The Benefits of Dietary Fiber Intake on Reducing the Risk of Cancer: An Umbrella Review of Meta-analyses

Study of the acetylation-induced changes in the physicochemical and functional characteristics of insoluble dietary fiber from wheat bran

BACKGROUND

Wheat bran is rich in dietary fiber (DF), particularly insoluble dietary fiber (IDF). Although the benefits for human health following the consumption of these DFs have been documented, the lower water retention capacity (WRC) and other properties still limit the applications of DF. Therefore, the current research investigated the impact of acetylation on the changes in the corresponding physicochemical and functional properties of DF.

RESULTS

The current results indicated the acetylated group restricted the alignment of the molecular chains, which led to an increased amorphous phase in the fiber structure, followed by an enhanced thermal sensitivity and a reduced crystallinity as evidenced by X-ray diffraction (XRD). Moreover, the acetylation of the IDFs enhanced the cholesterol absorption capacity, but the corresponding antioxidant capacity and cation exchange capacity were reduced, which might be due to the partial loss of the phenolic compounds onto the polysaccharides during the modification. Interestingly, a lower degree of substitution (DS) of the IDF achieved from water-acetic anhydride modification led to a higher WRC and water swelling capacity (WSC). In contrast, a higher DS from acetic anhydride modification demonstrated a greatly improved in vitro hypoglycemic performance of the IDF, including α-amylase inhibitory activity and glucose dialysis retardation index (GDRI), compared to the other samples.

CONCLUSION

This study highlights a new approach to modify the functionality of IDFs via acetylation and the design of a novel IDF with hypoglycemic activity. © 2023 Society of Chemical Industry.

Properties and physiological effects of dietary fiber-enriched meat products: a review

Meat is a rich source of high biological proteins, vitamins, and minerals, but it is devoid of dietary fiber, an essential non-digestible carbohydrate component such as cellulose, hemicellulose, pectin, lignin, polysaccharides, and oligosaccharides. Dietary fibers are basically obtained from various cereals, legumes, fruits, vegetables, and their by-products and have numerous nutritional, functional, and health-benefiting properties. So, these fibers can be added to meat products to enhance their physicochemical properties, chemical composition, textural properties, and organoleptic qualities, as well as biological activities in controlling various lifestyle ailments such as obesity, certain cancers, type-II diabetes, cardiovascular diseases, and bowel disorders. These dietary fibers can also be used in meat products as an efficient extender/binder/filler to reduce the cost of production by increasing the cooking yield as well as by reducing the lean meat content and also as a fat replacer to minimize unhealthy fat content in the developed meat products. So, growing interest has been observed among meat processors, researchers, and scientists in exploring various new sources of dietary fibers for developing dietary fiber-enriched meat products in recent years. In the present review, various novel sources of dietary fibers, their physiological effects, their use in meat products, and their impact on various physicochemical, functional, and sensory attributes have been focused.

Role of the intestinal microbiota and diet in the onset and progression of colorectal and breast cancers and the interconnection between both types of tumours

Colorectal cancer (CRC) is among the leading causes of mortality in adults of both sexes worldwide, while breast cancer (BC) is among the leading causes of death in women. In addition to age, gender, and genetic predisposition, environmental and lifestyle factors exert a strong influence. Global diet, including alcohol consumption, is one of the most important modifiable factors affecting the risk of CRC and BC. Western dietary patterns promoting high intakes of xenobiotics from food processing and ethanol have been associated with increased cancer risk, whereas the Mediterranean diet, generally leading to a higher intake of polyphenols and fibre, has been associated with a protective effect. Gut dysbiosis is a common feature in CRC, where the usual microbiota is progressively replaced by opportunistic pathogens and the gut metabolome is altered. The relationship between microbiota and BC has been less studied. The estrobolome is the collection of genes from intestinal bacteria that can metabolize oestrogens. In a dysbiosis condition, microbial deconjugating enzymes can reactivate conjugated-deactivated oestrogens, increasing the risk of BC. In contrast, intestinal microorganisms can increase the biological activity and bioavailability of dietary phytochemicals through diverse microbial metabolic transformations, potentiating their anticancer activity. Members of the intestinal microbiota can increase the toxicity of xenobiotics through metabolic transformations. However, most of the microorganisms involved in diet-microbiota interactions remain poorly characterized. Here, we provide an overview of the associations between microbiota and diet in BC and CRC, considering the diverse types and heterogeneity of these cancers and their relationship between them and with gut microbiota.

Dietary Fibre Intake in Chile: 13 Years after the Last National Report

BACKGROUND

The objective is to provide updated data on the intake of total dietary fibre in the population residing in Chile and to identify food sources that contribute most to its intake, as well as its association with different sociodemographic and nutritional status-related determinants.

METHODS

In this descriptive cross-sectional study, a nationwide survey was applied to determine fibre intake using an instrument that has been previously validated in the resident population of Chile.

RESULTS

The sample consisted of a total of 1761 participants. Dietary fibre intake was 12.8 ± 7.1 g/day for the total population, and 90% of participants did not meet the recommendation, with no differences in consumption by sex, geographical area, and the urban/rural population. A lower consumption was found among participants with overweight and obesity. According to food groups, bread was the major contributor to fibre intake, providing 4.39 ± 3.05 g/day, followed by cereals (2.26 ± 2.80 g/day) and vegetables (1.85 ± 1.59 g/day).

CONCLUSIONS

90% of the population consume less fibre than recommended, and bread is the main food source; these data are critical for the development of strategies that are aimed at changing habits in order to improve diet quality.

Enhancing Health Benefits through Chlorophylls and Chlorophyll-Rich Agro-Food: A Comprehensive Review

Chlorophylls play a crucial role in photosynthesis and are abundantly found in green fruits and vegetables that form an integral part of our diet. Although limited, existing studies suggest that these photosynthetic pigments and their derivatives possess therapeutic properties. These bioactive molecules exhibit a wide range of beneficial effects, including antioxidant, antimutagenic, antigenotoxic, anti-cancer, and anti-obesogenic activities. However, it is unfortunate that leafy materials and fruit peels often go to waste in the food supply chain, contributing to the prevailing issue of food waste in modern societies. Nevertheless, these overlooked materials contain valuable bioactive compounds, including chlorophylls, which offer significant health benefits. Consequently, exploring the potential of these discarded resources, such as utilizing them as functional food ingredients, aligns with the principles of a circular economy and presents exciting opportunities for exploitation.

Effect of Insoluble Dietary Fiber Extracted from Feijoa (Acca sellowiana (O. Berg) Burret.) Supplementation on Physicochemical and Functional Properties of Wheat Bread

This study aimed to assess the effects of insoluble dietary fiber (IDF) from feijoa supplementation on the physicochemical and functional properties of wheat bread. The results showed that feijoa IDF (FJI) had the typical structures of hydrolysis fiber, polysaccharide functional groups, and crystal structure of cellulose. The gradual increase of FJI levels (from 2 to 8%) in wheat bread resulted in increased total DF, ash, and protein contents, accompanied by a reduction in moisture, carbohydrates, and energy value. The inclusion of FJI in the bread crumb caused a rise in both redness (a*) and yellowness (b*) values while decreasing the brightness (L*) relative to the control specimen. In addition, adding FJI up to 2% significantly increased total phenolic and flavonoid contents and antioxidant activity, as well as flavor score of supplemented bread samples, while additions above 2% resulted in undesirable taste and texture. FJI addition caused higher bile acid, NO2-, and cholesterol adsorption capacities. Moreover, FJI addition up to 4% significantly reduced glucose adsorption capacities at different in vitro starch digestion intervals. The findings revealed that FJI offers great potential as an ideal functional ingredient in food processing.

Cross-linking, carboxymethylation and hydroxypropylation treatment to sorghum dietary fiber: Effect on physicochemical, micro structural and thermal properties

The effect of cross-linking (CL), carboxymethylation (CM), and hydroxypropylation (HP) on the physicochemical, micro-structural, and thermal properties of sorghum dietary fiber (SODF) was studied. Results reflected that all three modifications significantly (p < 0.05) increased the water absorption capacity, swelling capacity, oil absorption capacity, and soluble dietary fiber content of SODF with CM being the most effective treatment. The CM significantly (p < 0.05) improved the solubility (9.9 %), whereas CL (4.65 %) and HP (2.79 %) significantly reduced the solubility of native SODF. The color analysis reflected the decrease in L* value after all modifications, indicating an increase in brown color of SODF. XRD analysis reflected an increase in crystallinity value (14.47 to 17.94 %) of SODF after modifications, resulting in increased thermal stability of modified SODF. The DSC results revealed the increased decomposition temperature of cross-linked and hydroxypropylated dietary fiber showing improved thermal stability of these types of modified fibers. The changes in thermal, physicochemical, and microstructural properties of SODF after modification could be ascribed to the changes in structure and chemical composition as reflected from SEM, XRD, and FTIR analysis.

Low carbohydrate high fat-diet in real life assessed by diet history interviews

BACKGROUND

Low carbohydrate high fat (LCHF) diet has been a popular low carbohydrate diet in Sweden for 15 years. Many people choose LCHF to lose weight or control diabetes, but there are concerns about the effect on long-term cardiovascular risks. There is little data on how a LCHF diet is composed in real-life. The aim of this study was to evaluate the dietary intake in a population with self-reported adherence to a LCHF diet.

METHODS

A cross-sectional study of 100 volunteers that considered themselves eating LCHF was conducted. Diet history interviews (DHIs) and physical activity monitoring for validation of the DHIs were performed.

RESULTS

The validation shows acceptable agreement of measured energy expenditure and reported energy intake. Median carbohydrate intake was 8.7 E% and 63% reported carbohydrate intake at potentially ketogenic levels. Median protein intake was 16.9 E%. The main source of energy was dietary fats (72.0 E%). Intake of saturated fat was 32 E% and cholesterol was 700 mg per day, both of which exceeded the recommended upper limits according to nutritional guidelines. Intake of dietary fiber was very low in our population. The use of dietary supplements was high, and it was more common to exceed the recommended upper limits of micronutrients than to have an intake below the lower limits.

CONCLUSIONS

Our study indicates that in a well-motivated population, a diet with very low carbohydrate intake can be sustained over time and without apparent risk of deficiencies. High intake of saturated fats and cholesterol as well as low intake of dietary fiber remains a concern.

Recommending ultra-processed oral nutrition supplements for unintentional weight loss: Are there risks?

Oral nutrition supplements (ONS) are widely recommended for the management of unintentional weight loss in patient populations, long-term care residents, and community-dwelling older adults. Most marketed ONS are ultra-processed, with precision nutrition and aseptic composition, as well as convenience and availability, driving their selection. However, therapeutic effectiveness is mixed and the potential health risks of consuming ultra-processed ONS long-term in lieu of less-processed foods have received little attention. A diverse and balanced microbiota supporting immunity and wellness is maintained by a diet rich in plant-sourced foods. The implications of ultra-processed ONS displacing plant-sourced foods, and specifically the potential for undesirable impacts on the gut microbiota, require consideration. Most ONS are either devoid of fiber or are supplemented with isolated or purified fibers that may contribute to adverse gastrointestinal symptoms and appetite suppression. In contrast, the diversity of microbial-available, nondigestible carbohydrates, together with the array of phytochemicals found in plant-sourced foods, support microbial diversity and its resiliency. This review outlines the clinical dilemma of recommending commercial ultra-processed ONS vs nutritionally adequate (eg, high-energy/high-protein) foods and beverages that contribute to diet quality, maintenance of a diverse and stable gut microbiota composition, and support nutrition status and health. Ultra-processed ONS may fall short of expected health benefits, and overreliance may potentially contribute to the risk for patient and older adult populations because of the displacement of a variety of healthful foods.

The effect of nutrition education for cancer prevention based on health belief model on nutrition knowledge, attitude, and practice of Iranian women

Background

In recent years, nutrition has received an increasingly important role in the etiology of cancer. Thus, public education about dietary factors associated with cancer risk or prevention could be an important intervention for cancer prevention, particularly in low- and middle-income countries where the burden of cancer is increasing rapidly and the access to care is limited. The age-standardized incidence of breast cancer was 35.8 among Iranian women in 2020. We aimed to study the effect of nutrition education on the knowledge, attitude, and practice of Iranian women towards dietary factors related to cancer.

Methods

In this interventional study, 229 women from public health centers were recruited and underwent three 75-min sessions of education based on the Health Belief Model (HBM). Participants were interviewed by trained interviewers using a validated and reproducible nutrition-related cancer prevention knowledge, attitude, and practice questionnaire (NUTCANKAP) questionnaire designed based on the HBM. Nutritional knowledge, attitude, and practice of participants were assessed through this questionnaire. Three 24-h dietary recalls (one weekend and two nonconsecutive weekdays) were also collected before and one month after the intervention.

Results

The mean age of the participants was 45.14 years, and the mean BMI was 27.2 kg/m². After the intervention, the participants had a higher intake of whole grain (p = 0.03) and a lower fat dairy (p = 0.009) and nuts (p = 0.04). However, the intake of high-fat dairy (p = 0.001) decreased after the intervention. We indicated significant differences in knowledge (p < 0.001) and nutritional practice scores (p = 0.01) after education. In addition, after the intervention, there were significant differences in the mean score of the HBM components, except for the perceived self-efficacy.

Conclusion

Participation in a nutrition education program positively impacted the knowledge and nutritional practices linked to cancer prevention.

Colon Cancer: From Epidemiology to Prevention

Colorectal cancer (CRC) is one of the most prevalent cancers affecting humans, with a complex genetic and environmental aetiology. Unlike cancers with known environmental, heritable, or sex-linked causes, sporadic CRC is hard to foresee and has no molecular biomarkers of risk in clinical use. One in twenty CRC cases presents with an established heritable component. The remaining cases are sporadic and associated with partially obscure genetic, epigenetic, regenerative, microbiological, dietary, and lifestyle factors. To tackle this complexity, we should improve the practice of colonoscopy, which is recommended uniformly beyond a certain age, to include an assessment of biomarkers indicative of individual CRC risk. Ideally, such biomarkers will be causal to the disease and potentially modifiable upon dietary or therapeutic interventions. Multi-omics analysis, including transcriptional, epigenetic as well as metagenomic, and metabolomic profiles, are urgently required to provide data for risk analyses. The aim of this article is to provide a perspective on the multifactorial derailment of homeostasis leading to the initiation of CRC, which may be explored via multi-omics and Gut-on-Chip analysis to identify much-needed predictive biomarkers.

The Impact of Cereal Grain Composition on the Health and Disease Outcomes

Whole grains are a pivotal food category for the human diet and represent an invaluable source of carbohydrates, proteins, fibers, phytocompunds, minerals, and vitamins. Many studies have shown that the consumption of whole grains is linked to a reduced risk of cancer, cardiovascular diseases, and type 2 diabetes and other chronic diseases. However, several of their positive health effects seem to disappear when grains are consumed in the refined form. Herein we review the available literature on whole grains with a focus on molecular composition and health benefits on many chronic diseases with the aim to offer an updated and pragmatic reference for physicians and nutrition professionals.

Cruciferous Vegetables and Their Bioactive Metabolites: from Prevention to Novel Therapies of Colorectal Cancer

The Brassicaceae family, known as cruciferous vegetables, includes many economically important species, mainly edible oil plants, vegetable species, spice plants, and feed plants. Cruciferous vegetables are foods rich in nutritive composition and are also a good source of dietary fiber. Besides, cruciferous vegetables contain various bioactive chemicals known as glucosinolates and S-methyl cysteine sulfoxide, including sulphur-containing cancer-protective chemicals. Numerous studies have reported that daily intake of sulphurous vegetables helps prevent cancer formation and reduces cancer incidence, especially in colorectal cancer, through various mechanisms. The potential mechanisms of these compounds in preventing cancer in experimental studies are as follows: protecting cells against DNA damage, inactivating carcinogenic substances, showing antiviral and antibacterial effects, triggering apoptosis in cells with disrupted structure, inhibiting tumour cell migration causing metastasis and the development of tumour-feeding vessels (angiogenesis). These beneficial anticancer effects of cruciferous vegetables are generally associated with glucosinolates in their composition and some secondary metabolites, as well as other phenolic compounds, seed oils, and dietary fiber in the literature. This review aims to examine to the roles of cruciferous vegetables and their important bioactive metabolites in the prevention and treatment of colorectal cancer.

The influences of acetylation, hydroxypropylation, enzymatic hydrolysis and crosslinking on improved adsorption capacities and in vitro hypoglycemic properties of millet bran dietary fibre

The effects of acetylation, hydroxypropylation, cellulase hydrolysis and crosslinking on adsorption capacities and in vitro hypoglycemic activities of millet bran dietary fibre (MBDF) were studied. The results demonstrated that both acetylation and hydroxypropylation improved water swelling ability of MBDF, and adsorption capacities of cholesterol, cholate and copper ion on MBDF. Acetylation and hydroxypropylation also enhanced α-glucosidase and α-amylase inhibition activities, glucose-binding ability and glucose diffusion retardation index (GDRI) of MBDF. Acetylated MBDF showed the highest cholate (77.31 mg/g) and cholesterol (13.97 mg/g) adsorption capacities. The crosslinking improved adsorption of cholate, cholesterol, copper ion (25.64 mg/g) and nitrite ion (181.59 μg/g) on MBDF; but reduced α-amylase inhibition activity (p < 0.05). Moreover, cellulase hydrolyzed MBDF exhibited the highest GDRI (39.60%) and α-amylase inhibition activity (34.53%), but the lowest oil and cholate adsorption capacities. The results suggest that the modified MBDFs can be used as an ingredient of hypoglycemic foods.

Dietary Fiber Intake and Risk of Pancreatic Cancer: Systematic Review and Meta-Analysis of Observational Studies

The burden of pancreatic cancer varies greatly across countries, with the number of deaths, incident cases, and disability-adjusted life years more than doubling in recent years, and with high-income countries having the highest incidence and mortality rates. We conducted this systematic review with meta-analysis with the goal of summarizing the current evidence on dietary fiber intake and its role in reducing the risk of pancreatic cancer, given the importance of identifying risk factors. This systematic review followed the guidelines of the Cochrane Collaboration and the Meta-analysis of Observational Studies in Epidemiology and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020. The structured literature search was conducted on PubMed/Medline and Scopus, combining free text words and medical subject headings. Our review contained 18 records at the end of the process. Our results show that dietary fiber intake reduces the risk of pancreatic cancer. When the analysis was differentiated according to the type of fiber considered, sub-grouped by gender (reduction of around 60% among women), and when case-control studies were conducted, the strength of the association increased. Clinicians and policymakers should improve interventions to raise the population's awareness regarding the consumption of high-fiber diets, both in practice and in terms of public health policy.

Effect of four modification methods on adsorption capacities and in vitro hypoglycemic properties of millet bran dietary fibre

To improve the adsorption capacities and hypoglycemic properties of millet bran dietary fibre (MBDF), four methods including acrylate-grafting, carboxymethylation, heat assisted with cellulase hydrolysis, and enzymatic hydrolysis combined with acrylate-grafting were used. The results demonstrated that all carboxymethylation, acrylate-grafting, and enzymatic hydrolysis combined with acrylate-grafting improved soluble dietary fibre content, water swelling ability and α-amylase-inhibition activity of MBDF. They also increased oil, cholesterol, sodium cholate, copper ion and nitrite ion adsorption capacities of MBDF. But carboxymethylation, acrylate-grafting and enzymatic hydrolysis combined with acrylate-grafting decreased polyphenol content, glucose-binding ability and glucose dialysis retardation index of MBDF (p < 0.05). The heat assisted with cellulase hydrolysis increased soluble dietary fibre content, polyphenol content, sodium cholate-adsorption capacity, and hypoglycemic properties of MBDF including glucose-binding ability, glucose dialysis retardation index and α-amylase-inhibition activity; but reduced adsorption capacity of MBDF on cholesterol and copper ion (p < 0.05). Changes in structure of MBDF caused by these modification methods were proved by the results of scanning electron microscopy and Fourier-transformed infrared spectroscopy analysis. These results highlight potential applications of these modified MBDFs as ingredients of hypolipidemic and hypoglycemic foods, or scavenger of nitrite and copper ion.

The association of dietary β-carotene and vitamin A intake on the risk of esophageal cancer: a meta-analysis

BACKGROUND AND PURPOSE

dietary β-carotene and vitamin A intake have shown some potential effect in the development of esophageal cancer. This meta-analysis was performed to investigate the association of β-carotene and vitamin A intake on the risk of esophageal cancer.

METHODS

the PubMed, Embase, Web of Science and Wanfang Med online databases were systematically searched to collect the relevant articles regarding the impact of β-carotene and vitamin A intake on esophageal cancer risk. Pooled odds ratios (OR) with 95 % confidence intervals (CI) were combined using the Review Manager Version 5.3 software.

RESULTS

this meta-analysis included 14 articles. The highest category of β-carotene intake may significantly reduce the risk of esophageal cancer compared with the lowest category (OR = 0.62, 95 % CI = 0.50-0.77). Similar significant results were found in American and European populations but not in other populations with β-carotene intake. An inverse association was found between vitamin A intake and esophageal cancer risk (OR = 0.79, 95 % CI = 0.63-0.99). No potential publication bias was detected.

CONCLUSIONS

our study suggested that dietary β-carotene and vitamin A intake may reduce the risk of esophageal cancer. More relevant studies are needed to further explore this association, as there were some limitations in our analysis.

Design of enzyme-responsive short-chain fatty acid-based self-assembling drug for alleviation of type 2 diabetes mellitus

Short-chain fatty acids (SCFAs), such as propionic and butyric acids have been touted as potential therapeutic interventions that can ameliorate diabetic pathogenesis. However, SCFAs are low-molecular-weight (LMW) compounds that have limited clinical use due to unfavorable pharmacokinetics, off-target effects, poor palatability and unpleasant odor. Hence, to improve the therapeutic utilization of SCFAs, the enzyme metabolizable block copolymers, [poly(ethylene glycol)-b-poly(vinyl ester)s], possessing propionate and butyrate esters were synthesized, which formed stable nanoparticles by self-assembling under physiological conditions. In this study, the therapeutic efficacy of propionic acid- and butyric acid-based self-assembling nanoparticles (PNP/BNP) was evaluated in a mouse model of type 2 diabetes mellitus through ad libitum drinking. The conventional antidiabetic drug, exenatide- and BNP-treated mice showed the highest glucose tolerance, whereas LMW SCFAs remained ineffective in normalizing glucose homeostasis. The better efficacy of BNP over the LMW SCFAs was attributable to (i) higher consumption of BNP than the LMW SCFAs by the mice (good palatability and odorless), (ii) prolonged residence time of BNP (48 h) in the gastro-intestinal tract (muco-adhesion) contributing to intestinal enzyme-mediated sustained release of butyric acid, and (iii) negligible off-target effects (no abrupt rise in the bloodstream). The aforementioned data suggest that SCFA-based nanoparticles are more potential therapeutic interventions than LMW SCFAs for metabolic diseases such as diabetes.

Dietary carbohydrate intake and the risk of esophageal cancer: a meta-analysis

BACKGROUND

Previous studies had been published to explore the association about carbohydrate intake on esophageal cancer risk, with inconsistent results. This meta-analysis aimed to assess the association between dietary carbohydrate intake and the risk of esophageal cancer.

METHODS

Suitable studies were carefully searched with the databases of PubMed, Embase, the Cochrane Library, and Wanfang Database. A random-effects model was used for combined odds ratio (OR) and 95% confidence interval (CI). Stata software 14.0 was adopted for the analysis.

RESULTS

At the end, 13 publications were included in our study. Pooled results suggested that highest category versus lowest category of carbohydrate intake could reduce the risk of esophageal cancer (summarized OR = 0.627, 95% CI = 0.505-0.778, I2 = 59.9%, Pfor heterogeneity = 0.001). The results for carbohydrate intake on the risk of esophageal adenocarcinoma (summarized OR = 0.569, 95% CI = 0.417-0.777) and esophageal squamous cell carcinoma (summarized OR = 0.665, 95% CI = 0.453-0.975) were consistent with the overall result. A positive association was found in European, Asian, North American populations, instead of South American populations.

CONCLUSIONS

In conclusions, dietary carbohydrate intake may have a protective effect against the risk of esophageal cancer.

Tostes M, Costa NM. The Potential Prebiotic Effects of Yacon (Smallanthus sonchifolius) in Colorectal Cancer

Background:

Colorectal cancer is caused by genetic predisposition and lifestyle risk factors and is associated with altered homeostasis of the intestinal microbiota. Evidence suggests that chronic infection and inflammation contribute to carcinogenic mutagenesis and promote cancer initiation and progression. Food components with prebiotic properties, such as fructooligosaccharides (FOS), promote intestinal integrity and health benefits. Yacon (Smallanthus sonchifolius) is an abundant source of FOS, which are fermented by beneficial bacteria, improving the intestinal environment affected by colorectal cancer.

Objective:

In the current review, the aim was to discuss colorectal cancer and its inflammatory process of development. Also, some general aspects concerning yacon roots and its prebiotic properties are described. Finely, the beneficial effects of yacon to reduce intestinal parameters altered due to colorectal cancer are summarized.

Conclusion:

It was verified that yacon might improve immunological parameters, intestinal barrier, intestinal microbiota, and inflammation in induced colorectal cancer in animals, especially. Researches with humans must be further investigated to prove these positive effects.

Anticancer and Immunomodulatory Benefits of Taro (Colocasia esculenta) Corms, an Underexploited Tuber Crop

Taro corms contain valuable bioactive molecules effective against cancer and cancer-related risk factors, such as carcinogens and biological agents, several pathophysiological conditions, including oxidative stress and inflammation, while controlling metabolic dysfunctions and boosting the immunological response. Such broad effects are achieved by the taro health-influencing compounds displaying antitumoral, antimutagenic, immunomodulatory, anti-inflammatory, antioxidant, anti-hyperglycemic, and anti-hyperlipidemic activities. Taro bioactivities are attributed to the combination of tarin, taro-4-I polysaccharide, taro polysaccharides 1 and 2 (TPS-1 and TPS-2), A-1/B-2 α-amylase inhibitors, monogalactosyldiacylglycerols (MGDGs), digalactosyldiacylglycerols (DGDGs), polyphenols, and nonphenolic antioxidants. Most of these compounds have been purified and successfully challenged in vitro and in vivo, proving their involvement in the aforementioned activities. Although these health-promoting effects have been recognized since ancient times, as well as other valuable features of taro for food profit, such as hypo-allergenicity, gluten-free, and carbohydrates with medium-glycemic index, taro crop remains underexploited. The popularization of taro intake should be considered a dietary intervention strategy to be applied to improve the overall health status of the organism and as supportive therapy to manage tumorigenesis.

Effectiveness of Fiber Supplementation for Constipation, Weight Loss, and Supporting Gastrointestinal Function: A Narrative Review of Meta-Analyses

Objective

The purpose of this narrative review is to determine whether published meta-analyses support the use of fiber supplementation in the treatment of constipation, weight loss, and dietary support for gastrointestinal disorders such as irritable bowel syndrome (IBS) and inflammatory bowel disease.

Methods

A PubMed search from January 1, 1980, to July 31, 2019, was conducted with the following search strategy: (fiber OR fibre) AND (meta-analysis OR systematic review) AND (constipation OR body weight OR obesity OR irritable bowel syndrome OR inflammatory bowel disease). Meta-analyses that provided quantitative statistical analysis with a measured effect size were retrieved and accepted into this review. The following was extracted and entered into an Excel spreadsheet: number of publications included in the meta-analysis, number of total participants, fiber type and daily dose, pooled treatment effects for clinical endpoints, or summary relative risks.

Results

Eighteen meta-analyses support dietary fiber supplementation for patients with constipation, weight loss, and IBS, but the significant heterogeneity and publication bias undermine the support for using dietary fiber supplementation in these conditions.

Conclusion

This narrative review of meta-analyses finds some benefits for recommending fiber supplementation to patients with constipation, obesity, and IBS, but significant heterogeneity and publication bias undermine this support.

Dietary Fiber and Survival in Women with Breast Cancer: A Dose-Response Meta-Analysis of Prospective Cohort Studies

We aimed to investigate the association of dietary fiber consumption with mortality risk in women with breast cancer. A systematic search was undertaken in PubMed, Scopus, and ISI Web of Science till March 2020 to find cohort studies investigating the association of dietary fiber consumption with mortality risk in women with breast cancer. A random-effects model was used to combine study-specific results. The quality of evidence was rated by NutriGrade score. Seven prospective cohort studies with 1,426 cases of all-cause mortality and 679 cases of breast cancer-specific mortality among 11,295 patients with breast cancer were included. The relative risks for the highest compared to the lowest category of dietary fiber consumption were 0.63 (95%CI: 0.52, 0.77; I² = 0%, n = 5) for all-cause mortality, and 0.72 (95%CI: 0.54, 0.96; I² = 0%, n = 5) for breast cancer-specific mortality. There was a strong linear association between fiber intake and all-cause mortality risk. The quality of evidence was rated moderate for all-cause mortality, and low for breast cancer-specific mortality. Higher dietary fiber consumption may improve survival in patients with breast cancer. More research is needed to confirm the present results, considering types of fiber consumed and tumor estrogen receptor status.

Associations between nutritional factors and KRAS mutations in colorectal cancer: a systematic review

BACKGROUND

Between 30 and 50% of colon tumors have mutations in the Kirsten-ras (KRAS) gene, which have a large nutritional attributable risk. Despite its high frequency in colorectal cancer (CRC), data to support specific associations between KRAS mutations in CRC and diet are sparse. Here, we conducted a systematic review to summarize the current epidemiological evidence on the association between various dietary factors and KRAS mutations.

METHODS

PubMed, Science Direct, and Cochrane databases were searched for relevant studies published until December 31, 2019, using inclusion and exclusion criteria in accordance with PRISMA guidelines. We analyzed the studies to find associations between nutritional factors and CRC tumors with KRAS mutations in humans.

RESULTS

We identified 28 relevant studies to include in this systematic review. In-depth analyses showed unclear associations between nutritional factors and KRAS mutations in CRC. Most epidemiological studies in the same nutrient or food often reported conflicting and/or inconclusive findings, whereas for some dietary factors, the results were homogeneous.

CONCLUSIONS

Further research using a more robust prospective cohort study is needed to lend more credence to the epidemiological associations found between KRAS mutations and dietary factors.

PATTERNS OF FIBER INTAKE AMONG BRAZILIAN ADULTS: PERCEPTIONS FROM AN ONLINE NATIONWIDE SURVEY

BACKGROUND

Adequate fiber intake is associated with digestive health and reduced risk of several noncommunicable diseases and is recognized as essential for human health (World Health Organization, 2003). The World Health Organization (WHO) recommends a daily fiber consumption of ≥25 g, but previous studies observed a fiber intake in Brazil lower than recommended.

OBJECTIVE

We aimed to describe fiber intake among adults in Brazil and also respondents' knowledge and perceptions about their fiber intake.

METHODS

National online survey with community-dwelling Brazilian individuals. The survey was conducted during September 2018, using an online platform with closed-ended questions. A representative sample of Brazilian internet users stratified by sex, age, socioeconomic status and geographic region was adopted. Sample size was calculated using a 2% error margin and 95% confidence interval (n=2,000). Data was descriptively analyzed using measures of frequency, central tendency and dispersion.

RESULTS

Sample included 2,000 individuals who were well-balanced in terms of sex (51.2% female), with mean age of 35.9 years (most represented age group was 35-54 years, 39.6%) and from all country geographic regions (49.4% from Southeast). A total of 69.7% of them consider their usual diet as healthy and 78.4% reported consuming fibers regularly. Fibers from natural sources are consumed at least once a day by 69.5% of the sample, while daily fiber supplements were reported by 29.9%. Absence of regular fiber intake was reported by 21.7% of respondents and the most common reason was "lack of knowledge about fiber sources" (39.3%). When informed about the food sources of each type of fiber (soluble and insoluble) and asked about the regular intake, only 2.5% answered that they do not consume any of them regularly (as opposed to 21.7% before receiving information about specific fiber sources).

CONCLUSION

Our findings indicate that fiber intake in Brazil is probably insufficient with a high proportion of individuals reporting irregular or absent ingestion of fiber sources in their daily lives. Lack of knowledge about fiber sources and fiber types seems to play a role in this inadequate intake, highlighting the need for nutritional education to achieve healthy dietary patterns in the country.

The association between dietary protein intake and esophageal cancer risk: a meta-analysis

Several papers studied dietary protein intake as a potential influence factor for esophageal cancer, but their findings were inconsistent. Thus, this meta-analysis was performed to identify the effect of protein intake on esophageal cancer risk. Potential case–control studies or cohort studies from the databases of Embase, Web of Science and PubMed were searched. The strength of association was quantified by pooling odds ratio (OR) and 95% confidence interval (CI). In total, 11 articles involving 2537 cases and 11432 participants were included in this meta-analysis. As a result, dietary protein intake had non-significant association on esophageal cancer risk overall (pooled OR = 1.11, 95% CI = 0.88–1.40). Meanwhile, we obtained consistent results in the subgroups analyses by study design, protein type, geographic locations and number of cases. Interestingly, dietary protein intake could significantly increase the risk of esophageal squamous cell carcinoma (pooled OR = 1.29, 95% CI = 1.02–1.62), instead of other disease type. To sum up, dietary protein intake had no significant association with esophageal cancer risk in the overall analysis; but, protein intake may be associated with the risk of esophageal squamous cell carcinoma. While some limitations existed in the present paper, more studies with large sample size are warranted to further confirm this result.

Effect of dietary cholesterol intake on the risk of esophageal cancer: a meta-analysis

Objective

This systematic review aimed to explore the potential association between dietary cholesterol intake and esophageal cancer risk.

Methods

A literature search was conducted using PubMed, Embase, and Web of Science databases from inception to March 2019 according to specific inclusion and exclusion criteria. Pooled estimates with odds ratio (ORs) and 95% confidence intervals (CIs) were obtained using random effects models.

Results

Nine articles of 12 independent studies were included in the final meta-analysis. Pooled analysis suggested that dietary cholesterol intake may increase the risk of esophageal cancer (summarized OR = 1.424, 95% CI = 1.191–1.704). Consistent results were found in American (summarized OR = 1.410, 95% CI = 1.130–1.758) and European populations (summarized OR = 1.556, 95% CI = 1.021–2.373). Subgroup analysis by disease type showed that dietary cholesterol intake had a significant association with the development of esophageal adenocarcinoma and esophageal squamous cell carcinoma.

Conclusion

Our findings indicated that dietary cholesterol intake could significantly increase the risk of developing esophageal cancer in both European and American populations. Further high-quality studies are necessary to confirm the effects of cholesterol intake.

How Important are Cereals and Cereal Products in the Average Polish Diet?

The main aim of this study was to identify the food sources of energy and 28 nutrients from cereals and cereal products in the average Polish diet based on data from a nationally representative sample of the Polish population attending in 2016 Household Budget Survey (i.e., 36,886 households). The contribution of energy and nutrients from cereals and cereal products were compared with reference values. The detailded analysis included five main groups and nine sub-groups of cereal food category. Our findings indicated that cereals and cereal products contributed 30.4% of total dietary energy supply, providing a significant percentage of six nutrients to the average Polish diet (i.e., 64.1% of manganese, 51% of carbohydrates, 48.5% of dietary fibre, 34.1% of iron, 33.6% of folate, and 31.3% of copper). Supply at the level of 20⁻30% was observed for protein, thiamin, phosphorus and zinc, and at 10⁻20% for polyunsaturated fatty acids (PUFA), sodium, potassium, calcium, riboflavin, niacin, and vitamin B6. For other nutrients i.e., total fat, saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), cholesterol, iodine, vitamins: A, D, B12, and C, the share of cereals and cereal products contribution was below 10%. Cereals and cereal products were the major food category in meeting the reference values for the Polish population in case of manganese, carbohydrates (approximately100%), and sodium (50%). The reference values was reached at the level of 30⁻40% for dietary fibre, protein, iron, copper, zinc, phosphorus and thiamin, and 20⁻30% for energy, magnesium, folate, niacin, riboflavin, vitamins B6 and E. For such nutrients as total fat, SFA, and potassium, the fulfillment of the reference values amounted to 10⁻20%. Our results document the importance of cereals and cereal products in the Polish diet, which should be emphasized from a nutritional and health point of view.