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Purpose of review To describe the evidences for the usefulness of dietary manipulations (including the use of probiotics and prebiotics) in the management of irritable bowel syndrome (IBS). Recent findings Exclusion diets do not have a role in the management of these patients except in the case of malabsorbed sugars (lactose, fructose). However, recent work suggests that excluding these sugars is more effective in non-IBS than in IBS patients. Also, the first small open series on the use of very low (20 g/day) carbohydrate diet (VLCD) in IBS has been published with promising results. However, safety concerns do not allow us to recommend them. In the period of review, further evidence has been provided on the role of psyllium in IBS. Also, the available evidence on the use of probiotics in IBS has been meta-analyzed. Summary IBS patients should eat a balanced diet without restrictions, and (except for malabsorbed sugars) exclusion diets are not useful in most of them. The role of VLCD remains to be established. The concept that increasing fiber intake is useful for IBS may not be true for all patients, and hydrophilic colloids (e.g. psyllium) are preferred. There is growing evidence for the effectiveness of probiotics in IBS.

Nutritional derangements are frequent in inflammatory bowel disease. In the past year significant work has been published examining the mechanisms of impaired food intake in animal models of inflammatory bowel disease, which allow a better understanding of these processes. Data from the same laboratory have shed further light on the relative role of underfeeding and inflammation on the growth retardation associated with intestinal inflammation. Other studies have provided further data on the risk factors and predictive biomarkers of bone loss in patients with inflammatory bowel disease. The potential role of enteral nutrition as primary therapy for Crohn's disease is particularly addressed in this review. Recent contributions to the field emphasized the special importance of this modality of therapy in paediatric patients. The possible mechanisms for such a therapeutic action are not well understood. Other nutrients may have a therapeutic potential in inflammatory bowel disease. In particular, recent data on the in-vivo anti-inflammatory actions of butyrate merit special mention. Finally, novel nutritional therapeutic strategies for inflammatory bowel disease, such as transforming growth factor-beta2-enriched enteral feeding, or hydrothermally processed cereals have recently been explored.

In the last year some relevant papers on nutrition and metabolism in chronic liver disease and transplantation have been published. Studies investigating the reliability of predicting energy expenditure in cirrhosis, and some relevant contributions to the understanding of metabolic consequences of liver transplantation, deserve particular mention. These include the first direct evidence that liver transplantation corrects the insulin resistance present in cirrhosis, as well as studies on the role of genetic polymorphism of the vitamin D receptor gene in bone loss after transplantation. Other papers have dealt with body composition, polyunsaturated fatty acid and antioxidant status in cirrhosis. However, relevant contributions in the field of nutritional support in cirrhosis are surprisingly lacking.

Significant contributions to the field of nutrition and liver disease have been published in the last year. The most relevant includes work on the pathogenic role of energy metabolism disturbances in the development of malnutrition in cirrhosis, as well as data on the relationship between preoperative nutritional deficiencies and the outcome of liver transplantation. However, despite these contributions, large-scale multicentric trials on the therapeutic value of nutritional support and metabolic care in cirrhosis and liver transplantation are still lacking.

Purpose of review To describe the evidences for and against the different nutritional and nonnutritional therapeutic approaches for severe alcoholic steatohepatitis, based on data from randomized controlled trials, in order to answer the question posed in the title: 'more of the same or something new?'. Recent findings Very few papers assessing old or new therapeutic strategies for severe alcoholic steatohepatitis have been published in the last 18 months. In addition, all of them provide negative results. A meta-analysis of the trials using anabolic steroids in alcoholic steatohepatitis confirmed the lack of benefit associated with this therapy. Also, two randomized controlled trials failed to disclose any positive effect of different antioxidant mixture in these patients. Summary The answer to the question posed in the title of this review must unfortunately be 'nothing new, but just the same!'.

The aim of this paper is to describe the relevant medical literature published between spring 2003 and spring 2005 in the field of malnutrition in liver disease and its management.The most relevant articles covered in this paper provide data regarding the absence of energy imbalance in patients with stable cirrhosis, thus arguing against its potential role in the development of malnutrition; the increase in body cell mass and muscle mass as the major components of weight gain after portal-systemic shunting; the largest published randomized controlled trial of the positive effect of branched-chain amino acid supplements on the long-term outcome of patients with cirrhosis; studies using stable isotope labeled substrates, suggesting that dietary fat could be absorbed via the portal vein in patients with cirrhosis; and a randomized controlled trial suggesting the possibility that probiotics may decrease the infection rate after liver transplantation.In spite of the data provided by these and other articles described in the review, the major controversial issues in the field of nutritional management of liver disease remain open. Particularly remarkable is the lack of consensus regarding the nutritional management of acute liver failure.

This article describes the clinical papers published in 2002 and early 2003 on nutritional and metabolic derangement in inflammatory bowel disease.Insulin-like growth factor 1 and Insulin-like growth factor binding protein 3 are decreased in inflammatory bowel disease, and disease therapy hardly reverses this situation. There are promising data on recombinant human growth hormone therapy in paediatric inflammatory bowel disease. Several papers have added some fuel to the debate on the prevalence and pathogenesis of metabolic bone disease in inflammatory bowel disease. Articles have been published investigating the role of dietary fat in the therapeutic action of enteral feeding in Crohn's disease. Low-fat diets are particularly useful, and adding medium-chain triglycerides does not impair the effectiveness of these diets. Balanced amounts of saturated, monounsaturated and polyunsaturated fat should probably be used. Relevant contributions on the usefulness of probiotic preparations (VSL#3) in the treatment and prevention of pouchitis have been published. Other papers deal with the effects of medical and surgical therapy on body composition and metabolism in the inflammatory bowel disease, the treatment of oxidative stress of these patients, and the possible role of some vitamin deficiencies on thrombotic risk in the condition.Inflammatory bowel disease therapy hardly reverses growth hormone-insulin-like growth factor 1 disturbances of patients. The role of inflammation and steroid therapy of metabolic bone disease in inflammatory bowel disease is still controversial. Low-fat diets, with added amounts of medium-chain triglycerides, are useful in decreasing gut inflammation in the condition. The search for the optimal dietary fatty acid composition deserves further investigations. The use of probiotics and prebiotics opens new therapeutic perspectives for the disease.

In the past year, some relevant papers related to the diagnosis of malnutrition and its pathogenesis in cirrhosis have been published. The value of anthropometrics in the nutritional assessment of end-stage cirrhotic patients has been reinforced. Also, the role of bioelectrical impedance analysis in these patients has been redefined. Several papers have investigated the relationship between leptin and malnutrition in chronic liver disease, particularly the role of alcoholism in hyperleptinaemia, and the importance of protein-bound leptin in these patients. In other papers, the impact of both undernutrition and obesity on the outcome of liver transplantation has been investigated. Two randomized, controlled trials on enteral nutrition in liver disease have been published in this period. One of them deals with a clinical situation (i.e. severe alcoholic hepatitis) associated with a high mortality rate, whereas the second is the first controlled trial in the field of preoperative nutrition in liver transplantation. Finally, some papers provide further arguments in the dilemma of which route of nutrition (enteral or parenteral) is better in cirrhosis.

In the past year, some relevant papers on the mechanisms of malnutrition in cirrhosis have been published. Studies investigating the metabolic destiny of leucine after protein breakdown, which have contributed to a better understanding of the pathogenesis of muscle wasting and fat depletion in these patients, deserve particular mention. Also, the demonstration that chronically reducing hyperinsulinaemia in cirrhosis is able to improve insulin sensitivity opens novel pathogenic and therapeutic perspectives for such a metabolic derangement in these patients. Other papers dealt with unsaturated lipids, lipoperoxidation and antioxidants in chronic liver disease. However, randomized trials on parenteral or enteral nutrition in cirrhosis and liver transplantation are missing.