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The Management Committee of COST 92 appointed delegates for different European countries to collect data of fiber intakes, data from food balance sheets and individual fiber intakes. The data received exhibit that 50% of dietary fiber is obtained from cereals, 31% from vegetables, 16% from fruit and 3% from other sources. These data suggest the researchers to make a detailed study of European foods for fiber and formation of European-wide food tables.

Coeliac disease is a lifelong intolerance to the gluten found in wheat, barley and rye, and some patients are also sensitive to oats. The disease is genetically determined, with 10% of the first-degree relatives affected and 75% of monozygotic twins being concordant. Of the patients with coeliac disease 95% are human leucocyte antigen (HLA)-DQ2 or HLA-DQ8 positive. Characteristically, the jejunal mucosa becomes damaged by a T-cell-mediated autoimmune response that is thought to be initiated by a 33-mer peptide fragment in A2 gliadin, and patients with this disorder have raised levels of anti-endomysium and tissue transglutaminase antibodies in their blood. Coeliac disease is the major diagnosable food intolerance and, with the advent of a simple blood test for case finding, prevalence rates are thought to be approximately 1:100. Classically, the condition presented with malabsorption and failure to thrive in infancy, but this picture has now been overtaken by the much more common presentation in adults, usually with non-specific symptoms such as tiredness and anaemia, disturbance in bowel habit or following low-impact bone fractures. Small intestinal biopsy is necessary for diagnosis and shows a characteristically flat appearance with crypt hypoplasia and infiltration of the epithelium with lymphocytes. Diet is the key to management and a gluten-free diet effectively cures the condition. However, this commitment is lifelong and many aisles in the supermarket are effectively closed to individuals with coeliac disease. Compliance can be monitored by measuring antibodies in blood, which revert to negative after 6-9 months. Patients with minor symptoms, who are found incidentally to have coeliac disease, often ask whether it is necessary to adhere to the diet. Current advice is that dietary adherence is necessary to avoid the long-term complications, which are, principally, osteoporosis and small bowel lymphoma. However, risk of these complications diminishes very considerably in patients who are on a gluten-free diet. [ABSTRACT FROM AUTHOR]

Diet plays an important role in the primary and secondary prevention of cardiovascular disease. The growing perception that abnormal haemostatic processes of coagulation, platelet aggregation and fibrinolysis contribute to cardiovascular disease aetiology motivated this review on the relationships of diet, specific foods and nutrients with haemostatic function. Functional endpoints that reflect the function and status of some of these processes and which can be measured in dietary trials are identified. The effects of energy intake and expenditure, alcohol, total fat and specific fatty acids, non-starch polysaccharides (dietary fibre), antioxidant nutrients and some foods on a variety of haemostatic markers are reviewed. The results indicate that the prudent low-fat, high-fibre diet and maintenance of ideal body weight recommended to protect against and treat hyperlipidaemia and coronary heart disease will also benefit haemostatic profiles. It is concluded that more research on specific effects is needed for improved recommendations on a population level for prevention of cardiovascular disease. [ABSTRACT FROM AUTHOR]

BACKGROUND: The gut and immune system form a complex integrated structure that has evolved to provide effective digestion and defence against ingested toxins and pathogenic bacteria. However, great variation exists in what is considered normal healthy gut and immune function. Thus, whilst it is possible to measure many aspects of digestion and immunity, it is more difficult to interpret the benefits to individuals of variation within what is considered to be a normal range. Nevertheless, it is important to set standards for optimal function for use both by the consumer, industry and those concerned with the public health. The digestive tract is most frequently the object of functional and health claims and a large market already exists for gut-functional foods worldwide. AIM: To define normal function of the gut and immune system and describe available methods of measuring it. RESULTS: We have defined normal bowel habit and transit time, identified their role as risk factors for disease and how they may be measured. Similarly, we have tried to define what is a healthy gut flora in terms of the dominant genera and their metabolism and listed the many, varied and novel methods for determining these parameters. It has proved less easy to provide boundaries for what constitutes optimal or improved gastric emptying, gut motility, nutrient and water absorption and the function of organs such as the liver, gallbladder and pancreas. The many tests of these functions are described. We have discussed gastrointestinal well being. Sensations arising from the gut can be both pleasant and unpleasant. However, the characteristics of well being are ill defined and merge imperceptibly from acceptable to unacceptable, a state that is subjective. Nevertheless, we feel this is an important area for future work and method development. The immune system is even more difficult to make quantitative judgements about. When it is defective, then clinical problems ensure, but this is an uncommon state. The innate and adaptive immune systems work synergistically together and comprise many cellular and humoral factors. The adaptive system is extremely sophisticated and between the two arms of immunity there is great redundancy, which provides robust defences. New aspects of immune function are discovered regularly. It is not clear whether immune function can be 'improved'. Measuring aspects of immune function is possible but there is no one test that will define either the status or functional capacity of the immune system. Human studies are often limited by the ability to sample only blood or secretions such as saliva but it should be remembered that only 2% of lymphocytes circulate at any given time, which limits interpretation of data.We recommend assessing the functional capacity of the immune system by: measuring specific cell functions ex vivo. measuring in vivo responses to challenge, e. g. change in antibody in blood or response to antigens. determining the incidence and severity of infection in target populations during naturally occurring episodes or in response to attenuated pathogens. [ABSTRACT FROM AUTHOR]

For more than 200 years the fibre in plant foods has been known by animal nutritionists to have significant effects on digestion. Its role in human nutrition began to be investigated towards the end of the 19th century. However, between 1966 and 1972, Denis Burkitt, a surgeon who had recently returned from Africa, brought together ideas from a range of disciplines together with observations from his own experience to propose a radical view of the role of fibre in human health. Burkitt came late to the fibre story but built on the work of three physicians (Peter Cleave, G. D. Campbell and Hugh Trowell), a surgeon (Neil Painter) and a biochemist (Alec Walker) to propose that diets low in fibre increase the risk of CHD, obesity, diabetes, dental caries, various vascular disorders and large bowel conditions such as cancer, appendicitis and diverticulosis. Simply grouping these diseases together as having a common cause was groundbreaking. Proposing fibre as the key stimulated much research but also controversy. Credit for the dietary fibre hypothesis is given largely to Burkitt who became known as the 'Fibre Man'. This paper sets out the story of the development of the fibre hypothesis, and the contribution to it of these individuals.

Bacteria belonging to the normal colonic microbiota are associated with the etiology of ulcerative colitis (UC). Although several mucosal species have been implicated in the disease process, the organisms and mechanisms involved are unknown. The aim of this investigation was to characterize mucosal biofilm communities over time and to determine the relationship of these bacteria to patient age and disease severity and duration. Multiple rectal biopsy specimens were taken from 33 patients with active UC over a period of 1 year. Real-time PCR was used to quantify mucosal bacteria in UC patients compared to 18 noninflammatory bowel disease controls, and the relationship between indicators of disease severity and bacterial colonization was evaluated by linear regression analysis. Significant differences were detected in bacterial populations on the UC mucosa and in the control group, which varied over the study period. High clinical activity indices (CAI) and sigmoidoscopy scores (SS) were associated with enterobacteria, desulfovibrios, type E Clostridium perfringens, and Enterococcus faecalis, whereas the reverse was true for Clostridium butyricum, Ruminococcus albus, and Eubacterium rectale. Lactobacillus and bifidobacterium numbers were linked with low CAI. Only E. rectale and Clostridium clostridioforme had a high age dependence. These findings demonstrated that longitudinal variations in mucosal bacterial populations occur in UC and that bacterial community structure is related to disease severity.

Background: Crohn's disease is an inflammatory illness in which the immune response against gut microorganisms is believed to drive an abnormal immune response. Consequently, modification of mucosal bacterial communities, and the immune effects they elicit, might be used to modify the disease state., Aim: To investigate the effects of synbiotic consumption on disease processes in patients with Crohn's disease., Methods: A randomized, double-blind placebo-controlled trial was conducted involving 35 patients with active Crohn's disease, using a synbiotic comprising Bifidobacterium longum and Synergy 1. Clinical status was scored and rectal biopsies were collected at the start, and at 3- and 6-month intervals. Transcription levels of immune markers and mucosal bacterial 16S rRNA gene copy numbers were quantified using real-time PCR., Results: Significant improvements in clinical outcomes occurred with synbiotic consumption, with reductions in both Crohn's disease activity indices (P = 0.020) and histological scores (P = 0.018). The synbiotic had little effect on mucosal IL-18, INF-gamma and IL-1beta; however, significant reductions occurred in TNF-alpha expression in synbiotic patients at 3 months (P = 0.041), although not at 6 months. Mucosal bifidobacteria proliferated in synbiotic patients., Conclusion: Synbiotic consumption was effective in improving clinical symptoms in patients with active Crohn's disease., (2010 Blackwell Publishing Ltd.)

There is impressive evidence from epidemiological and experimental studies that dietary fibre derived form vegetables, fruit and wholegrain cereals protects against and may be useful in the treatment of a wide range of diseases. However, while there is some evidence of benefit of extracted and synthetic fibres in terms of lowering levels of cardiovascular risk factors, improving measures of glycaemic control and gastrointestinal function, epidemiological confirmation of clinical benefit and long term safety are lacking. An appropriate definition of dietary fibre is essential, given that claiming a food is high in dietary fibre is in effect making a health claim, without formally doing so. The new Codex definition acknowledges the difference between naturally occurring carbohydrate polymers which are neither digested nor absorbed in the human small intestine and synthetic or extracted polymers. However the latter two groups may also be defined as dietary fibre provided "beneficial physiological effect has been demonstrated by generally accepted scientific evidence". Given the need for a definition of dietary fibre which can be used for food labelling, setting nutrient reference values and decisions relating to health claims it is important to achieve agreement as to what constitutes a meaningful physiological effect and the level of evidence required to be certain of such effect.

The energy values of carbohydrates continue to be debated. This is because of the use of different energy systems, for example, combustible, digestible, metabolizable, and so on. Furthermore, ingested macronutrients may not be fully available to tissues, and the tissues themselves may not be able fully to oxidize substrates made available to them. Therefore, for certain carbohydrates, the discrepancies between combustible energy (cEI), digestible energy (DE), metabolizable energy (ME) and net metabolizable energy (NME) may be considerable. Three food energy systems are in use in food tables and for food labelling in different world regions based on selective interpretation of the digestive physiology and metabolism of food carbohydrates. This is clearly unsatisfactory and confusing to the consumer. While it has been suggested that an enormous amount of work would have to be undertaken to change the current ME system into an NME system, the additional changes may not be as great as anticipated. In experimental work, carbohydrate is high in the macronutrient hierarchy of satiation. However, studies of eating behaviour indicate that it does not unconditionally depend on the oxidation of one nutrient, and argue against the operation of a simple carbohydrate oxidation or storage model of feeding behaviour to the exclusion of other macronutrients. The site, rate and extent of carbohydrate digestion in, and absorption from the gut are key to understanding the many roles of carbohydrate, although the concept of digestibility has different meanings. Within the nutrition community, the characteristic patterns of digestion that occur in the small (upper) vs large (lower) bowel are known to impact in contrasting ways on metabolism, while in the discussion of the energy value of foods, digestibility is defined as the proportion of combustible energy that is absorbed over the entire length of the gastrointestinal tract. Carbohydrates that reach the large bowel are fermented to short-chain fatty acids. The exact amounts and types of carbohydrate that reach the caecum are unknown, but are probably between 20 and 40 g/day in countries with 'westernized' diets, whereas they may reach 50 g/day where traditional staples are largely cereal or diets are high in fruit and vegetables. Non-starch polysaccharides clearly affect bowel habit and so, to a lesser extent, does resistant starch. However, the short-chain carbohydrates, which are also found in breast milk, have little if any laxative role, although do effect the balance of the flora. This latter property has led to the term 'prebiotic', which is defined as the capacity to increase selectively the numbers of bifidobacteria and lactobacilli without growth of other genera. This now well-established physiological property has not so far led through to clear health benefits, but current studies are focused on their potential to prevent diarrhoeal illnesses, improve well-being and immunomodulation, particularly in atopic children and on increased calcium absorption.

Dietary carbohydrates are a group of chemically defined substances with a range of physical and physiological properties and health benefits. As with other macronutrients, the primary classification of dietary carbohydrate is based on chemistry, that is character of individual monomers, degree of polymerization (DP) and type of linkage (alpha or beta), as agreed at the Food and Agriculture Organization/World Health Organization Expert Consultation in 1997. This divides carbohydrates into three main groups, sugars (DP 1-2), oligosaccharides (short-chain carbohydrates) (DP 3-9) and polysaccharides (DP> or =10). Within this classification, a number of terms are used such as mono- and disaccharides, polyols, oligosaccharides, starch, modified starch, non-starch polysaccharides, total carbohydrate, sugars, etc. While effects of carbohydrates are ultimately related to their primary chemistry, they are modified by their physical properties. These include water solubility, hydration, gel formation, crystalline state, association with other molecules such as protein, lipid and divalent cations and aggregation into complex structures in cell walls and other specialized plant tissues. A classification based on chemistry is essential for a system of measurement, predication of properties and estimation of intakes, but does not allow a simple translation into nutritional effects since each class of carbohydrate has overlapping physiological properties and effects on health. This dichotomy has led to the use of a number of terms to describe carbohydrate in foods, for example intrinsic and extrinsic sugars, prebiotic, resistant starch, dietary fibre, available and unavailable carbohydrate, complex carbohydrate, glycaemic and whole grain. This paper reviews these terms and suggests that some are more useful than others. A clearer understanding of what is meant by any particular word used to describe carbohydrate is essential to progress in translating the growing knowledge of the physiological properties of carbohydrate into public health messages.

Background: Prebiotics are short-chain carbohydrates that alter the composition, or metabolism, of the gut microbiota in a beneficial manner. It is therefore expected that prebiotics will improve health in a way similar to probiotics, whilst at the same time being cheaper, and carrying less risk and being easier to incorporate into the diet than probiotics., Aim: To review published evidence for prebiotic effects on gut function and human health., Methods: We searched the Science Citation Index with the terms prebiotic, microbiota, gut bacteria, large intestine, mucosa, bowel habit, constipation, diarrhoea, inflammatory bowel disease, Crohn's disease, ulcerative colitis, pouchitis, calcium and cancer, focussing principally on studies in humans and reports in the English language. Search of the Cochrane Library did not identify any clinical study or meta-analysis on this topic., Results: Three prebiotics, oligofructose, galacto-oligosaccharides and lactulose, clearly alter the balance of the large bowel microbiota by increasing bifidobacteria and Lactobacillus numbers. These carbohydrates are fermented and give rise to short-chain fatty acid and intestinal gas; however, effects on bowel habit are relatively small. Randomized-controlled trials of their effect in a clinical context are few, although animal studies show anti-inflammatory effects in inflammatory bowel disease, while calcium absorption is increased., Conclusions: It is still early days for prebiotics, but they offer the potential to modify the gut microbial balance in such a way as to bring direct health benefits cheaply and safely.

Ulcerative colitis (UC) is an acute and chronic inflammatory bowel disease of unknown aetiology, although bacterial species belonging to the normal colonic microbiota are known to be involved in its initiation and maintenance. Several organisms have been linked to the disease; however, mucosa-associated bacteria are more likely to be involved than their luminal counterparts, due to their close proximity to the host epithelium. Comparative bacteriological analyses were done on rectal biopsies to investigate differences in mucosal bacteria in patients with UC and healthy controls. Complex bacterial communities were found in both groups, with significant reductions in bifidobacterial numbers in UC, which suggested that they might have a protective role in the disease. Accordingly, a therapy for treating UC was designed, with the aim of modifying the mucosal microbiota to increase bifidobacterial colonisation and reduce inflammation. Ranges of mucosal and faecal bifidobacteria were tested for their substrate preferences and their abilities to survive under a variety of environmental conditions. A synbiotic comprising a probiotic (Bifidobacterium longum) isolated from healthy rectal mucosa combined with a prebiotic (oligofructose-enriched inulin - Synergy 1) was developed. The treatment was used in a randomised controlled trial involving eighteen patients with active UC, for a period of 1 month. Rectal biopsies were collected at the beginning and end of the study. Bacteriological analysis and transcription levels of epithelium-related immune markers were assessed. Results demonstrated that short-term synbiotic treatment resulted in increased bifidobacterial colonisation of the rectal mucosa and induced significant reductions in the expression of molecules that control inflammation in active UC.

Background: The relapsing nature and varying geographical prevalence of ulcerative colitis (UC) implicates environmental factors such as diet in its aetiology., Methods: In order to determine which foods might be related to disease activity in UC a new method of dietary analysis was developed and applied. Eighty-one UC patients were recruited at all stages of the disease process. Following completion of a 7 d diet diary, clinical assessment including a sigmoidoscopic examination (scale 0 (normal mucosa) to 6 (very active disease)) was conducted. Food weights for each person were adjusted (divided) by the person's calorific intake for the week. Each food consumed was given a food sigmoidoscopy score (FSS) calculated by summing the products of the (adjusted) weight of food consumed and sigmoidoscopy score for each patient and occurrence of food and dividing by the total (adjusted) weight of the food consumed by all 81 patients. Thus, foods eaten in large quantities by patients with very active disease have high FSSs and vice versa. Foods consumed by <10 people or weighing <1 kg for the whole group were excluded, leaving 75 foods., Results: High FSS foods were characterized by high levels of the anti-thiamin additive sulfite (Mann-Whitney, p < 0.001), i.e. bitter, white wine, burgers, soft drinks from concentrates, sausages, lager and red wine. Caffeine also has anti-thiamin properties and decaffeinated coffee was associated with a better clinical state than the caffeine containing version. Beneficial foods (average intake per week) included pork (210 g), breakfast cereals (200 g), lettuce (110 g), apples and pears (390 g), milk (1250 ml), melon (350 g), bananas (350 g), bacon (120 g), beef and beef products (500 g), tomatoes (240 g), soup (700 g), citrus fruits (300 g), fish (290 g), yogurt (410 g), cheese (110 g), potatoes (710 g) and legumes (120 g)., Conclusions: The dietary analysis method described provides a new tool for establishing relationships between diet and disease and indicates a potentially therapeutic diet for UC.

Background and Aims: Ulcerative colitis (UC) is an acute and chronic inflammatory disease of the large bowel with unknown aetiology. The immune response against normal commensal microorganisms is believed to drive inflammatory processes associated with UC. Therefore, modulation of bacterial communities on the gut mucosa, through the use of probiotics and prebiotics, may be used to modify the disease state., Methods: A synbiotic was developed for use in UC patients combining a probiotic, Bifidobacterium longum, isolated from healthy rectal epithelium, and a prebiotic (Synergy 1), a preferential inulin-oligofructose growth substrate for the probiotic strain. Treatment was employed in a double blinded randomised controlled trial using 18 patients with active UC for a period of one month. Clinical status was scored and rectal biopsies were collected before and after treatment, and transcription levels of epithelium related immune markers were measured., Results: Sigmoidoscopy scores (scale 0-6) were reduced in the test group (start 4.5 (1.4), end 3.1 (2.5)) compared with placebo (start 2.6 (2.1), end 3.2 (2.2)) (p=0.06). mRNA levels for human beta defensins 2, 3, and 4, which are strongly upregulated in active UC, were significantly reduced in the test group after treatment (p=0.016, 0.038, and 0.008, respectively). Tumour necrosis factor alpha and interleukin 1alpha, which are inflammatory cytokines that drive inflammation and induce defensin expression, were also significantly reduced after treatment (p=0.018 and 0.023, respectively). Biopsies in the test group had reduced inflammation and regeneration of epithelial tissue., Conclusions: Short term synbiotic treatment of active UC resulted in improvement of the full clinical appearance of chronic inflammation in patients receiving this therapy.

Background and Aims: The mucosa associated flora of the large intestine is important in determining mucosal function although what controls its composition is unknown. This study has determined the effect of the prebiotic carbohydrates oligofructose and inulin on the mucosal flora., Methods: An in vitro chemostat model of both planktonic and surface associated bacteria was used followed by an intervention study in 29 subjects undergoing colonoscopy., Subjects: Fourteen subjects, recruited from colonoscopy waiting lists, supplemented their diet for two weeks with a mix of 7.5 g of oligofructose and 7.5 g inulin. Fifteen subjects were recruited at the time of colonoscopy and given no supplement. Multiple endoscopic biopsies were taken from the caecum, transverse and descending colon, and rectum. The mucosal flora was characterised by culture and to species level by cellular fatty acid profiles. Cell proliferation was assessed by immunohistochemical staining for minichromosome maintenance protein 2, Ki67, and proliferating cell nuclear antigen., Results: In vitro prebiotics increased surface counts of bifidobacteria from 6.6 to 7.3 log(10) colony forming units (CFU) per slide (p<0.0006) with no significant changes in planktonic bacteria. In the feeding study, prebiotics increased mucosal bifidobacteria (log CFU/g mucosa (SEM)) in both the proximal (control 5.3 (0.4) v prebiotic 6.3 (0.3)) (p = 0.059) and distal (control 5.2 (0.3) v prebiotic 6.4 (0.3)) colon (p = 0.01). Lactobacilli were also increased (3.0 (0.1) v 3.7 (0.2) (p = 0.02) in the proximal and 3.1 (0.1) v 3.6 (0.2) (p = 0.04) in the distal colon, respectively). There were significantly more eubacteria in fed subjects but no changes in total anaerobes clostridia, bacteroides, or coliforms, nor in proliferation indices., Conclusion: Prebiotic carbohydrates can change the composition of the mucosa associated flora significantly.

Objective: To study the variation in genistein + daidzein intake over a 6-month period and test the reliability of 24 h urinary isoflavones as a biomarker of exposure over time., Design: Dietary genistein + daidzein intake was assessed at various time points throughout six months in 15 healthy subjects. Group 1 (n=8) followed nonsupplemented diets and Group 2 (n=7) took a 35 mg/d isoflavone supplement for 3 months and each subject provided a 24 h urine collection, validated with para-aminobenzoic acid, during weeks 7, 15 and 19. Urine was analysed for genistein and daidzein using LC-MS., Results: Isoflavone intake in Groups 1 and 2 ranged from 0.00 to 1.1 mg/d and 0.1 to 53.1 mg/d, respectively. Urine excretion for both groups ranged from 0.20 to 9.56 mg/d. The relationship between 24 h excretion and isoflavone intake is y=0.44 x +/- 0.03(standard deviation) + 1.57; r=0.89, P<0.001., Conclusion: The 24 h urinary isoflavones can be used as biomarkers of isoflavone exposure over time., (Copyright 2004 Nature Publishing Group)