Role Of Dietary Fiber Research Articles

Abstract LB-186: Fiber intake modulates the effect of alcohol on breast cancer

Abstract Alcohol intake has been related to an increase risk of breast cancer while dietary fiber intake has been inversely correlated to breast cancer risk. A beneficial effect of fiber on ethanol carcinogenesis through their impact on estrogen levels is still controversial. The purpose of this study is to investigate the role of dietary fiber as potential modifying factors of the association of alcohol to breast cancer using data from the European Prospective Investigation into Cancer and Nutrition (EPIC) study. A prospective observational study of 334,850 women aged 35-70 years at baseline enrolled in the ten countries of the EPIC study and followed up for 11.0 years on average was conducted. Information on fiber and alcohol intake at baseline and average lifetime alcohol intake were calculated from country-specific dietary and lifestyle questionnaires. Hazard ratios (HR) and 95% confidence intervals (CI) of developing invasive breast cancer according to different levels of alcohol and fiber intake were calculated. During 3,670,439 person-years, 11,576 incident breast cancer cases were diagnosed. Among women with low intake of fiber (<18.5 g/day), the risk of breast cancer per 10g/day of alcohol intake was 1.057 (1.032;1.082) while among women with high intake of fiber (>24.2 g/day) the risk of breast cancer was 1.012 (0.983;0.1.04) (Test for interaction p = 0.01). This modulating effect was stronger for fiber from vegetables and for estrogen positive tumors. Our results suggest that fiber intake may modulate the positive association of alcohol intake to breast cancer risk. Women should be advised to control their alcohol intake, and increase their intake of fiber. Citation Format: Isabelle Romieu. Fiber intake modulates the effect of alcohol on breast cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr LB-186. doi:10.1158/1538-7445.AM2015-LB-186

Dietary fibre and health in children and adolescents.

The role of dietary fibre in promoting sustained health has been studied for several decades and in adults there is good evidence that diets rich in high-fibre foods reduce the risk of chronic diseases, including CVD and cancer. Research in this area, however, has been hampered by uncertainties about the definition of dietary fibre which has resulted in many studies measuring fibre in different ways. There is also a wide range of properties and actions of different fibres in the human body, depending on their solubility, viscosity and fermentability by the colonic microbiota. This review considers the epidemiological evidence for dietary fibre and health in children and the current dietary recommendations and measured intakes in several countries using national surveys. In children and adolescents, there is a particular lack of relevant research on which to formulate appropriate dietary fibre recommendations and these are often based on extrapolation from adult data. However, children are not little adults and have differing physiology and nutritional needs as they grow. The dietary recommendations in different countries are based on varying premises and daily amounts. Intakes vary from country to country and on the whole do not meet recommendations. Much more research is needed in children to fully understand the impact of dietary fibre on growth and health in the young to allow more appropriate recommendations to be made.

The role of dietary fibre in inflammatory bowel disease.

The aetiology of inflammatory bowel diseases (IBD), which are primarily Crohn's disease and ulcerative colitis, still remains unclear, while the incidence of IBD is constantly increasing, especially in the industrialised countries. Among genetic, environmental, and immunological factors, changes in the composition of the intestinal microflora and diet are indicated as very important in initiating and sustaining inflammation in patients with IBD. Above all nutrients dietary fibre is an especially important component of diet in the context of IBD. A potentially protective effect of high-fibre diet on intestinal disorders was described as early as in 1973. Several trials performed in animal models of IBD and human studies have reported that supplementation of some types of dietary fibre can prolong remission and reduce lesions of the intestinal mucosa during the course of the disease. This paper presents the current state of knowledge on the effects of dietary fibre in IBD.

Control of appetite and energy intake by SCFA: what are the potential underlying mechanisms?

In recent years, there has been a renewed interest in the role of dietary fibre in obesity management. Much of this interest stems from animal and human studies which suggest that an increased intake of fermentable fibre can suppress appetite and improve weight management. A growing number of reports have demonstrated that the principal products of colonic fermentation of dietary fibre, SCFA, contribute to energy homeostasis via effects on multiple cellular metabolic pathways and receptor-mediated mechanisms. In particular, over the past decade it has been identified that a widespread receptor system exists for SCFA. These G-protein-coupled receptors, free fatty acid receptor (FFAR) 2 and FFAR3 are expressed in numerous tissue sites, including the gut epithelium and adipose tissue. Investigations using FFAR2- or FFAR3-deficient animal models suggest that SCFA-mediated stimulation of these receptors enhances the release of the anorectic hormones peptide tyrosine tyrosine and glucagon-like peptide-1 from colonic L cells and leptin from adipocytes. In addition, the SCFA acetate has recently been shown to have a direct role in central appetite regulation. Furthermore, the SCFA propionate is a known precursor for hepatic glucose production, which has been reported to suppress feeding behaviour in ruminant studies through the stimulation of hepatic vagal afferents. The present review therefore proposes that an elevated colonic production of SCFA could stimulate numerous hormonal and neural signals at different organ and tissue sites that would cumulatively suppress short-term appetite and energy intake.

Gut bacteria and the development of diet-induced obesity: The role of dietary fiber and short-chain fatty acids

Gut bacteria and the development of diet-induced obesity: The role of dietary fiber and short-chain fatty acids

Nutritional Regurgitations—Spiraling, Rhyming, Repeating

In nutritional science, the same issues often are revisited again and again, but from deepened foundations of knowledge and the new perspectives they bring. Examples discussed include the ongoing debates surrounding the roles of dietary fiber, phytic and oxalic acids, and fish oils and omega 3 fatty acids in human nutrition. Despite the accomplishments made possible by science, consumers often view science and scientists with skepticism. Overwhelmed by contradictory and inconclusive information, consumers are increasingly demanding certainty from the nutrition, health, and physiology sciences. In the modern information age, professional and industry associations need to invest far more in establishing a credible presence in electronic and social media platforms.

My medical practice: mentors and perspectives

I was only the second of my family to go to university. Almost from infancy my mother would describe me as ‘my son, the doctor to be’. My brother and I went as choral scholars to Southwell Minster choir school, perfect Anthony Trollope country.1 Sport, especially long distance running and science proved to be my lifelong interests, leading to Edinburgh University and the exciting life of medicine. A bonus in our first term was to meet my future wife Jenny, companion, friend, Consultant Psychiatrist and mother of our four children. Together we joined a medical community who still meet regularly as friends and to help and support each other. After graduating I studied biochemistry, before training as a physician in the Royal Infirmary of Edinburgh. I was appointed as Consultant Gastroenterologist at the Western General Hospital, Edinburgh in 1969. The appointment was a mix of academia and clinical practice. The prime project was to study the physiology and role of dietary fibre in the aetiology, prevention and treatment of a long list of diseases. A big, even improbable task.2 So what was my perception of a model Physician? I was fortunate to work for such first rate chiefs in the Royal Infirmary of Edinburgh, Ranald Murray-Lyon and Professor Ronald Girdwood. However, the ideal for me was Sir John Halliday …

In vitro Effect of Aqueous Extract of Fresh Leaves of Abroma augusta L on the Diffusion of Glucose

There have been a number of reports concerning the role of dietary fiber in hampering the diffusion of glucose and lowering the postprandial serum glucose. The present study investigates the effect of viscous aqueous leaf extract of Abroma augusta L (Family: Sterculiaceae, Bengali name: Ulatkambal, English name: Devil's cotton, DC) on the diffusion of glucose in vitro. Different mixtures were prepared using varying concentrations of sodium carboxymethylcellulose (Na-CMC) and aqueous extract of A. augusta with a fixed concentration of glucose. The diffusion of glucose from these systems into the outer medium through the ultra-fine membrane was measured. The results showed that both Na-CMC and aqueous extract of ulatkambal significantly (p<0.05) reduced the diffusion of glucose compared to control in a concentration-dependent manner. The result of this study suggested that dietary fiber present in the aqueous leaf extract of A. augusta may be potentially effective in the management of type 2 diabetes mellitus by reducing post-prandial glucose absorption from the gastrointestinal tract. DOI: http://dx.doi.org/10.3329/bpj.v16i1.14486 Bangladesh Pharmaceutical Journal 16(1): 21-26, 2013

광주·전남 일부지역 초등학생의 채소류 섭취에 대한 인식

The purpose of this study was to analyze the dietary habits and perception of vegetable intake of elementary students in Gwangju and Jeonnam Gokseong county. Data collection was conducted from 5th and 6th grade students of elementary schools in Gwangju and Jeonnam Gokseong county using a structured questionnaire survey. The SPSS program was used for statistics processing and data analysis. The chi-square test was also conducted. In terms of dietary intake habits, female students consumed their meals slower than male students. Information on dietary habits and nutrition was commonly obtained from family, including the mother or father who commonly prepared meals at home. Snacks were commonly consumed less than twice daily, with the Gwangju area having a higher frequency of snacks than the Jeonnam area. Elementary students indicated that vegetables were their least favorite food, with female students having a higher interest in vegetables than male students. The pattern and perception of vegetable intake came when the students (that did not eat vegetables) were lectured by their parents on the nutritive value of vegetables. Most students understood the important nutritional ingredients of vegetables. In the case of an interest in vegetables, the Gwangju area showed significantly more comprehension than the Jeonnam area on the definition and role of dietary fiber, the dental benefits of dietary fiber, and the identification of the environment-friendly certification mark.

The role of dietary fiber in regulating lipid bioaccessibility of almonds during mastication

Almonds contain phytochemicals and nutrients that potentially have positive health benefits in relation to heart disease, diabetes and obesity. One important mechanism associated with these benefits is the bioaccessibility (release) of lipids from the almond tissue during mastication and digestion. Indeed, it has been reported that in human subjects on almond‐rich diets, a significant proportion of lipid remains undigested, mainly caused by the entrapment of lipid by intact cell walls (dietary fiber). However, the bioaccessibility of almond lipid has not yet been quantified. We have studied this by performing a mastication trial in healthy human volunteers (n = 15). The particle size distribution of chewed almonds was measured using mechanical sieving and laser diffraction methods. Lipid release from ruptured almond cells was estimated using a theoretical model based on the particle size of the chewed almond tissue and the diameter of the lipid‐rich cells. Our results showed that laser diffraction was the most reliable and efficient method. Lipid release from masticated almonds was estimated to be ~30% of total lipid and originated from the ruptured cells of the fractured tissue. This indicates that the majority of almond lipid is unavailable for the early stages of digestion. Further work will extend to studies of lipid release and digestion at more distal sites of the gastrointestinal tract. This work was funded by the BBSRC, UK (DRINC; BB/H004866/1).

Comparison of some functional properties and chemical constituents of dietary fibers of Iranian rice bran extracted by chemical and enzymatic methods

Rice is the second most consumed cereal grain in the world. It consists of almost 20% rice bran which is a by-product during the milling process in the production of white rice from brown rice. Bran is often used for non-food applications including animal feed stock, fuel, fertilizer or for preventing clumping; as this by-product is enriched with nutrients and dietary fibre, it is also used in food industries. Since the middle of the 1970s when the role of dietary fibre was known in health, it has caught public attention. This study reveals some compositional and functional analysis of dietary fibre extracted from rice bran using chemical and enzymatic methods. The results show that dietary fibre extracted from rice bran using enzymatic method is the best dietary fibre for food applications. Key words : Rice bran, dietary fiber, chemical extraction, enzymatic extraction.

Beta Glucan: Health Benefits in Obesity and Metabolic Syndrome

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

Intake of dietary fiber, especially from cereal foods, is associated with lower incidence of colon cancer in the HELGA cohort

The role of dietary fiber on the risk of colon and rectal cancer has been investigated in numerous studies, but findings have been inconsistent. The purpose of this study was to examine associations between intake of dietary fiber and risk of incident colon (including distal and proximal colon) and rectal cancer in the prospective Scandinavian HELGA cohort and to determine if fiber source (vegetables, fruits, potatoes, cereals) impacted the association. We included 1,168 incident cases (691 colon, 477 rectal cancer), diagnosed during a median of 11.3 years, among 108,081 cohort members. Sex-specific incidence rate ratios (IRRs) of colon and rectal cancer were related to intake of total or specific fiber source using Cox proportional hazards models. For men, an inverse association was observed between intake of total fiber and the risk of colon cancer per an incremental increase of 10 g day(-1) , IRR (95% CI): 0.74 (0.64-0.86). Intake of cereal fiber per 2 g day(-1) was associated with an IRR of 0.94 (0.91-0.98), which was also seen for intake of cereal fiber from foods with high fiber content (≥ 5 g per 100 g product), where the IRR per 2 g day(-1) was 0.94 (0.90-0.98). In women, intake of cereal fiber per 2 g day(-1) was also associated with lower risk of colon cancer, 0.97 (0.93-1.00). No clear associations were seen for rectal cancer. Our data indicate a protective role of total and cereal fiber intake, particularly from cereal foods with high fiber content, in the prevention of colon cancer.

Influence of substrate oxidation on the reward system, no role of dietary fibre

It has been suggested that a high intake of dietary fibre helps regulate energy intake and satiety. The present study aimed to examine whether dietary fibre influenced the liking and wanting components of the food reward system, the metabolic state or subsequent intake. Five sessions involving 32 normal-weight subjects (16 men and 16 women, 30.6 ± 7.6 year) were held. The sessions differed in the composition of the bread eaten during breakfasts (dietary fibre content varied from 2.4 to 12.8 g/100 g). Several factors such as the palatability, weight, volume, energy content and macronutrient composition of the breakfasts were adjusted. Energy expenditure, the respiratory quotient (R), olfactory liking for four foods, wanting for six other foods, and hunger sensations were evaluated before and after the breakfast, as well as before a morning snack. The results showed no significant differences after ingestion of the various breads. Interestingly, R correlated with olfactory liking and with wanting, which highlights in an original manner the influence of the metabolic state on hedonic sensations for food. In conclusion, dietary fibre was found to have no effect on olfactory liking and wanting, and had no detectable effect on satiety sensations or on subsequent energy intake.

Dietary fibres in the regulation of appetite and food intake. Importance of viscosity

Dietary fibres have many functions in the diet, one of which may be to promote control of energy intake and reduce the risk of developing obesity. This is linked to the unique physico-chemical properties of dietary fibres which aid early signalling of satiation and prolonged or enhanced sensation of satiety. Particularly the ability of some dietary fibres to increase viscosity of intestinal contents offers numerous opportunities to affect appetite regulation. Few papers on the satiating effect of dietary fibres include information on the physico-chemical characteristics of the dietary fibres being tested, including molecular weight and viscosity. For viscosity to serve as a proxy for soluble dietary fibres it is essential to have an understanding of individual dietary fibre viscosity characteristics. The goal of this paper is to provide a brief overview on the role of dietary fibres in appetite regulation highlighting the importance of viscosity.

TOWARDS REDUCED FEEDING COSTS, DIETARY SAFETY AND MINIMAL MINERAL EXCRETION IN RABBITS : A REVIEW

This article reviews some actual trends in rabbit nutrition. To be more competitive with poultry and pig production, a further reduction of the overall feed conversion rate of rabbitries till 3.25 is necessary. Genetic, management and nutritional improvements are simultaneously possible to achieve this goal and are discussed in this paper. A trend towards phase feeding is observed in rabbit nutrition. Several arguments are given: (i) requirements of fatteners are different shortly after weaning compared to the finishing period; (ii) by matching the dietary protein (amino acids) to the age related requirements, diets with a lower protein level can be fed, resulting in a significant reduced N-excretion. This is of special importance to reduce the environmental pollution, in areas with a high density of animal production. Finally, (iii) energy concentrated diets can be fed in the finishing period to improve the feed conversion rate. A policy till a further banning of feed additives can be expected. Disease control, including dietary safety will be of increasing interest. The role of dietary fibre and starch on rabbit health has recently been better defined. Lignin has a predominant role on the transit time and to reduce the incidence of enterits. A lignin (ADL>5%), starch (<13.5%) and cellulose constrain (>15%) is suggested in diet formulation for young rabbits instead of a single recommendation for crude fibre or ADF. However, dietary fibre and starch recommendations are depending from age and physiological status.

Dietary fiber, source foods and colorectal cancer risk: the Fukuoka Colorectal Cancer Study

Objective. Despite much evidence from laboratory work, epidemiological evidence remains elusive regarding the role of dietary fiber in colorectal carcinogenesis. We investigated associations of dietary fiber and source foods with colorectal cancer risk in the Fukuoka Colorectal Cancer Study, a community-based case–control study. Material and methods. The study subjects were 816 incident cases of colorectal cancer and 815 community controls. Nutrient and food intakes were estimated on the basis of a computer-assisted interview regarding 148 dietary items. Odds ratios of colorectal cancer according to quintile categories of energy-adjusted intakes of dietary fiber and food groups were obtained with adjustment for non-dietary factors and dietary intakes of calcium and n−3 fatty acids. Results. Total, soluble and insoluble dietary fibers were not measurably associated with overall risk or subsite-specific risk of colorectal cancer. By contrast, rice consumption was associated with a decreased risk of colorectal cancer (trend p = 0.03), particularly of distal colon and rectal cancer (trend p = 0.02), and high intake of non-rice cereals tended to be related to an increased risk of colon cancer (trend p = 0.07). There was no association between vegetable consumption and colorectal cancer, whereas individuals with the lowest intake of fruits tended to have an increased risk of colorectal cancer. Conclusions. The present study did not corroborate a protective association between dietary fiber and colorectal cancer, but suggested a decreased risk of distal colorectal cancer associated with rice consumption.

Role of Dietary Fiber in Formation and Prevention of Small Intestinal Ulcers Induced by Nonsteroidal Anti-Inflammatory Drug

Recent advances in endoscopic techniques such as capsule endoscopy have revealed that nonsteroidal anti-inflammatory drugs (NSAIDs) often cause ulcers in the small intestine in humans, but there are few effective agents for treatment of small intestinal ulcers. Although the pathogenesis of NSAID-induced intestinal ulcer has been widely studied, dietary factors have seldom been considered. In the present review, the role of dietary fiber (DF) in the formation of NSAID-induced intestinal ulcers is discussed. In previous studies, small intestinal lesions were not observed when NSAIDs were administered to fasted rats, dogs, and cats, but were observed in conventionally-fed animals, suggesting the importance of feeding in the formation of intestinal lesions induced by NSAIDs. However, in animals fed diets containing low or no DF, indomethacin (IND) did not produce lesions in the small intestine, but did produce lesions in animals fed diets supplemented with insoluble dietary fiber (IDF, cellulose). The results suggest that IDF in the diet plays an important role in the formation of NSAID-induced intestinal lesions. On the other hand, addition of soluble dietary fibers (SDFs) such as pectin or mucin to regular diet markedly decreased NSAID-induced intestinal lesions. Thus, IDF and SDF have opposing effects on IND-induced intestinal lesions, i.e., IDF is harmful while SDF is protective. SDFs potentially represent a novel and safe means for protecting the small intestine against NSAID-induced intestinal lesions.

Preventing Cardiovascular Disease in Older Adults: The Role of Fiber

The role of dietary fiber in the prevention of cardiovascular disease has received increasing attention as supportive data have accumulated. Recent studies have found a consistently protective effect of diets that are high in fiber on cardiovascular disease outcomes, prompting many leading organizations to recommend increased fiber in the daily diet. However, the biologic mechanisms underlying how fiber influences the cardiovascular system have yet to be fully elucidated. Epidemiologic evidence demonstrating that high fiber diets (&gt;20–30 g/day) are beneficial, coupled with new evidence of a possible metabolic effect on inflammatory markers, insulin resistance and lipids, suggest that there may be several important mediators in the association between dietary fiber and cardiovascular disease. Further research is needed regarding the optimal intake amount of fiber and which sources of fiber are most beneficial in the prevention of cardiovascular disease in older adults.

Dietary fiber and colorectal cancer: what is appropriate advice?

Two recent studies question the role of dietary fiber in the prevention of colorectal cancer. However, the duration of dietary intervention, dose of fiber, and the complexity of polyp formation and transformation to carcinomas make interpretation of such studies difficult. Multiple rationales exist for promoting the consumption of high-fiber, low-fat, fruit- and vegetable-rich diets.