes among Iranian women: a cross sectional study

PURPOSE

Paradoxes have been found in obesity, including individuals with metabolically healthy obesity (MHO) and metabolically unhealthy obesity (MUHO), and diet may be one of the reasons for the creation of these metabolic phenotypes. Hence, the purpose of the present study was to investigate the association of the Mediterranean-DASH intervention for neurodegenerative delay (MIND) diet with metabolically unhealthy overweight/obesity (MUHOW/O) phenotypes.

METHODS

In this cross-sectional study, 229 overweight and obese women (body mass index (BMI) ≥ 25 kg/m2) aged 18-48 years were examined. Anthropometric measures and biochemical parameters were collected from all participants. The body composition of each participant was assessed using a bioelectrical impedance analyzer (BIA). The MIND diet score was determined based on 15 components using a valid and reliable food frequency questionnaire (FFQ) containing 147 items. Karelis criteria was used to determine metabolically healthy/unhealthy phenotype (MH/MUH).

RESULTS

Among the participants, 72.5% of individuals were identified as MUH and 27.5% as MH, with a mean ± standard deviation (SD) age of 36.16 (8.33) years. The results of our analysis showed that after controlling for age, energy intake, BMI, and physical activity, there was no significant association observed between overweight/obesity phenotypes with tertile 2 (T2) (OR: 2.01, 95% CI: 0.86-4.17, P-value = 0.10), T3 (OR: 1.89, 95% CI: 0.86-4.17, P-value = 0.11) of MIND score, and only the odds of MUH relative to MH with a marginal significant decreasing trend was observed from the second to the third tertile (1.89 vs. 2.01) (P - trend = 0.06). Also, after additional adjustment for marital status, the nonsignificant association between overweight/obesity phenotypes with tertile 2 (T2) (OR: 2.13, 95% CI: 0.89-5.10, P-value = 0.08), T3 (OR: 1.87, 95% CI: 0.83-4.23, P-value = 0.12) of MIND score remained, and the odds of MUH relative to MH with a significant decreasing trend was observed with increasing tertiles (P-trend = 0.04).

CONCLUSIONS

In conclusion, no significant associations were found between adherence to MIND diet with MUH, and only a significant downward trend in the odds of MUH was observed with increasing tertiles. We suggest further studies in this field.

The Implication of Short-Chain Fatty Acids in Obesity and Diabetes

Evidence indicates that short-chain fatty acids (SCFAs) generated from the gut microbiota play crucial roles in host metabolism. They contribute to metabolic regulation and energy acquisition of the host by influencing the development of metabolic disorders. This review aims to synthesize recent advances from the literature to investigate the implication of SCFAs in the modulation of obesity and diabetes pathologies. For a better understanding of the relationships between SCFAs and host metabolism, we need to answer some questions: What is the biochemistry of SCFAs, and how they are generated by gut microbiota? What are the bacteria producing of SCFAs and from which routes? How SCFAs are absorbed and transported in the gut by different mechanisms and receptors? How SCFAs involved in obesity and diabetes pathologies?

Bamboo Shoots Modulate Gut Microbiota, Eliminate Obesity in High-Fat-Diet-Fed Mice and Improve Lipid Metabolism

Bamboo shoots (BS) have a variety of nutritional benefits; however, their anti-obesity effect and its underlying mechanism of action are still unclear. In this study, we investigated the protective effect of BS against high-fat diet (HFD)-induced gut dysbiosis in mice. After 12 weeks of feeding C57BL/6J mice either on a normal or an HFD with or without BS, metabolic indicators, including blood lipids and glucose tolerance, were measured. 16S rRNA gene sequencing and metabolomics were used to identify alterations in gut microbiota composition and fecal metabolic profiling. The results demonstrated that BS supplementation reduced body weight by 30.56%, mitigated liver damage, and improved insulin resistance and inflammation in obese mice. In addition, BS increased short-chain fatty acid (SCFA) levels and SCFA-producing bacteria (e.g., Lachnospiraceae_NK4A136_group and Norank_f_Muribaculaceae), and reduced levels of harmful bacteria (e.g., Blautia and Burkholderia-Paraburkholderia). Finally, BS increased many beneficial fecal metabolites, such as fatty acids and bile acids, which are highly relevant to the altered gut microbiota. Based on the modulatory effect of BS on microbiota composition and gut metabolite levels observed in this study, we suggest that BS may be beneficial in treating obesity and its related complications.

The role of dietary fibers in regulating appetite, an overview of mechanisms and weight consequences

Dietary fibers prevent obesity through reduction of hunger and prolongation of satiety. A number of mechanical and endocrine signals from gastrointestinal tract are stimulated by fibers and their fermentation products, reach regions of brain involved in the regulation of appetite, and ultimately reduce food intake. Gastric distention, delayed gastric emptying, prevention of hypoglycemic, increased amounts of unabsorbed nutrients reaching to the ileum, and stimulation of enteroendocrine cells for secretion of cholecystokinin, glucagon-like peptide-1 (GLP-1), and peptide YY are among mechanisms of fibers in decreasing hunger and prolongation of satiety. Fermentation of fibers produces short-chain fatty acids that also stimulates enteroendocrine cells to secrete GLP-1 and PYY. Randomized controlled trials have shown reductions in energy intake and body weight along with increased satiation and reduced hunger following consumption of fibers. Prospective cohort studies have confirmed these results but the extent of weight loss in some studies has been small. Controversies exist between studies particularly for the effect of fibers on the gastrointestinal hormones, subsequent food intake, and the resultant weight loss. More studies are needed before a clear conclusion can be drawn especially for the effect of fibers on appetite-related hormones and weight loss.

Recent advances in the extraction, chemical composition, therapeutic potential, and delivery of cardamom phytochemicals

Dietary phytochemicals including plant-derived alkaloids, carotenoids, organosulfur compounds, phenolics, and phytosterols, are health-promoting bioactive compounds that help in the prevention and mitigation of chronic diseases and microbial infections beyond basic nutrition supply. This article covers recent advances in the extraction, chemical composition, therapeutic potential (nutraceutical and antimicrobial), and delivery of black and green cardamom-derived phytochemicals. In recent years, advance extraction techniques (e.g., enzyme- assisted-, instant controlled pressure drop-, microwave- assisted-, pressurized liquid-, sub- critical-, supercritical fluid-, and ultrasound-assisted extractions) have been applied to obtain phytochemicals from cardamom. The bioactive constituents identification techniques, specifically GC-MS analysis revealed that 1,8-cineole and α-terpinyl acetate were the principle bioactive components in black and green cardamom. Regarding therapeutic potential, research findings have indicated desirable health properties of cardamom phytochemicals, including antioxidant-, anti-hypercholesterolemic, anti-platelet aggregation, anti-hypertensive, and gastro-protective effects. Moreover, antimicrobial investigations revealed that cardamom phytochemicals effectively inhibited growth of pathogenic microorganisms (bacteria and fungi), biofilm formation inhibition (Gram-negative and Gram-positive bacteria) and bacterial quorum sensing inhibition. Encapsulation and delivery vehicles, including microcapsules, nanoparticles, nanostructured lipid carriers, and nanoliposomes were effective strategies to enhance their stability, bioavailability and bioefficacy. In conclusion, cardamom phytochemicals had promising therapeutic potentials (antioxidant and antimicrobial) due to polyphenols, thus could be used as functional additive to increase shelf life, inhibit oxidative rancidity and confer pleasant aroma to commercial edibles as well as mitigate oxidative stress and lifestyle related chronic diseases (e.g., cardiovascular and gastrointestinal diseases). A future perspective concerning the fabrication of functional foods, nutraceuticals and antibiotics to promote cardamom phytochemicals applications as biotherapeutic agents at large-scale requires thorough investigations, e.g., optimum dose and physical form of supplementation to obtain maximum health benefits.

The effects of chitosan supplementation on anthropometric indicators of obesity, lipid and glycemic profiles, and appetite-regulated hormones in adolescents with overweight or obesity: a randomized, double-blind clinical trial

Background

Chitosan is one of dietary fiber that has received great attention in improving obesity-related markers, but little is known on its effects on adolescents.

Objectives

To analyze the effects of chitosan supplementation on obesity-related cardiometabolic markers and appetite-related hormones in adolescents with overweight or obesity.

Methods and analysis

A randomized clinical trial was performed on 64 adolescents with overweight and obesity, who were randomly allocated to receive chitosan supplementation (n = 32) or placebo as control (n = 32) for 12 weeks. Anthropometric measures, lipid and glycemic profiles, and appetite-related hormones were examined.

Results

Sixty-one participants completed study (chitosan = 31, placebo = 30). Chitosan supplementation significantly improved anthropometric indicators of obesity (body weight: − 3.58 ± 2.17 kg, waist circumference: − 5.00 ± 3.11 cm, and body mass index: − 1.61 ± 0.99 kg/m² and − 0.28 ± 0.19 Z-score), lipid (triglycerides: − 5.67 ± 9.24, total cholesterol: − 14.12 ± 13.34, LDL-C: − 7.18 ± 10.16, and HDL-C: 1.83 ± 4.64 mg/dL) and glycemic markers (insulin: − 5.51 ± 7.52 μIU/mL, fasting blood glucose: − 5.77 ± 6.93 mg/dL, and homeostasis model assessment of insulin resistance: − 0.24 ± 0.44), and appetite-related hormones (adiponectin: 1.69 ± 2.13 ng/dL, leptin − 19.40 ± 16.89, and neuropeptide Y: − 41.96 ± 79.34 ng/dL). When compared with the placebo group, chitosan supplementation had greater improvement in body weight, body mass index (kg/m² and Z-score), waist circumference, as well as insulin, adiponectin, and leptin levels. Differences were significant according to P-value < 0.05.

Conclusion

Chitosan supplementation can improve cardiometabolic parameters (anthropometric indicators of obesity and lipid and glycemic markers) and appetite-related hormones (adiponectin, leptin, and NPY) in adolescents with overweight or obesity.

Lignocellulose, dietary fibre, inulin and their potential application in food

In recent years, due to food insecurity, lignocellulose, dietary fibre as well as inulin have received wider attention owing to their abundance and being relatively low-cost indigestible polysaccharides. Since the recognition, acceptance of the consumption and utilization of these polysaccharides, as well as their attraction in science and industry has grown tremendously. There have been further researches carried out to ascertain the fact that people who consume or utilize these polysaccharides have low exposure to some fatal life-threatening illnesses. Rich sources of indigestible polysaccharides such as vegetables, cereals, fruits and nuts are beneficial to good health as consuming them reduce the occurrence of degenerating diseases such as colon cancer, heart disease, diabetes, etc. Despite these increasing facts depicting their advantages in the state of human health, their intake and utilization still fall below the acceptable limit and the knowledge of how they work in the human body are minimal with their explicit actions not easily shown. Hence, this review gives a better understanding of the significance of lignocellulose, dietary fibre and inulin, their functions, classifications, types and applications in the food industry, thereby exposing their various uses as these polycarbohydrates were considered a waste before now.

Flaxseed Polysaccharide Alters Colonic Gene Expression of Lipid Metabolism and Energy Metabolism in Obese Rats

Obesity is one of the most serious public health challenges. Recently, we found that flaxseed polysaccharides (FPs) had an anti-obesity effect through promoting lipid metabolism, but the obesity-inhibiting pathway of FP is still unclear. In this study, after FP intervention in an obese rat model, a transcriptome study was performed to further investigate how FP intervention alters the gene expression of colonic epithelial tissues (CETs). The results showed that there were 3785 genes differentially expressed due to the FP intervention, namely 374 downregulated and 3411 upregulated genes. After analyzing all the differentially expressed genes, two classical KEGG pathways were found to be related to obesity, namely the PPAR-signaling pathway and energy metabolism, involving genes Fabp1–5, Lpl, Gyk, Qqp7, Pparg, Rxrg, Acsl1, Acsl4, Acsl6, Cpt1c, Car1–4, Ca5b, Car8, Car12–14, Cps1, Ndufa4l2, Cox6b2, Atp6v1g2, Ndufa4l2 and Cox4i2. QRT-PCR results showed a consistent expression trend. Our results indicate that FP promotes lipid metabolism by changing the expression of some key genes of CETs, thus inhibiting obesity.

Impacts of Pretreatment Techniques on the Quality of Tuber Flours

Besides dietary sources of energy, roots and tuber crops can also serve as functional foods and nutraceutical ingredients to be explored in disease risk reduction and wellness. However, they are easily spoiled because of their high moisture contents and enzymatic reactions. Therefore, this review aimed at gathering information on the effects of various pretreatment methods on the quality of tuber crops before converting them into flour. Studies reported by different scholars showed that there were significant differences in physicochemical and functional properties between untreated tuber and the treated tuber samples. The review also highlighted that the chemical treatment methods, particularly sulfite treatment, could increase the lightness value of the flour. In addition, blanching could induce a decrease in protein, ash, and fat. Despite this, blanching pretreatment techniques increased moisture and carbohydrate content. Chemical treatment increases the ash content, which might be responsible for chemical diffusion into the sample. The reviewed results showed that the application of different pretreatments on tuber crops significantly improves many quality characteristics such as color, fiber content, carbohydrate, and the functional properties used for value addition during food product development in the industry. Therefore, application of pretreatment methods particularly chemical treatments could enhance nutritional value, and functional and physical properties of tuber flours.

Evidence-Based and Emerging Dietary Approaches to Upper Disorders of Gut-Brain Interaction

Food ingestion is a major symptom trigger in functional esophageal and gastroduodenal disorders and gastroparesis. This review summarizes current knowledge and identifies areas of research on the role of food factors and the opportunities for dietary intervention in these disorders. While many patients experiencing functional esophageal and gastroduodenal disorders identify specific food items as symptom triggers, available data do not allow the identification of specific nutrient groups that are more likely to induce symptoms. In functional dyspepsia (FD), recent studies have shown the potential efficacy of a diet low in fermentable oligosaccharides, disaccharides, monosaccharides, and polyols, although the underlying mechanism of action is unclear. Reports of favorable responses to gluten elimination in patients with FD are confounded by the concomitant benefit of reduced intake of fructans, fermentable oligosaccharides, disaccharides, monosaccharides, and polyols present in wheat. Emerging data based on a 6-food elimination diet and confocal laser endomicroscopic evaluation of mucosal responses to food proteins suggest a role for duodenal allergic reactions in FD symptom generation. In patients with gastroparesis, a low-residue diet has been shown to improve symptoms. Novel dietary approaches under evaluation are the Mediterranean diet and the heating/cooling diet approach.

Glucocorticosteroids and the Risk of NAFLD in Inflammatory Bowel Disease

Each year, the incidence of nonalcoholic fatty liver (NAFLD) disease increases. NAFLD is a chronic disease. One of the most common causes of NAFLD is an inadequate lifestyle, which is characterized by a lack or low physical activity and eating highly processed foods rich in saturated fat and salt and containing low amount of fiber. Moreover, disturbances in intestinal microbiome and the use of certain drugs may predispose to NAFLD. NAFLD is an increasingly described disease in patients with inflammatory bowel disease (IBD). Recent data also indicate a frequent coexistence of metabolic syndrome in this group of patients. Certain groups of drugs also increase the risk of developing inflammation, liver fibrosis, and cirrhosis. Particularly important in the development of NAFLD are steroids, which are used in the treatment of many diseases, for example, IBD. NAFLD is one of the most frequent parenteral manifestations of the disease in IBD patients. However, there is still insufficient information on what dose and exposure time of selected types of steroids may lead to the development of NAFLD. It is necessary to conduct further research in this direction. Therefore, patients with IBD should be constantly monitored for risk factors for the development of NAFLD.

Empowering consumers to PREVENT diet-related diseases through OMICS sciences (PREVENTOMICS): protocol for a parallel double-blinded randomised intervention trial to investigate biomarker-based nutrition plans for weight loss

INTRODUCTION

Personalised nutrition holds immense potential over conventional one-size-fits-all approaches for preventing and treating diet-related diseases, such as obesity. The current study aims to examine whether a personalised nutritional plan produces more favourable health outcomes than a standard approach based on general dietary recommendations in subjects with overweight or obesity and elevated waist circumference.

METHODS AND ANALYSIS

This project is a 10-week parallel, double-blinded randomised intervention trial. We plan to include 100 adults aged 18-65 years interested in losing weight, with body mass index ≥27 but<40 kg/m² and elevated waist circumference (males >94 cm; females >80 cm). Participants will be categorised into one of five predefined 'clusters' based on their individual metabolic biomarker profile and genetic background, and will be randomised in a 1:1 ratio to one of two groups: (1) personalised plan group that will receive cluster-specific meals every day for 6 days a week, in conjunction with a personalised behavioural change programme via electronic push notifications; or (2) control group that will receive meals following the general dietary recommendations in conjunction with generic health behaviour prompts. The primary outcome is the difference between groups (personalised vs control) in the change in fat mass from baseline. Secondary outcomes include changes in weight and body composition, fasting blood glucose and insulin, lipid profile, adipokines, inflammatory biomarkers, and blood pressure. Other outcomes involve measures of physical activity and sleep patterns, health-related quality of life, dietary intake, eating behaviour, and biomarkers of food intake. The effect of the intervention on the primary outcome will be analysed by means of linear mixed models.

ETHICS AND DISSEMINATION

The protocol has been approved by the Ethics Committee of the Capital Region, Copenhagen, Denmark. Study findings will be disseminated through peer-reviewed publications, conference presentations and media outlets.

TRIAL REGISTRATION NUMBER

NCT04590989.

The Impact of Waxy Wheat Flour, Inulin and Guar Gum on Post-Prandial Glycaemic and Satiety Indices, Sensory Attributes and Shelf Life of Tandoori and Pita Breads

The purpose of this study was to develop two different functional breads (Pita and Tandoori) supplemented with novel functional ingredients: waxy wheat flour (15%), inulin (8%) and guar gum (2%) independently and in combination. The breads were submitted to sensory characteristics, shelf life, glycaemic and satiety indices assessments. Both guar gum and inulin independently and in combination significantly (p < 0.05) decreased post-prandial blood glucose and glycemic response of Pita (GI of guar gum bread was 55%, inulin 57%) and Tandoori (GI of guar gum bread was 57% and inulin bread was 60%) compared to the control breads (GI 100%). Moreover, the results of the area under the curve of satiety showed that the addition of functional ingredients increased satiety levels as follows: for Pita, control was 355, a combination of all ingredients was 418, inulin was 451 and guar gum was 452; for Tandoori, control was 329, a combination of all ingredients was 420, inulin was 381 and guar gum was 390. The results showed that all sensory characteristics were improved, and breads were acceptable (all obtained more than five points) when the highest proportions of ingredients were added. Similarly, the shelf life of supplemented Pita and Tandoori breads was improved with the addition of ingredients. Therefore, the functional ingredients such as inulin and guar gum can be used independently and in combination to reduce GI and increase satiety of Pita and Tandoori bread with acceptable quality and shelf life.

Differential Effect of Dietary Fibers in Intestinal Health of Growing Pigs: Outcomes in the Gut Microbiota and Immune-Related Indexes

Although dietary fibers (DFs) have been shown to improve intestinal health in pigs, it is unclear whether this improvement varies according to the type/source of DF. In the current study, we investigated the impact of dietary supplement (15%) of pea-hull fiber (PF), oat bran (OB), and their mixture (MIX, PF, and OB each accounted for 7.5%) in the growth performance as well as intestinal barrier and immunity-related indexes in growing pigs. Twenty-four cross-bred pigs (32.42 ± 1.95 kg) were divided into four groups: CON (basal diet with no additional DF), PF, OB, and MIX. After 56 days of feeding, we found that the growth performance of PF pigs was decreased (p < 0.05) compared with pigs in other groups. Results of real-time polymerase chain reaction and Western blot showed that the improvement of immune-related indexes (e.g., interleukin 10 [IL-10]) in OB and MIX pigs mainly presented in the ileum, whereas the improvement of intestinal barrier–related indexes (e.g., MUC1 and MUC2) mainly presented in the colon. Whether in the ileum or colon, such improvement of immune function may be dependent on NOD rather than TLR-associated pathways. Amplicon sequencing results showed that PF and MIX pigs shared a similar bacterial community, such as lower abundance of ileal Clostridiaceae and colonic Streptoccocus than that of CON pigs (p < 0.05). Our results indicate that OB and MIX, rather than PF, benefit the intestinal health in growing pigs, and multiple-sourced DF may reduce the adverse effect of single-soured DF on the growth performance and gut microbiota in pigs.

Influence of 8-week daily consumption of a new product combining green coffee hydroxycinnamates and beta-glucans on polyphenol bioavailability in subjects with overweight and obesity

Nutraceuticals based on plant extracts rich in polyphenols, as well as dietary fibres, are new means to fight overweight/obesity and associated diseases. However, to understand the potential effects of polyphenols on health it is critical to study their bioavailability and metabolic fate. Consumption of a green coffee phenolic extract (GCPE) in combination with oat beta-glucan (BG) could affect the pharmacokinetic profile of the main polyphenols present in coffee (hydroxycinnamates). Moreover, the regular intake of the combination could also induce changes. Nine overweight men and women consumed a novel nutraceutical product containing 300 mg of green coffee hydroxycinnamic acids and 2.5 g of BG twice a day for 8 weeks. A pharmacokinetic study was carried out in blood and urine samples taken before (baseline) and at week 8 after the nutraceutical intervention, collecting samples at different times in a 0-24 h interval. Faecal samples were also obtained at 0 and 24 h after the intake of the nutraceutical at baseline and week 8. Phenolic metabolites were analysed by LC-MS-QToF. Results showed that polyphenols were differentially absorbed and extensively metabolized throughout the gastrointestinal tract. An apparent reduction in the excretion of small intestinal metabolites was accompanied by a tendency to increase colonic metabolites after sustained intake (p = 0.052). In conclusion, continued consumption of the GCPE/BG nutraceutical appears to enhance the absorption of hydroxycinnamates by increasing the colonic bioavailability of their derived metabolites compared to baseline, although the regular intake of the nutraceutical did not modify the metabolite profile in any of the biological samples.

Lifestyle Modification in the Management of Metabolic Syndrome: Statement From Korean Society of CardioMetabolic Syndrome (KSCMS)

Metabolic syndrome (MetS) is highly prevalent and is associated with worse cardiovascular outcome. Lifestyle modification is the most effective way to reduce the incidence of cardiovascular complications caused by MetS. Here, we would like to review the effects and specific methods of the 6 lifestyle modifications (weight control, smoking cessation, alcohol drinking in moderation, diet control, exercise and physical activity, and cognitive behavioral therapy) and control of blood pressure, dyslipidemia, and blood sugar based on evidence in the management of MetS.

With the recent rapid increase in obesity worldwide, metabolic syndrome (MetS) has gained significant importance. MetS is a cluster of obesity-related cardiovascular risk factors including abdominal obesity, atherogenic dyslipidemia, high blood pressure and impaired glucose tolerance. MetS is highly prevalent and strongly associated with an increased risk of developing diabetes and cardiovascular disease, putting a great burden on human society. Therefore, it is very important to reduce MetS risk, which can improve patients’ cardiovascular prognosis. The primary and most effective strategy to control each component of MetS is lifestyle change such as losing body weight, keeping regular exercise, adopting a healthy diet, quitting smoking and alcohol drinking in moderation. Many studies have shown that lifestyle modification has improved all components of MetS, and reduces the incidence of diabetes and cardiovascular disease. Here, the Korean Society of CardioMetabolic Syndrome has summarized specific and practical methods of lifestyle modification in the management of MetS in the healthcare field.

Delving into the Role of Dietary Fiber in Gluten-Free Bread Formulations: Integrating Fundamental Rheological, Technological, Sensory, and Nutritional Aspects

The evidenced relevance of dietary fibers (DF) as functional ingredients shifted the research focus towards their incorporation into gluten-free (GF) bread, aiming to attain the DF contents required for the manifestation of health benefits. Numerous studies addressing the inclusion of DF from diverse sources rendered useful information regarding the role of DF in GF batter’s rheological properties, as well as the end product’s technological and nutritional qualities. The presented comprehensive review aspires to provide insight into the changes in fiber-enriched GF batter’s fundamental rheological properties, and technological, sensory, and nutritional GF bread quality from the insoluble and soluble DF (IDF and SDF) perspective. Different mechanisms for understanding IDF and SDF action on GF batter and bread were discussed. In general, IDF and SDF can enhance, but also diminish, the properties of GF batter and bread, depending on their addition level and the presence of available water in the GF system. However, it was seen that SDF addition provides a more homogenous GF batter structure, leading to bread with higher volumes and softer crumb, compared to IDF. The sensory properties of fiber-enriched GF breads were acceptable in most cases when the inclusion level was up to 7 g/100 g, regardless of the fiber type, enabling the labeling of the bread as a source of fiber.

Fructooligosaccharides on inflammation, immunomodulation, oxidative stress, and gut immune response: a systematic review

CONTEXT

Evidence shows that fructooligosaccharides (FOSs) can modulate inflammatory, oxidative, and immune activity in the gut, possibly leading to a systemic response, improving human health.

OBJECTIVE

To assess the present knowledge of the effects of FOSs on inflammation, immunomodulation, oxidative stress, and gut immune response.

DATA SOURCES

Studies published between December 2000 and January 2020 were systematically searched in four databases: MEDLINE, LILACS, Web of Science, and Scopus. After the screening of 1316 articles, 8 human studies and 20 animal models were included.

DATA EXTRACTION

Data were extracted separately by 2 reviewers. For each study, the design, population, exposures, main results, and conclusion were extracted. The research questions and the risk-of-bias information were also extracted. Additionally, the risk-of-bias were analyzed to guarantee the reliability of this review.

DATA ANALYSIS

A qualitative analysis revealed that FOSs can increase bifidobacteria counts and short-chain fatty acids in the gut, stimulate IgA secretion in the colon, and decrease proinflammatory cytokines, thus influencing metabolic diseases.

CONCLUSION

Studies suggest that FOS supplementation is positively associated with an anti-inflammatory and antioxidant effect, thus enhancing the gut immune system, which may be beneficial for the host's health.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration nos 42020209865 and 42020220369.

Association of maternal pre-pregnancy dietary intake with adverse maternal and neonatal outcomes: A systematic review and meta-analysis of prospective studies

This study aimed to summarize the evidence regarding the effects of dietary intake before conception on pregnancy outcomes by performing a systematic review and meta-analysis of prospective studies. Electronic databases were searched from inception up to August 2021. Overall, 65 studies involving 831 798 participants were included and 38 studies were quantitatively pooled. With regard to maternal outcomes, pre-pregnancy intake of fried food, fast food, red and processed meat, heme iron and a low-carbohydrate dietary pattern was positively associated with the risk of gestational diabetes mellitus (GDM) (all P < 0.05). However, a high dietary fiber intake and folic acid supplementation were negatively associated with GDM risk (both P < 0.05). With regard to neonatal outcomes, maternal caffeine intake before pregnancy significantly increased the risk of spontaneous abortion, while folic acid supplementation had protective effects on total adverse neonatal outcomes, preterm birth, and small-for-gestational age (SGA, all P < 0.05). However, no significant associations were found between adverse pregnancy outcomes (i.e., GDM and SGA) and the pre-pregnancy dietary intake of sugar-sweetened beverages, potato, fish, and carbohydrates and the Healthy Eating Index. Our study suggests that maintaining a healthy diet before conception has significant beneficial effects on pregnancy outcomes.Supplemental data for this article is available online at https://doi.org/10.1080/10408398.2021.1989658.

Therapeutic Potential of Various Plant-Based Fibers to Improve Energy Homeostasis via the Gut Microbiota

Obesity is due in part to increased consumption of a Western diet that is low in dietary fiber. Conversely, an increase in fiber supplementation to a diet can have various beneficial effects on metabolic homeostasis including weight loss and reduced adiposity. Fibers are extremely diverse in source and composition, such as high-amylose maize, β-glucan, wheat fiber, pectin, inulin-type fructans, and soluble corn fiber. Despite the heterogeneity of dietary fiber, most have been shown to play a role in alleviating obesity-related health issues, mainly by targeting and utilizing the properties of the gut microbiome. Reductions in body weight, adiposity, food intake, and markers of inflammation have all been reported with the consumption of various fibers, making them a promising treatment option for the obesity epidemic. This review will highlight the current findings on different plant-based fibers as a therapeutic dietary supplement to improve energy homeostasis via mechanisms of gut microbiota.

The effect of guar gum consumption on the lipid profile in type 2 diabetes mellitus: a systematic review and meta-analysis of randomized controlled trials

Dyslipidemia is a common encounter in type 2 diabetes mellitus (T2DM) and the current strategies to manage it are still suboptimal. Subsequently, identifying newer molecules with lipid-lowering effects is necessary. A great deal of attention has been given in recent years to fiber supplements, e.g., guar gum. Thus, we screened and evaluated the quality of the evidence regarding the benefits of guar gum supplementation in T2DM and conducted a meta-analysis to assess the effects of this compound on serum lipids in T2DM. We conducted a comprehensive search in PubMed/Medline, Web of Science, Scopus, Google Scholar and Embase, from the inception of these databases until January 2021. In total, 11 papers were included based on the eligible criteria in our meta-analysis. The meta-analysis of the eligible trials demonstrated a significant reduction of total cholesterol (TC) (WMD: -20.32 mg/dL, 95% CI: -27.02, -13.62, P < 0.001) and low-density lipoprotein cholesterol (LDL-C) (WMD: -14.52 mg/dL, 95% CI: -20.69, -8.35, P < 0.001) following guar gum supplementation in T2DM patients. The subgroup analysis based on the dosage (g/day) of this compound revealed that ≥20 g/day of guar gum led to a notable decrease in triglyceride (TG) levels (WMD: -12.55 mg/dL, 95% CI: -23.72, -1.37, P = 0.02) versus < 20 g/day (WMD: -1.84 mg/dL, 95% CI: -32.18, 28.49, P = 0.90). Guar gum supplementation had no effects on high-density lipoprotein cholesterol (HDL-C) (WMD: 0.66 mg/dL, 95% CI: -0.95, 2.28, P = 0.42). Guar gum consumption has lipid-lowering effects when administered to patients with type 2 diabetes mellitus and it is particularly able to reduce TC, LDL-C and TG levels. Further research is however needed to confirm our findings.

Complementary and Alternative Therapies for Weight Loss: A Narrative Review

Despite various strategies, overweight and obesity problems are still increasingly prevalent worldwide with serious health outcomes. Consequently, the continuous demand for more effective, safe and acceptable therapies for reducing body weight is also escalating—including complementary and alternative therapies (CATs). The aim of this review is to provide a summary of the most commonly- and recently-used CATs, with evaluation of their safety and efficacy for weight loss. Electronic scientific databases such as Scopus, PubMed and EBSCO Host were explored for articles that reported CATs for overweight and obesity treatment from 2015 to December 2019. Only systematic reviews, meta-analysis and randomized controlled trials (RCTs) published in English were included. Studies whereby CATs were not utilized for reducing body weight were excluded. Eight systematic reviews and meta-analyses and 11 additional RCTs with 765 participants (50.2% overweight and 49.8% obese) related to hypnotherapy, acupuncture and dietary supplements met the inclusion criteria. Their results suggested that spirulina, chitosan, probiotic, EPA + DHA, vitamin D, fiber, and herbal extract supplementation may all provide small reductions in body weight (ranging from 1-10 kg). Interestingly, hypnotherapy and acupuncture reported significantly greater reduction in body weight compared with placebo (p < 0.001 and p < 0.0001, respectively). Nonetheless, the evidence is still relatively limited and not encouraging to provide a definitive conclusion due to the methodological shortcomings and the presence of adverse events in chitosan and fiber supplementation. Hence, studies of this nature need to be further replicated and improved to corroborate the efficacy and safety of the CATs to combat weight issues.

Bistability in fatty-acid oxidation resulting from substrate inhibition

In this study we demonstrated through analytic considerations and numerical studies that the mitochondrial fatty-acid β-oxidation can exhibit bistable-hysteresis behavior. In an experimentally validated computational model we identified a specific region in the parameter space in which two distinct stable and one unstable steady state could be attained with different fluxes. The two stable states were referred to as low-flux (disease) and high-flux (healthy) state. By a modular kinetic approach we traced the origin and causes of the bistability back to the distributive kinetics and the conservation of CoA, in particular in the last rounds of the β-oxidation. We then extended the model to investigate various interventions that may confer health benefits by activating the pathway, including (i) activation of the last enzyme MCKAT via its endogenous regulator p46-SHC protein, (ii) addition of a thioesterase (an acyl-CoA hydrolysing enzyme) as a safety valve, and (iii) concomitant activation of a number of upstream and downstream enzymes by short-chain fatty-acids (SCFA), metabolites that are produced from nutritional fibers in the gut. A high concentration of SCFAs, thioesterase activity, and inhibition of the p46Shc protein led to a disappearance of the bistability, leaving only the high-flux state. A better understanding of the switch behavior of the mitochondrial fatty-acid oxidation process between a low- and a high-flux state may lead to dietary and pharmacological intervention in the treatment or prevention of obesity and or non-alcoholic fatty-liver disease.

High-Fat Diet with Lyophilized Acrocomia aculeata Pulp Increases High-Density Lipoprotein-Cholesterol Levels and Inhibits Adipocyte Hypertrophy in Mice

Obesity is a relevant health hazard characterized as a chronic noncommunicable disease, with severe comorbidities that cause mortality worldwide. Acrocomia aculeata is a Brazilian palm with edible fruits. Its pulp contains fibers, monounsaturated fatty acids (MUFAs), such as oleic acid and carotenoids. In this context, our study aimed to elucidate the protective effect of the lyophilized A. aculeata pulp added at the rates of 1%, 2%, and 4% to a high-fat (HF) diet (rich in saturated fats and cholesterol), for 90 days, in mice. The treatment with 4% pulp induced a significant increase in the biochemical parameters of serum cholesterol HDL-C (high-density lipoprotein) compared with the control. According to the evaluation of the epididymal tissue, the groups treated with A. aculeata pulp exhibited smaller fat deposits compared with the HF diet group. Therefore, we infer that the predominant components in A. aculeata, particularly fibers and MUFAs, promote beneficial effects on health parameters during simultaneous exposure to food rich in saturated fat and cholesterol, typical of the Western diet. This is the first study to correlate the presence of fatty acids from A. aculeata pulp in different proportions added in a HF diet with metabolic and histological parameters in Swiss mice.

Development and Validation of Test for "Leaky Gut" Small Intestinal and Colonic Permeability Using Sugars in Healthy Adults

BACKGROUND

Oral monosaccharides and disaccharides are used to measure in vivo human gut permeability through urinary excretion.

AIMS

The aims were as follows: (1) to obtain normative data on small intestinal and colonic permeability; (2) to assess variance on standard 16 g fiber diet performed twice; (3) to determine whether dietary fiber influences gut permeability measurements; and (4) to present pilot data using 2 selected probes in patients with diarrhea-predominant irritable bowel syndrome (IBS-D).

METHODS

Sixty healthy female and male adults, age 18-70 years, participated in 3 randomized studies (2 studies on 16.25 g and 1 study on 32.5 g fiber) in otherwise standardized diets. At each test, the following sugars were ingested: 12C-mannitol, 13C-mannitol, rhamnose (monosaccharides), sucralose, and lactulose (disaccharides). Standardized meals were administered from 24 hours before and during 24 hours post-sugars with 3 urine collections: 0-2, 2-8, and 8-24 hours. Sugars were measured using high-performance liquid chromatography-tandem mass spectrometry. Eighteen patients with IBS-D underwent 24-hour excretion studies after oral 13C-mannitol and lactulose.

RESULTS

Baseline sugars (>3-fold above lower limits of quantitation) were identified in the 3 studies: 12C-mannitol in all participants; sucralose in 4-8, and rhamnose in 1-3. Median excretions/24 h (percentage of administered dose) for 13C-mannitol, rhamnose, lactulose, and sucralose were ∼30%, ∼15%, 0.32%, and 2.3%, respectively. 13C-mannitol and rhamnose reflected mainly small intestinal permeability. Intraindividual saccharide excretions were consistent, with minor differences with 16.25 g vs 32.5 g fiber diets. Median interindividual coefficient of variation was 76.5% (10-90 percentile: 34.6-111.0). There were no significant effects of sex, age, or body mass index on permeability measurements in health. 13C-mannitol measurements are feasible in IBS-D.

CONCLUSIONS

Baseline 12C-mannitol excretion precludes its use; 13C-mannitol is the preferred probe for small intestinal permeability.

Effect of Mediterranean diet on liver enzymes: a systematic review and meta-analysis of randomised controlled trials

Elevated levels of liver enzymes are the main markers of liver dysfunction. Liver enzymes are the important indicators of non-alcoholic fatty liver disease (NAFLD) in the general population. Previous randomised clinical trials (RCT) investigated the effects of Mediterranean diet (MedDiet) as a plant-based diet on features of NAFLD like liver enzymes, but their results are contradictory. This study aimed to systematically review and meta-analyse RCT investigating the effect of MedDiet on liver enzymes. PubMed, Web of Science, Scopus and Google Scholar were searched until December 2020. A total of ten RCT (n 705 participants) evaluating the effect of MedDiet on liver enzymes including aspartate aminotransferase (AST), alanine transaminase (ALT) and γ-glutamyltransferase (GGT) were included. A random effects model was used to estimate the pooled effect size. To evaluate the heterogeneity among the included studies, the Cochran's Q-test and I-squared test were used. The MedDiet significantly reduced AST (weighted mean difference (WMD) = -0·38 IU/l; 95 % CI - 0·73, -0·03 IU/l; P = 0·03) and GGT (WMD = -0·16 IU/l; 95 % CI - 0·32, -0·006 IU/l; P = 0·04) but had no significant effect on ALT (WMD = -0·55 IU/l; 95 % CI - 1·25, 0·13 IU/l; P = 0·11). However, sensitivity analysis revealed that the overall effects of MedDiet on AST, GGT and ALT were significantly influenced by removing some studies. There was no publication bias based on Begg's and Egger's tests. Generally, MedDiet can improve liver enzymes. To better conclusion, further RCT investigating the effect of MedDiet on liver enzymes, especially in patients with NAFLD, are still required.

Dietary Fibre Modulates the Gut Microbiota

Dietary fibre has long been established as a nutritionally important, health-promoting food ingredient. Modern dietary practices have seen a significant reduction in fibre consumption compared with ancestral habits. This is related to the emergence of low-fibre “Western diets” associated with industrialised nations, and is linked to an increased prevalence of gut diseases such as inflammatory bowel disease, obesity, type II diabetes mellitus and metabolic syndrome. The characteristic metabolic parameters of these individuals include insulin resistance, high fasting and postprandial glucose, as well as high plasma cholesterol, low-density lipoprotein (LDL) and high-density lipoprotein (HDL). Gut microbial signatures are also altered significantly in these cohorts, suggesting a causative link between diet, microbes and disease. Dietary fibre consumption has been hypothesised to reverse these changes through microbial fermentation and the subsequent production of short-chain fatty acids (SCFA), which improves glucose and lipid parameters in individuals who harbour diseases associated with dysfunctional metabolism. This review article examines how different types of dietary fibre can differentially alter glucose and lipid metabolism through changes in gut microbiota composition and function.

Calcium Intake Is Inversely Related to Risk of Obesity among American Young Adults over a 30-Year Follow-Up

BACKGROUND

Calcium (Ca) is an essential nutrient that may play an important role in weight maintenance through its involvement in energy or lipid metabolism. However, little is known about the long-term associations of Ca intake with obesity risk.

OBJECTIVES

We aimed to prospectively examine the association between cumulative Ca intake and the incidence of obesity among American young adults over 30 y of follow-up.

METHODS

Participants were from the CARDIA (Coronary Artery Risk Development in Young Adults) study. A total of 4097 of 5115 black and white individuals aged 18-30 y at baseline in 1985-1986 were included in the current analysis. Dietary and supplemental Ca intake was assessed by the validated interview-based CARDIA diet history at baseline and exam years 7 and 20. Incident cases of obesity were identified when BMI was ≥30 kg/m2 for the first time since baseline. A survival analysis was performed using Cox proportional hazards regression models to estimate the HRs and corresponding 95% CIs for obesity incidence during follow-up.

RESULTS

During a 30-y follow-up (mean ± SD: 20 ± 10 y), 1675 participants developed obesity. Cumulative total Ca intake (dietary plus supplemental Ca) was inversely associated with incidence of obesity in multivariable-adjusted analysis [quintile (Q)5 (highest intake) compared with Q1 (lowest intake): HR: 0.68; 95% CI: 0.56, 0.82; P-trend < 0.01]. This inverse association persisted among Ca supplement users (Q5 compared with Q1: HR: 0.53; 95% CI: 0.40, 0.70; P-trend < 0.01), but was not seen among nonusers.

CONCLUSIONS

Following a cohort of Americans from young adulthood to midlife, an inverse association between calcium intake and obesity incidence was observed. Further studies are needed to confirm our findings.

Inulin Fermentable Fiber Ameliorates Type I Diabetes via IL22 and Short-Chain Fatty Acids in Experimental Models

BACKGROUND & AIMS

Nourishment of gut microbiota via consumption of fermentable fiber promotes gut health and guards against metabolic syndrome. In contrast, how dietary fiber impacts type 1 diabetes is less clear.

METHODS

To examine impact of dietary fibers on development of type 1 diabetes in the streptozotocin (STZ)-induced and spontaneous non-obese diabetes (NOD) models, mice were fed grain-based chow (GBC) or compositionally defined diets enriched with a fermentable fiber (inulin) or an insoluble fiber (cellulose). Spontaneous (NOD mice) or STZ-induced (wild-type mice) diabetes was monitored.

RESULTS

Relative to GBC, low-fiber diets exacerbated STZ-induced diabetes, whereas diets enriched with inulin, but not cellulose, strongly protected against or treated it. Inulin's restoration of glycemic control prevented loss of adipose depots, while reducing food and water consumption. Inulin normalized pancreatic function and markedly enhanced insulin sensitivity. Such amelioration of diabetes was associated with alterations in gut microbiota composition and was eliminated by antibiotic administration. Pharmacologic blockade of fermentation reduced inulin's beneficial impact on glycemic control, indicating a role for short-chain fatty acids (SCFA). Furthermore, inulin's microbiota-dependent anti-diabetic effect associated with SCFA-independent restoration of interleukin 22, which was necessary and sufficient to ameliorate STZ-induced diabetes. Inulin-enriched diets significantly delayed diabetes in NOD mice.

CONCLUSIONS

Fermentable fiber confers microbiota-dependent increases in SCFA and interleukin 22 that, together, may have potential to prevent and/or treat type 1 diabetes.

Dietary polyvinyl alcohol and alginate nanofibers ameliorate hyperglycemia by reducing insulin and glucose-metabolizing enzyme levels in rats with streptozotocin-induced diabetes

Background and Aim:

Dietary management and antidiabetic drugs are used as therapies for diabetic patients worldwide. Alginate nanofibers were developed as a digestible food product that provides sufficient calories. This study aimed to evaluate the effect of polyvinyl alcohol (PVA) and alginate nanofibers on weight gain, blood glucose levels, and insulin and other serum parameters in diabetic rats.

Materials and Methods:

A total of 24 male Wistar rats were divided into six groups: (C−) Control group, (C+) diabetic rats, (T1) diabetic rats + fasting treatment for 12 h, (T2) diabetic rats + nanofibers ad libitum, (T3) diabetic rats + metformin + nanofibers ad libitum, and (T4) diabetic rats + metformin. All groups were treated for 21 days. Weight gain was evaluated by comparing initial and final weights. Blood glucose levels were evaluated weekly. Serum parameters were also evaluated at the end of the study. All variables were analyzed statistically using analysis of variance followed by Tukey’s post hoc test (p<0.05).

Results:

The T2, T3, and T4 groups showed a significant increase in weight compared to that of the C+ and T1 groups. The T3 group had the lowest blood glucose level of all groups at the end of the study. In the serum evaluation, the T2 and T3 groups showed a significant decrease compared to the C+ group for the following variables: Alanine aminotransferase (ALT), alkaline phosphatase (ALP), gamma-glutamyltransferase (GGT), creatinine, tumor necrosis factor-alpha (TNF-α), and interleukin-1β (IL-1β). In contrast, the T2 group showed a significant decrease compared to the T3 group for aspartate aminotransferase and insulin levels.

Conclusion:

PVA and alginate nanofibers can modulate obesity, reduce blood glucose levels, and reduce serum levels of insulin, ALT, ALP, GGT, creatinine, TNF-α, and IL-1β in diabetic rats.

Role of Dietary Approaches to Stop Hypertension Diet in Risk of Metabolic Syndrome: Evidence from Observational and Interventional Studies

Background:

This systematic review was conducted to review the studies investigating the role of dietary approach to stop hypertension (DASH) diet in prevalence and progression of the metabolic syndrome (MetS) in children, adolescents, and adults.

Methods:

Electronic searches for included studies were performed in MEDLINE, SCOPUS, EMBASE, Cochrane Trial Register, and ISI Web of Science until 30 March 2020. Study selection, data extraction, and quality assessment were fulfilled independently by two reviewers using predefined criteria. Studies were included if they assessed the role of adherence to DASH diet in risk of incidence, prevalence, and development of MetS.

Results:

Twelve eligible studies (eight observational studies and four clinical trials) were identified. Despite methodological heterogeneity, limited statistical power, and the cross-sectional nature of most of observational studies, greater adherence to DASH diet was associated with reduced risk of MetS. However, results for change in metabolic characteristics based on dietary intervention with DASH diet in some interventional studies were somewhat controversial.

Conclusions:

The current study demonstrates that, based on observational studies, greater adherence to a DASH diet is inversely associated with MetS presence and progression. However, more interventional studies are needed in this regard to clarify the exact effect of DASH diet on MetS.

Personalized nutrition for colorectal cancer

The substantial burden of colorectal cancer and its increasing trend in young adults highlight the importance of dietary and lifestyle modifications for improved cancer prevention and survivorship. In this chapter, we review the cutting-edge evidence for the interplay between diet/lifestyle and the gut microbiota in the incidence and prognosis of colorectal cancer. We focus on factors for which there are data supporting their importance for the gut microbiota and colorectal cancer, including excess body weight, fiber, red and processed meat, and coffee. We discuss the potential precision nutrition approaches for modifying and exploiting the gut microbiota for improved cancer prevention and survivorship.

The association between plant-based diet indices and metabolic syndrome in Iranian older adults

BACKGROUND

We investigated the association between plant-based diets indices - an overall plant-based diet index; a healthful plant-based diet index; and an unhealthful plant-based diet index - and metabolic syndrome among Iranian older adults.

AIM

We aimed to examine the relationship between plant-based diet indices and metabolic syndrome.

METHODS

This cross-sectional study included 178 older adults (51 men and 127 women), with a mean age of 67.04 (60-83) who were referred to health centers in Tehran, Iran. Blood and urine samples were collected to measure serum total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and triglycerides. We created an overall plant-based diet index, healthful plant-based diet index, and unhealthful plant-based diet index from semi-quantitative food-frequency questionnaire data. Anthropometric measures were done.

RESULTS

Our crude model results showed that triglycerides, systolic and diastolic blood pressure, fasting blood sugar, high-density lipoprotein cholesterol, and waist circumference did not significantly differ between tertiles of plant-based diet index and healthful plant-based diet index; also triglycerides, systolic and diastolic blood pressure, fasting blood sugar, and waist circumference did not significantly differ between tertiles of unhealthful plant-based diet index, but high-density lipoprotein cholesterol significantly differed between tertiles of unhealthful plant-based diet index. After adjusting for confounders the results remained non-significant for plant-based diet index but high-density lipoprotein cholesterol was significant for healthful and unhealthful plant-based diet indices. There was also no significant association between plant-based diet index (OR: 1.11; 95% CI: 0.53-2.33), healthful plant-based diet index (OR: 0.81; 95% CI: 0.39-1.68), and unhealthful plant-based diet index (OR: 0.81; 95% CI: 0.38-1.72) with metabolic syndrome, even after adjustment for confounders.

CONCLUSIONS

Our findings showed that plant-based diets are not significantly associated with risk of metabolic syndrome in older adults. To confirm the veracity of these findings, more studies should be conducted.

Current Evidence Regarding Low-carb Diets for The Metabolic Control of Type-2 Diabetes

The management of diabetes requires a medical nutrition therapy as an essential part of this treatment. There should be no "one-size-fits-all" eating pattern for different patient´s profiles with diabetes. It is clinically complex to suggest an ideal percentage of calories from carbohydrates, protein and lipids recommended for all patients with diabetes. Among the eating patterns that have shown beneficial effects on metabolic control of patients with type 2 diabetes is the lowcarb diet, since the carbohydrate ingestion is viewed as the most important determinant of postprandial glucose and insulin response. In this context, theoretically, it could make sense to reduce the daily amount of carbohydrates ingested, to achieve lower levels of HbA1c. There could be risks associated to this approach. The adherence to a low-carb diet is here also discussed. This narrative review shows on the current evidence for answering these questions regarding low-carb diet as a possible alternative eating pattern for type 2 diabetes.

Effects of the dietary approach to stop hypertension (DASH) diet on blood pressure, blood glucose, and lipid profile in adolescents with hemophilia: A randomized clinical trial

Children with hemophilia are an enhanced risk of modifiable cardiovascular and metabolic abnormalities. There is currently no nutritional guideline to prevent or manage cardiometabolic risk factors in these patients. Therefore, the present study sought to investigate the effect of the Dietary Approaches to Stop Hypertension (DASH) diet on cardiovascular and metabolic risk factors among children with hemophilia. In this parallel randomized clinical trial, 40 children (all male) with hemophilia were randomly allocated to the DASH group (n = 20) or control group (n = 20) for 10 weeks. The intervention group received the DASH diet (50%-55% of energy from carbohydrate, 27%-30% of energy from fat and 16%-18% energy from protein), and the control group received nutritional recommendations based on healthy eating practices. Systolic blood pressure (SBP), diastolic blood pressure (DBP), fasting blood sugar (FBS), triglyceride (TG), total cholesterol (TC), low-density lipoprotein (LDL), and high-density lipoprotein (HDL) were measured at the beginning and end of the study. Serum vitamin C was measured as a biomarker of compliance with the DASH diet. Study was registered at IRCT.ir (IRCT20130903014551N6). A significant increase in serum vitamin C in the DASH diet group was observed compared to the control group (p = .001), indicating good compliance with the DASH diet. There was a significant reduction in SBP (-0.48 mmHg), DBP (-0.48 mmHg), FBS (-5.86 mg/dl), TC (-16.07 mg/dl), TG (-17.21 mg/dl), and LDL-C (-9.79 mg/dl), and a significant increase in HDL-C (3.39 mg/dl), in the DASH diet group compared with the control group. Adherence to the DASH diet in children with hemophilia yielded beneficial effects in blood pressure, lipid profiles, and FBS.