Early enteral feeding in postsurgical cancer patients. Fish oil structured lipid-based polymeric formula versus a standard polymeric formula

The impact of medium-chain triglycerides on weight loss and metabolic health in individuals with overweight or obesity: A systematic review and meta-analysis

BACKGROUNDS

The efficacy of medium-chain triglycerides (MCTs) for weight management and mitigating metabolic disorders among individuals with overweight and obesity remains a topic of ongoing discussion. Notably, there is a gap in the distinction between pure MCTs and medium-long-chain triglycerides (MLCTs).

METHODS

This meta-analysis investigates the efficacy of MCTs on weight loss and glucolipid metabolism in these populations, explicitly evaluating the differential effects of pure MCTs and MLCTs. We performed a random-effects meta-analysis on relevant studies examining weight loss and glucolipid parameters, incorporating a subgroup analysis conducted based on intervention types, pure MCTs versus MLCTs.

RESULTS

Our findings revealed diets enriched with MCTs are more effective in achieving weight reduction (WMD: -1.53%; 95% CI: -2.44, -0.63; p < 0.01), particularly those containing pure MCTs (WMD: -1.62%; 95% CI: -2.78, -0.46; p < 0.01), compared to long-chain fatty acids (LCTs) enriched diets. However, our subgroup analysis indicates that an MLCTs-enriched diet did not significantly reduce weight loss. Additionally, MCTs-enriched diets were associated with significant reductions in blood triglyceride levels and Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) scores, compared to LCTs-enriched diets.

CONCLUSIONS

Hence, the authors recommend incorporating pure MCTs in dietary interventions for individuals with overweight and obesity, particularly those with comorbidities such as dyslipidemia and impaired glucose metabolism.

Pediatric formulas: Categories, composition, and considerations

Formulas, liquid nutrition, may be consumed orally or via a feeding tube to provide partial or complete nutrition that a given individual could not obtain using natural food stuffs in their native form. A wide range of commercially available formulas exist, which may be used as sole-source nutrition or in conjunction with other foods. Physicians and dietitians must understand the nature of and indications for specific formulas to treat diseases, provide complete nutrition to patients, and avoid harm. Products vary in macronutrient and micronutrient content and calorie concentration among many other factors. They are formulated specifically for patients of specific ages, correlating to nutritional needs and medical diagnoses. Additionally, formula availability, insurance coverage, mode of consumption, physiologic tolerance, and caregiver preference influence formula selection. Caregivers may also make their own pediatric formulas. We review commercial and homemade pediatric formulas.

Immunonutrition vs Standard Nutrition for Cancer Patients: A Systematic Review and Meta-Analysis (Part 1)

The aim of this study was to determine the efficacy of immunonutrition vs standard nutrition in cancer patients treated with surgery. Cochrane Central Register of Controlled Trials, EMBASE, MEDLINE, EBSCOhost, and Web of Science were searched. Sixty-one randomized controlled trials were included. Immunonutrition was associated with a significantly reduced risk of postoperative infectious complications (risk ratio [RR] 0.71 [95% CI, 0.64-0.79]), including a reduced risk of wound infection (RR 0.72 [95% CI, 0.60-0.87]), respiratory tract infection (RR 0.70 [95% CI, 0.59-0.84]), and urinary tract infection (RR 0.69 [95% CI, 0.51-0.94]) as well as a decreased risk of anastomotic leakage (RR 0.70 [95% CI, 0.53-0.91]) and a reduced hospital stay (MD -2.12 days [95% CI -2.72 to -1.52]). No differences were found between the 2 groups with regard to sepsis or all-cause mortality. Subgroup analyses revealed that receiving arginine + nucleotides + ω-3 fatty acids and receiving enteral immunonutrition reduced the rates of wound infection and respiratory tract infection. The application of immunonutrition at 25-30 kcal/kg/d for 5-7 days reduced the rate of respiratory tract infection. Perioperative immunonutrition reduced the rate of wound infection. For malnourished patients, immunonutrition shortened the hospitalization time. Therefore, immunonutrition reduces postoperative infection complications and shortens hospital stays but does not reduce all-cause mortality. Patients who are malnourished before surgery who receive arginine + nucleotides + ω-3 fatty acids (25-30 kcal/kg/d) via the gastrointestinal tract during the perioperative period (5-7 days) may show better clinical efficacy.

Meta-analysis of immunonutrition in major abdominal surgery

Background

The objective of this study was to evaluate the potential benefits of immunonutrition in major abdominal surgery with special regard to subgroups and influence of bias.

Methods

A systematic literature search from January 1985 to July 2015 was performed in MEDLINE, Embase and CENTRAL. Only RCTs investigating immunonutrition in major abdominal surgery were included. Outcomes evaluated were mortality, overall complications, infectious complications and length of hospital stay. The influence of different domains of bias was evaluated in sensitivity analyses. Evidence was rated according to the GRADE Working Group grading of evidence.

Results

A total of 83 RCTs with 7116 patients were included. Mortality was not altered by immunonutrition. Taking all trials into account, immunonutrition reduced overall complications (odds ratio (OR) 0·79, 95 per cent c.i. 0·66 to 0·94; P = 0·01), infectious complications (OR 0·58, 0·51 to 0·66; P &lt; 0·001) and shortened hospital stay (mean difference –1·79 (95 per cent c.i. –2·39 to –1·19) days; P &lt; 0·001) compared with control groups. However, these effects vanished after excluding trials at high and unclear risk of bias. Publication bias seemed to be present for infectious complications (P = 0·002). Non-industry-funded trials reported no positive effects for overall complications (OR 1·13, 0·88 to 1·46; P = 0·34), whereas those funded by industry reported large effects (OR 0·66, 0·48 to 0·91; P = 0·01).

Conclusion

Immunonutrition after major abdominal surgery did not seem to alter mortality (GRADE: high quality of evidence). Immunonutrition reduced overall complications, infectious complications and shortened hospital stay (GRADE: low to moderate). The existence of bias lowers confidence in the evidence (GRADE approach).

Functional foods and their role in cancer prevention and health promotion: a comprehensive review

Following cardiovascular disease, cancer is the second leading cause of death in most affluent countries. The 13.3 million new cases of cancer in 2010 were predicted to cost US$ 290 billion, but the total costs were expected to increases to US$ 458 billion in the year 2030 on basis of World Economic Forum in 2011. More than half of all cancer cases and deaths worldwide are consider being preventable. From its inception, the disease control priorities series has focused attention on delivering efficacious health interventions that can result in dramatic reductions in mortality and disability at relatively modest cost. The approach has been multidisciplinary, and the recommendations have been evidence-based, scalable, and adaptable in multiple settings. Better and more equitable health care is the shared responsibility of governments and international agencies, public and private sectors, and societies and individuals, and all of these partners have been involved in the development of the series. Functional foods are foods and food components that supply health benefits beyond basic nutrition. It's-believed these functional foods do more than simply provide nutrients because they help to maintaining health and thereby reducing the risk of disease. There are some reported evidences showing association between functional foods and cancer. For example, S-ally cysteine of garlic and lycopene from tomatoes in combination form suppressed the development of chemically induced gastric cancer by modulation of apoptosis-associated proteins (reduced Bcl-2/Bax ratio and up-regulation of Bim and caspases 8 and 3) at considerably lower intakes than when these substances were given in isolation. Similarly, vitamin D3 with genistein in combination form precipitated a growth inhibition of prostate cancer cells at much lower concentration than when these substances were provided individually. There are very few studies conducted worldwide to see the effects of functional foods on health or cancer or related states. This review, presents the complex patterns of cancer incidence and death around the world and evidence on effective and cost-effective ways to control cancers. The evaluation of cancer will indicate where cancer treatment is ineffective and wasteful, and offer alternative cancer care packages that are cost-effective and suited to low-resource settings. In the present paper, cancer prevention by functional foods is reviewed and the possible mechanisms of action are described.

Nutritional and Metabolic Derangements in Pancreatic Cancer and Pancreatic Resection

Pancreatic cancer is an aggressive malignancy with a poor prognosis. The disease and its treatment can cause significant nutritional impairments that often adversely impact patient quality of life (QOL). The pancreas has both exocrine and endocrine functions and, in the setting of cancer, both systems may be affected. Pancreatic exocrine insufficiency (PEI) manifests as weight loss and steatorrhea, while endocrine insufficiency may result in diabetes mellitus. Surgical resection, a central component of pancreatic cancer treatment, may induce or exacerbate these dysfunctions. Nutritional and metabolic dysfunctions in patients with pancreatic cancer lack characterization, and few guidelines exist for nutritional support in patients after surgical resection. We reviewed publications from the past two decades (1995–2016) addressing the nutritional and metabolic status of patients with pancreatic cancer, grouping them into status at the time of diagnosis, status at the time of resection, and status of nutritional support throughout the diagnosis and treatment of pancreatic cancer. Here, we summarize the results of these investigations and evaluate the effectiveness of various types of nutritional support in patients after pancreatectomy for pancreatic adenocarcinoma (PDAC). We outline the following conservative perioperative strategies to optimize patient outcomes and guide the care of these patients: (1) patients with albumin < 2.5 mg/dL or weight loss > 10% should postpone surgery and begin aggressive nutrition supplementation; (2) patients with albumin < 3 mg/dL or weight loss between 5% and 10% should have nutrition supplementation prior to surgery; (3) enteral nutrition (EN) should be preferred as a nutritional intervention over total parenteral nutrition (TPN) postoperatively; and, (4) a multidisciplinary approach should be used to allow for early detection of symptoms of endocrine and exocrine pancreatic insufficiency alongside implementation of appropriate treatment to improve the patient’s quality of life.

Economic Burden of Disease-Associated Malnutrition at the State Level

Background

Disease-associated malnutrition has been identified as a prevalent condition, particularly for the elderly, which has often been overlooked in the U.S. healthcare system. The state-level burden of community-based disease-associated malnutrition is unknown and there have been limited efforts by state policy makers to identify, quantify, and address malnutrition. The objective of this study was to examine and quantify the state-level economic burden of disease-associated malnutrition.

Methods

Direct medical costs of disease-associated malnutrition were calculated for 8 diseases: Stroke, Chronic Obstructive Pulmonary Disease, Coronary Heart Failure, Breast Cancer, Dementia, Musculoskeletal Disorders, Depression, and Colorectal Cancer. National disease and malnutrition prevalence rates were estimated for subgroups defined by age, race, and sex using the National Health and Nutrition Examination Survey and the National Health Interview Survey. State prevalence of disease-associated malnutrition was estimated by combining national prevalence estimates with states’ demographic data from the U.S. Census. Direct medical cost for each state was estimated as the increased expenditures incurred as a result of malnutrition.

Principal Findings

Direct medical costs attributable to disease-associated malnutrition vary among states from an annual cost of $36 per capita in Utah to $65 per capita in Washington, D.C. Nationally the annual cost of disease-associated malnutrition is over $15.5 billion. The elderly bear a disproportionate share of this cost on both the state and national level.

Conclusions

Additional action is needed to reduce the economic impact of disease-associated malnutrition, particularly at the state level. Nutrition may be a cost-effective way to help address high health care costs.

Optimal postoperative nutrition support for patients with gastrointestinal malignancy: A systematic review and meta-analysis

OBJECTIVE

To improve clinical outcomes, parenteral nutrition, standard enteral nutrition and immuno-enhanced nutrition are widely used in the gastrointestinal tumor patients undergoing surgery, but the optimal management of postoperative nutrition support remains uncertain.

METHODS

We systematically searched the PUBMED, EMBASE and CNKI to identify latent studies which the effects of standard EN compared with PN or IEN on gastrointestinal tumor patients until the end of November, 2015. The quality of included trials was assessed according to the handbook for Cochrane reviewer. Statistical analysis was carried out by RevMan5.1 software.

RESULTS

30 randomized controlled trials containing 3854 patients were contained in our meta-analysis, the results indicated that postoperative SEN could absolutely reduce the incidence of postoperative infectious (P < 0.00001) and non-infectious complications (P = 0.0003), together with its positive effect on the length of hospital stay (P < 0.00001). Additionally, enteral nutrition enhanced with immune stimulation was confirmed to be better, with a significant difference between groups in terms of total infectious (P < 0.00001) and non-infectious complications (P = 0.04), and IEN could also significantly shorten the length of hospital stay (P < 0.00001).

CONCLUSION

Early use of Enteral nutrition in digestive tumor patients after surgery could significantly reduce the postoperative complications and shorten the length of hospital stay, IEN should be the optimal management, while the use of parenteral nutrition should be restrict to few patients with severe intolerance to enteral nutrition.

The Increasing Use of Interesterified Lipids in the Food Supply and Their Effects on Health Parameters

A variety of modified fats that provide different functionalities are used in processed foods to optimize product characteristics and nutrient composition. Partial hydrogenation results in the formation of trans FAs (TFAs) and was one of the most widely used modification processes of fats and oils. However, the negative effects of commercially produced TFAs on serum lipoproteins and risk for cardiovascular disease resulted in the Institute of Medicine and the 2010 US Dietary Guidelines for Americans both recommending that TFA intake be as low as possible. After its tentative 2013 determination that use of partially hydrogenated oils is not generally regarded as safe, the FDA released its final determination of the same in 2015. Many food technologists have turned to interesterified fat as a replacement. Interesterification rearranges FAs within and between a triglyceride molecule by use of either a chemical catalyst or an enzyme. Although there is clear utility of interesterified fats for retaining functional properties of food, the nutrition and health implications of long-term interesterified fat consumption are less well understood. The Technical Committee on Dietary Lipids of the North American Branch of the International Life Sciences Institute sponsored a workshop to discuss the health effects of interesterified fats, identify research needs, and outline considerations for the design of future studies. The consensus was that although interesterified fat production is a feasible and economically viable solution for replacing dietary TFAs, outstanding questions must be answered regarding the effects of interesterification on modifying certain aspects of lipid and glucose metabolism, inflammatory responses, hemostatic parameters, and satiety.

Pilot study evaluating the efficacy, tolerance and safety of a peptide-based enteral formula versus a high protein enteral formula in multiple ICU settings (medical, surgical, cardiothoracic)

INTRODUCTION

Predigested, peptide-based enteral formulas are commonly used to promote GI tolerance in critically ill patients, but studies comparing these against polymeric enteral formulas are lacking. We performed a prospective, randomized clinical comparison pilot study to assess safety, tolerance and effectiveness of a peptide-based enteral product.

METHODS

Critically ill patients from ICUs, including medical, surgical, and cardiothoracic, were randomized to either of two enteral feeding products: Group A: Peptide-based, high Protein, high omega-3 fat (Vital AF^®, Abbott Nutrition); Group B: high protein standard enteral formula (Osmolite^®, Abbott Nutrition). Tolerance and comorbidities as well as enteral feeding volume were collected at baseline and then daily for up to 21 days, or until the patient was discharged from the ICU.

RESULTS

A total of 49 patients were included, 25 (51%) on group A, 24 (49%) on group B. Adverse events and undesired gastrointestinal events at baseline and mean intake (ml/d and percent of goal) post baseline were not different between the groups. There were significantly fewer days with adverse events (p = 0.0336, odds ratio = 3.02, standard error = 1.60, n = 24 per group) and undesired gastrointestinal events (p = 0.0489, odds ratio = 2.79, standard error = 1.48, n = 24 per group) in group A. There was no difference in other clinical outcomes.

CONCLUSION

This pilot study suggests that feeding a peptide-based formula to ICU patients may be associated with a statistically significant reduction in the number of days during which adverse events occurred as compared to a standard formula.

Potential applications of fish oils rich in omega-3 polyunsaturated fatty acids in the management of gastrointestinal cancer

BACKGROUND & AIMS

Despite advances in chemotherapeutic agents and surgical approaches for its management, gastrointestinal cancer still accounts for 27% of new cancer cases and 35% of cancer related mortality worldwide. Omega-3 polyunsaturated fatty acids (PUFAs) specifically eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have anti-inflammatory and anticancer activities and are used as immuno-nutrients.

METHODS

A literature search was conducted to identify primary research reporting on applications of the omega-3 PUFAs in gastrointestinal cancer.

RESULTS

Reported laboratory studies indicate a clear role for omega-3 PUFAs in preventing cancer development at various stages including cancer cell proliferation, survival, angiogenesis, inflammation and metastasis. In clinical settings, omega-3 PUFAs have been reported to improve the immune response, maintain lean body mass, improve quality of life and improve overall survival in patients with colorectal and pancreatic cancer. In contrast to other GI cancers, there is a strong connection between inflammation and oesophageal cancer.

CONCLUSIONS

Little work has been done exploring the role for omega-3 PUFAs in oesophageal cancer prevention and management. The authors are conducting a clinical trial investigating the use of parenteral omega-3 PUFAs supplementary to the standard of care (epirubicin, oxaliplatin and capecitabine palliative chemotherapy) in patients with advanced oesophagogastric cancer as a promising new therapeutic approach.

Novel nutritional substrates in surgery

Pharmaco-nutrients have beneficial effects on protective and immunological mechanisms in patients undergoing surgery, which are important for recovery after injury and in combating infectious agents. The aim of this review article was to outline the potential of the administration of nutritional substrates to surgical patients and the underlying mechanisms that make them particularly important in peri-operative care. Surgery causes a stress response, which has catabolic effects on the body's substrate stores. The amino acid glutamine is a stimulating agent for immune cells. It activates protective mechanisms through its role as a precursor for antioxidants and it improves the barrier function of the gut. Arginine also enhances the function of the immune system, since it is the substrate for T-lymphocytes. Furthermore, n-3 PUFA stabilise surgery-induced hyper-inflammation. Taurine is another substrate that may counteract the negative effects of surgical injury on acid–base balance and osmotic balance. These pharmaco-nutrients rapidly become deficient under the influence of surgical stress. Supplementation of these nutrients in surgical patients may restore their protective and immune-enhancing actions and improve clinical outcome. Moreover, pre-operative fasting is still common practice in the Western world, although fasting has a negative effect on the patient's condition and the recovery after surgery. This may be counteracted by a simple intervention such as administering a carbohydrate-rich supplement just before surgery. In conclusion, there are various nutritional substrates that may be of great value in improving the condition of the surgical patient, which may be beneficial for post-operative recovery.

A systematic review on the role of fish oil for the treatment of cachexia in advanced cancer: an EPCRC cachexia guidelines project

BACKGROUND

The European Palliative Care Research Collaboration is developing clinical guidelines on cachexia in patients with advanced cancer. A systematic review on the use of fish oil/omega-3-fatty acids (n-3-FA)/eicosapentaenoic acids (EPA) in advanced cancer patients suffering from cancer cachexia was performed as part of the guideline development.

METHODS

The systematic literature search in Medline on the use of fish oil/n-3-FA/EPA identified 244 papers, with 38 publications included in the final evaluation. Some smaller trials, often unrandomized and without a control group, reported a good effect of n-3-FA in patients with advanced cancer and cachexia. However, the results of the larger randomized controlled trials could not support the positive results, as they mostly did not find a significant effect.

RESULTS

Adverse effects such as abdominal discomfort, fish belching, fish aftertaste, nausea and diarrhoea were reported with a low incidence. No serious adverse effects were documented, but adverse effects often had an impact on quality of life. This often limited dose escalations or even led to discontinuation of n-3-FA.

CONCLUSION

There is not enough evidence to support a net benefit of n-3-FA in cachexia in advanced cancer. On the other hand, adverse effects were infrequent, with no severe adverse effects. The results from the review led to a weak negative GRADE recommendation.

Fatty acids as biocompounds: their role in human metabolism, health and disease: a review. part 2: fatty acid physiological roles and applications in human health and disease

BACKGROUND

This is the second of two review parts aiming at describing the major physiological roles of fatty acids, as well as their applications in specific conditions related to human health.

RESULTS

The review included the current literature published in Pubmed up to March 2011. In humans, fatty acids are a principle energy substrate and structural components of cell membranes (phospholipids) and second messengers. Fatty acids are also ligands of nuclear receptors affecting gene expression. Longer-chain (LC) polyunsaturated fatty acids (PUFA), including eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and arachidonic acid are precursors of lipid mediators such as eicosanoids (prostaglandins, leukotrienes, thromboxanes), resolvins and neuroprotectins. Lipid mediators produced by EPA and DHA (LC n-3 PUFA; mainly found in oily fish) are considered as inflammation-resolving, and thus, fish oil has been characterised as antiinflammatory. Recommendations for EPA plus DHA intake from oily fish vary between 250-450 mg/day. Dietary reference values for fat vary between nutrition bodies, but mainly agree on a low total and saturated fat intake. The existing literature supports the protective effects of LC n-3 PUFA (as opposed to n-6 PUFA and saturated fat) in maternal and offspring health, cardiovascular health, insulin sensitivity, the metabolic syndrome, cancer, critically ill patients, and immune system disorders.

CONCLUSION

Fatty acids are involved in multiple pathways and play a major role in health. Further investigation and a nutrigenomics approach to the effects of these biocompounds on health and disease development are imperative and highlight the importance of environmental modifications on disease outcome.

n-3 PUFAs in cancer, surgery, and critical care: a systematic review on clinical effects, incorporation, and washout of oral or enteral compared with parenteral supplementation

BACKGROUND

n-3 (omega-3) Fatty acids (FAs) may have beneficial effects in patients with cancer or in patients who undergo surgery or critical care.

OBJECTIVE

Our aim was to systematically review the effects of oral or enteral and parenteral n-3 FA supplementation on clinical outcomes and to describe the incorporation of n-3 FAs into phospholipids of plasma, blood cells, and mucosal tissue and the subsequent washout in these patients.

DESIGN

We investigated the supplementation of n-3 FAs in these patients by using a systematic literature review.

RESULTS

In cancer, the oral or enteral supplementation of n-3 FAs contributed to the maintenance of body weight and quality of life but not to survival. We did not find any studies on parenteral supplementation of n-3 FAs in cancer. In surgical oncology, we did not find any studies on enteral supplementation of n-3 FAs. However, postoperative parenteral supplementation in surgical oncology may reduce the length of a hospital stay. For general surgery, we did not find any studies on enteral supplementation of n-3 FAs, and evidence on parenteral supplementation was insufficient. In critical care, enteral supplementation of n-3 FAs had beneficial effects on clinical outcomes; evidence on parenteral supplementation in critical care was inconsistent. The incorporation of n-3 FAs in plasma and blood cells was slower with enteral supplementation (4-7 d) than with parenteral supplementation (1-3 d). The washout was 5-7 d.

CONCLUSIONS

This review shows the beneficial effects of n-3 FA supplementation in cancer, surgical oncology, and critical care patients. Supplementation in these specific patient populations could be considered with the route of administration taken into account.

The optimal lipid formulation in enteral feeding in critical illness: clinical update and review of the literature

Suitable and timely early enteral nutrition is paramount to providing optimal patient care for the critically ill. Lipids serve many essential roles throughout the human body, and are important components of most enteral formulations. This paper reviews lipid structure, function, and optimal utility for this macronutrient in enteral feeds. The use of omega-3 fatty acids has become common in critical care formulations, and their clinical efficacy is outlined separately. Available evidence is reviewed, and future directions are discussed.

Potential applications of fish oils rich in n-3 fatty acids in the palliative treatment of advanced pancreatic cancer

The palliative treatment of patients with advanced pancreatic cancer (APC) has undergone little advancement in the last 15 years. Novel therapies that have been investigated to extend survival have shown little benefit over existing chemotherapy regimens. Patients with APC often experience significant weight loss, which is one of the primary factors involved in declining quality of life. Recently, the ability of n-3 fatty acid rich oral preparations to attenuate or reverse tumour-related weight loss has been investigated in this patient group with encouraging results. Laboratory investigation has also yielded promising results suggesting a potential direct tumouricidal effect of n-3 fatty acids as well as the putative potentiation of existing chemotherapy regimes. The present review aims to examine the potential applications of fish oils rich in n-3 fatty acids in patients with APC, present a selection of the studies carried out to date and outline avenues of possible further clinical investigation.

Immunonutrition in high-risk surgical patients: a systematic review and analysis of the literature

BACKGROUND

Immunomodulating diets (IMDs) have been demonstrated to improve immune function and modulate inflammation. However, the clinical benefit of these diets in patients undergoing elective surgery is controversial. The goal of this meta-analysis was to determine the impact of IMDs on the clinical outcomes of high-risk patients undergoing elective surgery.

METHODS

The review included prospective, controlled, clinical trials that compared the clinical outcome of elective surgical patients who were randomized to receive an IMD or a control enteral diet. Studies were stratified according to the type of IMD and the timing of the initiation of the IMD. Data were abstracted on study design, study size, patient population, and IMD used. The outcomes of interest were the acquisition of new infections, wound complications, length of hospital stay (LOS), and mortality. Meta-analytic techniques were used to analyze the data.

RESULTS

Twenty-one relevant studies were identified, which included a total of 1918 patients. Immunonutrition significantly reduced the risk of acquired infections, wound complications, and LOS. The mortality rate was 1% in both groups. The treatment effect was similar regardless of the timing of the commencement of the IMD. The benefits of immunonutrition required both arginine and fish oil.

CONCLUSIONS

An immunomodulating enteral diet containing increased amounts of both arginine and fish oil should be considered in all high-risk patients undergoing major surgery. Although the optimal timing cannot be determined from this study, it is suggested that immunonutrition be initiated preoperatively when feasible.

Immunonutrition in gastrointestinal surgery

BACKGROUND

Patients undergoing major gastrointestinal surgery are at increased risk of developing complications. The use of immunonutrition (IN) in such patients is not widespread because the available data are heterogeneous, and some show contradictory results with regard to complications, mortality and length of hospital stay.

METHODS

Randomized controlled trials (RCTs) published between January 1985 and September 2009 that assessed the clinical impact of perioperative enteral IN in major gastrointestinal elective surgery were included in a meta-analysis.

RESULTS

Twenty-one RCTs enrolling a total of 2730 patients were included in the meta-analysis. Twelve were considered as high-quality studies. The included studies showed significant heterogeneity with respect to patients, control groups, timing and duration of IN, which limited group analysis. IN significantly reduced overall complications when used before surgery (odds ratio (OR) 0·48, 95 per cent confidence interval (c.i.) 0·34 to 0·69), both before and after operation (OR 0·39, 0·28 to 0·54) or after surgery (OR 0·46, 0·25 to 0·84). For these three timings of IN administration, ORs of postoperative infection were 0·36 (0·24 to 0·56), 0·41 (0·28 to 0·58) and 0·53 (0·40 to 0·71) respectively. Use of IN led to a shorter hospital stay: mean difference -2·12 (95 per cent c.i. -2·97 to -1·26) days. Beneficial effects of IN were confirmed when low-quality trials were excluded. Perioperative IN had no influence on mortality (OR 0·90, 0·46 to 1·76).

CONCLUSION

Perioperative enteral IN decreases morbidity and hospital stay but not mortality after major gastrointestinal surgery; its routine use can be recommended.

Effect of a fish oil-containing beverage on changes in plasma lipid fatty acids in patients with malabsorption

BACKGROUND

The aim of this pilot study was to assess tolerance of a beverage containing ω-3 fatty acids (fish oil) in patients with malabsorption receiving chronic parenteral nutrition (PN). The authors wanted to determine whether fish oil could be absorbed and incorporated into plasma fatty acids and reduce markers of inflammation.

METHODS

This was a small intervention study in home-dwelling PN-dependent patients with chronic malabsorption. Ten patients were provided a drink containing 1.5 g of fish oil per day for 12 weeks. Baseline and post-supplement serum fatty acid profiles were compared.

RESULTS

Five of 10 patients withdrew from the study because of GI side effects, principally worsened diarrhea, associated with the supplement. Modest increases were found in 20:5ω-3, 22:5ω-3, and 22:6ω-3 levels in both phospholipids and triglycerides in plasma (all P < .05). In phospholipids, a reduced arachidonic acid level was seen (P = .02). These changes were not sufficient to effect improvements in serum tumor necrosis factor-alpha (TNFα), soluble TNF receptor, C-reactive protein, or interleukin-6.

CONCLUSIONS

Some patients with severe malabsorption can absorb oral ω-3 fatty acid supplements and incorporate these fatty acids into serum phospholipids and triglycerides. However, side effects are very common, and no anti-inflammatory effect was found, presumably related to the modest level of fatty acid change.

Oral nutritional supplements containing (n-3) polyunsaturated fatty acids affect the nutritional status of patients with stage III non-small cell lung cancer during multimodality treatment

Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), (n-3) fatty acids from fish oil, have immune-modulating effects and may improve nutritional status in cancer. The objective of this study was to investigate the effects of an oral nutritional supplement containing (n-3) fatty acids on nutritional status and inflammatory markers in patients with non-small cell lung cancer (NSCLC) undergoing multimodality treatment. In a double-blind experiment, 40 patients with stage III NSCLC were randomly assigned to receive 2 cans/d of a protein- and energy-dense oral nutritional supplement containing (n-3) fatty acids (2.0 g EPA + 0.9 g DHA/d) or an isocaloric control supplement. EPA in plasma phospholipids, energy intake, resting energy expenditure (REE), body weight, fat free mass (FFM), mid-upper arm circumference (MUAC), and inflammatory markers were assessed. Effects of intervention were analyzed by generalized estimating equations and expressed as regression coefficients (B). The intervention group (I) had a better weight maintenance than the control (C) group after 2 and 4 wk (B = 1.3 and 1.7 kg, respectively; P < 0.05), a better FFM maintenance after 3 and 5 wk (B = 1.5 and 1.9 kg, respectively; P < 0.05), a reduced REE (B = -16.7% of predicted; P = 0.01) after 3 wk, and a trend for a greater MUAC (B = 9.1; P = 0.06) and lower interleukin-6 production (B = -27.9; P = 0.08) after 5 wk. After 4 wk, the I group had a higher energy and protein intake than the C group (B = 2456 kJ/24 h, P = 0.03 and B = 25.0 g, P = 0.01, respectively). In conclusion, a protein- and energy-dense oral nutritional supplement containing (n-3) fatty acids beneficially affects nutritional status during multimodality treatment in patients with NSCLC.

Attenuation of the systemic inflammatory response and infectious complications after gastrectomy with preoperative oral arginine and omega-3 fatty acids supplemented immunonutrition

BACKGROUND

Past trials have shown perioperative immunonutrition to improve the outcome for patients with gastric cancer. The present study was designed to evaluate the effect of preoperative oral immunonutrition on cellular immunity, the duration of the systemic inflammatory response syndrome (SIRS), and detailed postoperative complications in patients with gastric cancer.

METHODS

Sixty patients with gastric cancer were randomly assigned to two groups: one group received immune-enhanced formulas supplemented with arginine and omega-3 fatty acids (immune-enhancing diet (ID) group, n = 30); the other received standard formulas (conventional diet (CD) group, n = 30) for 7 days before the operation. These groups were well matched in terms of age, sex, operations, cancer stages, and intraoperative variables. The postoperative outcome was evaluated based on clinical variables, including postoperative infectious complications, noninfectious complications, and SIRS duration. In addition, the perioperative state of cellular immunity was evaluated and compared between the two groups.

RESULTS

The incidence of postoperative infectious complications in the ID group (6%) was significantly (p < 0.05) lower than that of the CD group (28%). The duration of SIRS in the ID group (0.77 +/- 0.9 days) was significantly (p < 0.05) shorter than that in the CD group (1.34 +/- 1.45 days). The postoperative lymphocyte and CD4(+)T-cell counts significantly decreased (p < 0.05) in both groups. However, the number of CD4(+)T-cells on preoperative day 1 and postoperative day 7 was significantly (p < 0.05) higher in the ID group than in the CD group.

CONCLUSIONS

Preoperative oral immune-enhanced formulas supplemented with arginine and omega-3 fatty acids enhanced the immune status of the patients, reduced the duration of SIRS, and decreased the incidence of postoperative infectious complications. CD4(+)T-cell immunity likely played an important role in the modulation of the postoperative immune and inflammatory response after gastrectomy.

Dietary supplementation with a specific combination of high protein, leucine, and fish oil improves muscle function and daily activity in tumour-bearing cachectic mice

Cancer cachexia is characterised by metabolic alterations leading to loss of adipose tissue and lean body mass and directly compromises physical performance and the quality of life of cancer patients. In a murine cancer cachectic model, the effects of dietary supplementation with a specific combination of high protein, leucine and fish oil on weight loss, muscle function and physical activity were investigated. Male CD2F1 mice, 6–7 weeks old, were divided into body weight-matched groups: (1) control, (2) tumour-bearing, and (3) tumour-bearing receiving experimental diets. Tumours were induced by s.c. inoculation with murine colon adenocarcinoma (C26) cells. Food intake, body mass, tumour size and 24 h-activity were monitored. Then, 20 days after tumour/vehicle inoculation, the animals were killed and muscle function was tested ex vivo. Tumour-bearing mice showed reduced carcass, muscle and fat mass compared with controls. EDL muscle performance and total daily activity were impaired in the tumour-bearing mice. Addition of single nutrients resulted in no or modest effects. However, supplementation of the diet with the all-in combination of high protein, leucine and fish oil significantly reduced loss of carcass, muscle and fat mass (loss in mass 45, 52 and 65% of TB-con, respectively (P<0.02)) and improved muscle performance (loss of max force reduced to 55–64% of TB-con (P<0.05)). Moreover, total daily activity normalised after intervention with the specific nutritional combination (50% of the reduction in activity of TB-con (P<0.05)). In conclusion, a nutritional combination of high protein, leucine and fish oil reduced cachectic symptoms and improved functional performance in cancer cachectic mice. Comparison of the nutritional combination with its individual modules revealed additive effects of the single components provided.

N-3 fatty acids, cancer and cachexia: a systematic review of the literature

Use of n-3 fatty acids (FA) has been reported to be beneficial for cancer patients. We performed a systematic review of the literature in order to issue recommendations on the clinical use of n-3 FA in the cancer setting. A systematic search was performed in MEDLINE, EMBASE, Cochrane and Healthstar databases. We selected clinical trials or prospective observational studies including patients with cancer and life expectancy >2 months, in which enteral supplements with n-3 FA were administered. Parameters evaluated individually were clinical (nutritional status, tolerance, survival and hospital stays), biochemical (inflammatory mediators), and functional (functional status, appetite and quality of life (QoL)). Seventeen studies met the inclusion criteria; eight were of high quality. The panel of experts established the following evidence: (1) oral supplements with n-3 FA benefit patients with advanced cancer and weight loss, and are indicated in tumours of the upper digestive tract and pancreas; (2) the advantages observed were: increased weight and appetite, improved QoL, and reduced post-surgical morbidity; (3) there is no defined pattern for combining different n-3 FA, and it is recommended to administer > 1.5 g/day; and (4) better tolerance is obtained administering low-fat formulas for a period of at least 8 weeks. All the evidences were grade B but for 'length of treatment' and 'advantage of survival' it was grade C. Our findings suggest that administration of n-3 FA (EPA and DHA) in doses of at least 1.5 g/day for a prolonged period of time to patients with advanced cancer is associated with an improvement in clinical, biological and QoL parameters.

Beneficial effect of enteral feeding

The last 4 decades have seen an explosion in nutritional research investigating both clinical and laboratory issues occurring in diverse groups of patients who cannot maintain a normal oral diet. Over the past 25 years, researchers have investigated how the administration of macro- and micronutrients via the gastrointestinal tract provides additional benefit over parenteral administration of similar nutrients. The administration of enteral feeding provides effects that are far beyond those of merely administering macro- and micronutrients. Rather, the processing of nutrients via the gastrointestinal tract stimulates a complex response that has implications for body composition and for immunologic integrity. Route and type of nutrition are important aspects of successful patient recovery.

Immunonutrition in surgery and critical care

The benefits of specialty supplemented enteral diets administered to critically ill and critically injured patients and those undergoing major surgical procedures have been documented in a number of randomized prospective studies. It is unclear which nutrient or combination of nutrients causes the beneficial effects, but there are significant reductions in infectious complications depending upon the patient populations studied. It is imperative that the data be interpreted in the context of individual patient risk since specialty formulas appear most beneficial in patients at risk of subsequent complications or in those with significant pre-existing malnutrition. Although controversy exists regarding the use of specialty supplemented enteral diets in critically ill patients, they have been administered safely with minimal risk of adverse outcome in malnourished patients and in the critically ill and critically injured.

Effects of enteral feeding with eicosapentaenoic acid, γ-linolenic acid, and antioxidants in mechanically ventilated patients with severe sepsis and septic shock*

OBJECTIVES

Enteral diets enriched with eicosapentaenoic acid (EPA), gamma-linolenic acid (GLA), and antioxidants have previously been shown to improve outcomes in patients with acute respiratory distress syndrome. Several studies using animal models of sepsis demonstrate that enteral nutrition enriched with omega-3 fatty acids reduces mortality rate. This study investigated whether an enteral diet enriched with EPA, GLA, and antioxidant vitamins can improve outcomes and reduce 28-day all-cause mortality in patients with severe sepsis or septic shock requiring mechanical ventilation.

DESIGN

Prospective, double-blind, placebo-controlled, randomized trial.

SETTING

Three different intensive care units of a tertiary hospital in Brazil.

PATIENTS

The study enrolled 165 patients.

INTERVENTIONS

Patients were randomized to be continuously tube-fed with either a diet enriched with EPA, GLA, and elevated antioxidants or an isonitrogenous and isocaloric control diet, delivered at a constant rate to achieve a minimum of 75% of basal energy expenditure x 1.3 during a minimum of 4 days.

MEASUREMENTS AND MAIN RESULTS

Patients were monitored for 28 days. Patients who were fed with the study diet experienced a significant reduction in mortality rate compared with patients fed with the control diet, the absolute mortality reduction amounting to 19.4% (p = .037). The group who received the study diet also experienced significant improvements in oxygenation status, more ventilator-free days (13.4 +/- 1.2 vs. 5.8 +/- 1.0, p < .001), more intensive care unit (ICU)-free days (10.8 +/- 1.1 vs. 4.6 +/- 0.9, p < .001), and a lesser development of new organ dysfunctions (p < .001).

CONCLUSIONS

In patients with severe sepsis or septic shock and requiring mechanical ventilation and tolerating enteral nutrition, a diet enriched with EPA, GLA, and elevated antioxidants contributed to better ICU and hospital outcomes and was associated with lower mortality rates.

Differences in the intramolecular structure of structured oils do not affect pancreatic lipase activity in vitro or the absorption by rats of (n-3) fatty acids

The fatty acid composition and intramolecular structure of dietary triacylglycerols (TAGs) influence their absorption. We compared the in vitro pancreatic lipase activity and the lymphatic transport in rats of fish oil and 2 enzymatically interesterified oils containing 10:0 and (n-3) PUFAs of marine origin to investigate whether the positional distribution of fatty acids influenced the overall bioavailability of (n-3) PUFAs in the body. The structured oils had the (n-3) PUFA either mainly at the sn-1,3 position (LML, M = medium-chain fatty acid, L = long-chain fatty acid) or mainly at the sn-2 position (MLM). Oils were administered to lymph-cannulated rats and lymph was collected for 24 h. The fatty acid composition as well as the lipid class distribution of lymph samples was determined. In vitro pancreatic lipase activity was greater when fish oil was the substrate than when the structured oils were the substrates (P < 0.001 at 40 min). This was consistent with a greater 8-h recovery of total fatty acids from fish oil compared with the 2 structured oils (P < 0.05). The absorption profiles of MLM and LML in rats and their in vitro rates of lipase activity did not differ. This indicates that the absorption rate is highly influenced by the lipase activity, which in turn is affected by the fatty acid composition and intramolecular structure. The lipid class distribution in lymph collected from the 3 groups of rats did not differ. In conclusion, the intramolecular structure did not affect the overall absorption of (n-3) PUFAs.

Nutritional support strategies for malnourished cancer patients

A large body of evidence exists, which demonstrates the importance of nutritional support in cancer. The nutritional needs of patients with cancer may differ from those of the healthy population due to hypermetabolism, impaired organ function, increased nutrient losses and therapy-related malnutrition. Patients with cancer often have increased requirements for both macro- and micronutrients due to long periods of undernutrition prior to diagnosis. The aim of nutritional support should be the prevention or reversal of malnutrition, and this should be initiated as early as possible to improve outcomes. Oral supplementation is a simple, non-invasive method of increasing the nutrient intake of those patients who are unable to meet nutritional requirements, despite dietary counselling. Enteral tube feeding is indicated for patients who are unable to meet their nutritional needs by oral intake alone, and has been shown to improve clinical outcomes. Novel approaches in oral supplementation include the use of eicosapentaenoic acid (EPA), a compound under investigation for its role in preventing and treating cancer-associated malnutrition. Individual studies suggest that EPA attenuates cancer-associated wasting and improves immune function. In addition, it has been shown to have anti-tumour effects and improve clinical outcomes. However, results are not consistent for all patient groups and further research is required.

Cancer-associated malnutrition

Malnutrition is a common problem among patients with cancer, affecting up to 85% of patients with certain cancers (e.g. pancreas). In severe cases, malnutrition can progress to cachexia, a specific form of malnutrition characterised by loss of lean body mass, muscle wasting, and impaired immune, physical and mental function. Cancer cachexia is also associated with poor response to therapy, increased susceptibility to treatment-related adverse events, as well as poor outcome and quality of life. Cancer cachexia is a complex, multifactorial syndrome, which is thought to result from the actions of both host- and tumour-derived factors, including cytokines involved in a systemic inflammatory response to the tumour. Early intervention with nutritional supplementation has been shown to halt malnutrition, and may improve outcome in some patients. However, increasing nutritional intake is insufficient to prevent the development of cachexia, reflecting the complex pathogenesis of this condition. Nutritional supplements containing anti-inflammatory agents, for example the polyunsaturated fatty acid (PUFA) eicosapentanoic acid (EPA), have been shown to be more beneficial to malnourished patients than nutritional supplementation alone. EPA has been shown to interfere with multiple mechanisms implicated in the pathogenesis of cancer cachexia, and in clinical studies, has been associated with reversal of cachexia and improved survival.

Practical recommendations for immune-enhancing diets

Immune-enhancing diets contain nutrients that have putative benefits, including arginine, (n-3) fats, glutamine, nucleotides, and structured lipids. Although under most circumstances the systemic inflammatory response is beneficial to the host, improving the eventual outcome of injury, infection, or inflammation, excessive proinflammation (leading to cardiac, hepatic, and mitochondrial dysfunction) or excessive counterinflammation (leading to immune depression) can worsen outcome. In critically ill septic patients, the synthesis of arginine can be exceeded by its catabolism to nitric oxide (NO) and urea, rendering arginine conditionally essential. In patients with sepsis, increased production of NO increases serum nitrite and nitrate levels, whereas levels in patients with trauma and trauma with sepsis are lower than in controls. In septic patients, supplemental arginine might further increase NO levels and be potentially harmful through excessive proinflammation. However, administration of increased amounts of arginine might improve immune function in surgical and trauma patients by increasing NO production in macrophages. When the diet provides at least 1 g of the (n-3) fatty acids eicosapentaenoic and docosahexaenoic acid combined, 2-series eicosanoids (prostaglandins, prostacyclins, thromboxanes) are replaced partially by 3-series eicosanoids, and 4-series leukotrienes are replaced partially by 5-series leukotrienes that are less proinflammatory. Thus, the effects of arginine and (n-3)-fat supplementation might be expected to be complementary-arginine might improve cytokine and NO production in patients with immunodepression, whereas (n-3) fats might be beneficial when there is excessive proinflammation, particularly when supplemental arginine is supplied, by reducing cytokine-induced eicosanoid production.

Immunonutrition: problematic or problem solving?

The addition of immune-modulating nutrients to enteral formulas has been examined in clinical trials and meta-analyses. Enhancing immunity through diet is generally done by adding n-3 fatty acids, arginine, and nucleotides to an otherwise nutritionally complete formula. Despite flaws in many studies, a consistent trend to reduced infectious complications has been seen with immunonutrition, especially in patients undergoing surgery for upper gastrointestinal cancer or trauma. In critical care populations, however, the results have been mixed. In this review, we analyze these studies and focus on select clinical points that may explain the variation. One common flaw has been a failure to deliver an adequate nutrition volume. Few patients, especially in the earliest studies, received even close to goal feeding. A minimum quantity of immunonutrition may be required for effective reduction in infections. When feeding volumes are low, immunonutrition is usually not better than an isonitrogenous control. In more recent studies, practitioners have been increasingly aggressive with enteral feeding, and this has been reflected in improved outcomes from immunonutrition. Early delivery of immunonutrition (preoperatively in surgical patients with cancer) might be particularly beneficial. Another consideration is illness severity: we discuss evidence that the use of immunonutrition in moderate illness is more likely to be helpful, whereas severe sepsis is probably beyond the reach of any nutritional intervention, and mild illness is more likely to improve irrespective of feeding. If future trials can consider these vital points, level 1 recommendations in favor of immunonutrition might be justified, although presently such evidence is lacking for most clinical indications.

Enteral nutrition with eicosapentaenoic acid, gamma-linolenic acid, and antioxidants reduces alveolar inflammatory mediators and protein influx in patients with acute respiratory distress syndrome

OBJECTIVE

Previously, we showed that acute respiratory distress syndrome patients fed an enteral diet containing eicosapentaenoic acid and gamma-linolenic acid and elevated antioxidants (EPA+GLA; Oxepa) had significantly reduced pulmonary inflammation, increased oxygenation, and improved clinical outcomes. In a subset of acute respiratory distress syndrome patients from this trial, we performed a preliminary examination of the potential mechanisms underlying these clinical improvements by retrospectively testing the hypothesis that enteral feeding with EPA+GLA could reduce alveolar-capillary membrane protein permeability and the production of interleukin (IL)-8, IL-6, tumor necrosis factor-alpha, and leukotriene B4 that are responsible, in part, for pulmonary inflammation.

DESIGN

Prospective, randomized, double-blind, controlled clinical trial.

SETTING

Intensive Care Unit of the Ohio State University Medical Center.

PATIENTS

A total of 67 patients were enrolled who met defined criteria for acute lung injury/acute respiratory distress syndrome.

INTERVENTIONS

A total of 43 of 67 evaluable patients randomly received either EPA+GLA or an isonitrogenous, isocaloric standard diet that was tube fed at a minimum caloric delivery of 75% of basal energy expenditure times 1.33 for at least 4 to 7 days.

MEASUREMENTS AND MAIN RESULTS

Bronchoalveolar lavage (BAL) was performed at baseline and study days 4 and 7 to obtain BAL fluid (BALF) for measurement of total protein, ceruloplasmin, and transferrin, total neutrophil count, IL-8, IL-6, tumor necrosis factor-alpha, and leukotriene B4. Oxygenation, measured as Pao2/Fio2, was assessed before BAL. Patients fed EPA+GLA had a significant reduction in BALF ceruloplasmin and IL-8 during the study as compared with patients fed the control diet. BALF levels of total protein, neutrophils, and leukotriene B4 tended to decrease in EPA+GLA patients over the course of the study as compared with control patients. BALF levels of IL-6 declined similarly during the study in both groups. A trend toward a reduction in BALF tumor necrosis factor-alpha was observed on study day 7 in the EPA+GLA group as compared with control patients. Significant improvements in oxygenation (Pao2/Fio2) occurred in EPA+GLA patients on study day 4 as compared with controls. Correlation analysis revealed significant relationships between BALF neutrophil counts and indices of alveolar-capillary membrane protein permeability, IL-8, and leukotriene B4.

CONCLUSIONS

This preliminary investigation showing a decrease in BALF levels of IL-8 and leukotriene B4 and the associated reduction of BALF neutrophils and alveolar membrane protein permeability in acute respiratory distress syndrome patients fed EPA+GLA support, in part, the potential mechanisms underlying the previously described clinical improvements with this diet. Additional controlled studies are needed to confirm these findings.

Preoperative oral arginine and n-3 fatty acid supplementation improves the immunometabolic host response and outcome after colorectal resection for cancer

BACKGROUND

Previous trials showed that perioperative immunonutrition improved outcome in patients with gastrointestinal cancer. This study was designed to appraise the impact of the simple preoperative oral arginine and n-3 fatty acids supplementation on immune response, gut oxygenation, and postoperative infections.

METHODS

Two hundred patients with colorectal neoplasm were randomized to: (a) oral intake for 5 days before surgery of a formula enriched with arginine and n-3 fatty acids (pre-op group; n = 50); (b) same preoperative treatment prolonged after surgery by jejunal infusion (peri-op group; n = 50); (c) oral intake for 5 days before surgery of a standard isoenergetic, isonitrogenous formula (control group; n = 50); and (d) no supplementation before and after operation (conventional group; n = 50). The immune response was measured by phagocytosis ability of polymorphonuclear cells and delayed hypersensitivity response to skin tests. Gut oxygenation and microperfusion were assessed by polarographic probes and laser Doppler flowmetry, respectively.

RESULTS

The 4 groups were comparable for demographics, comorbidity, and surgical variables. The 2 groups receiving immunoutrients (pre-op and peri-op) had a significantly better immune response, gut oxygenation, and microperfusion than the other 2 groups. Intent-to-treat analysis showed an overall infection rate of 12% in pre-op, 10% in peri-op, 32% in control, and 30% in conventional groups (P <.04 pre-op and peri-op vs control and conventional).

CONCLUSION

Preoperative oral arginine and n-fatty acids improves the immunometabolic response and decreases the infection rate. Postoperative prolongation with such supplemented formula has no additional benefit.

Structured Lipids-Novel Fats with Medical, Nutraceutical, and Food Applications

Generally, structured lipids (SLs) are triacylglycerols (TAGs) that have been modified to change the fatty acid composition and/or their positional distribution in glycerol backbone by chemically and/or enzymatically catalyzed reactions and/or genetic engineering. More specifically, SLs are modified TAGs with improved nutritional or functional properties. SLs provide an effective means for producing tailor-made lipids with desired physical characteristics, chemical properties, and/or nutritional benefits. The production, commercialization outlook, medical, and food applications of SLs are reviewed here. Physical property measurements for SL in food systems and future research needs for increased industrial acceptance are also included in this review.

Nutrition and gastrointestinal cancer

The present review addresses data from randomized clinical trials on perioperative nutrition in patients with gastrointestinal cancer. It is important to appreciate that different approaches can be used with regard to timing of administration of nutritional support (preoperative versus postoperative), route of administration (parenteral versus enteral) and composition of the admixtures given (standard versus immune-enriched diets). The rationale underlying these approaches may also vary, and may include correction of nutritional status, attenuation of the acute-phase response through better preservation of gut function, and potentiation of the immune response.