Elemental diets have been employed for the management of various diseases for over 50 years, with several mechanisms mediating their beneficial effects. Yet, they are underutilized due to poor palatability, access, cost, and lack of awareness regarding their clinical efficacy. Therefore, in this review, we aimed to systematically search and review the literature to summarize the formulation variability, mechanisms of action, clinical applications, and tolerability of the elemental diets in gastrointestinal diseases. While large prospective trials are lacking, elemental diets appear to exhibit objective and subjective clinical benefit in several diseases, including eosinophilic esophagitis, eosinophilic gastroenteritis, inflammatory bowel diseases, small intestinal bacterial overgrowth, intestinal methanogen overgrowth, chemoradiotherapy-associated mucositis, and celiac disease. Although some data support the long-term use of elemental diets as an add-on supplement for chronic pancreatitis and Crohn\'s disease, most of the literature on exclusive elemental diets focuses on inducing remission. Therefore, subsequent treatment strategies for maintaining remission need to be adopted in chronic/relapsing diseases. Several mechanistic pathways were identified to mediate the effects of elemental diets, including food additive and allergen-free content, high passive absorption rate, and anti-inflammatory properties. High rates of intolerance up to 40% are seen in the trials where exclusive elemental diets were administered orally due to poor organoleptic acceptability; however, when tolerated, adverse events were rare. Other limitations of elemental diets are cost, access, and lifestyle/social restrictions. Moreover, judicious use is advised in presence of a concomitant restrictive food intake disorders. Elemental diets offer a potentially highly efficacious dietary intervention with minor side effects. Palatability, cost, access, and social restrictions are common barriers of use. Prospective clinical trials are needed to elucidate the role of elemental formulas in the management of individual diseases.

OBJECTIVE: Gastric tube feeding and postpyloric tube feeding are two common forms of enteral nutrition in critically ill patients. This study aimed to compare the efficacy and safety of gastric tube feeding with that of postpyloric tube feeding in critically ill patients.
METHODS: PubMed, Embase, and Cochrane Library were systematically searched for eligible trials from their inception until March 2023. Relative risks (RRs) or weighted mean differences (WMDs) with 95% confidence intervals (CIs) were used to estimate categorical and continuous outcomes using the random-effects model.
RESULTS: Sixteen trials involving 1,329 critically ill patients were selected for the final meta-analysis. Overall, we noted that gastric tube feeding showed no significant difference from post-pyloric tube feeding in mortality (p = 0.891), whereas the risk of pneumonia was significantly increased in patients who received gastric tube feeding (RR: 1.45; p = 0.021). Furthermore, we noted that gastric tube feeding was associated with a shorter time required to start feeding (WMD: -11.05; p = 0.007).
CONCLUSIONS: This research revealed that initiating feeding through the gastric tube required less time compared to postpyloric tube feeding. However, it was also associated with a heightened risk of pneumonia among critically ill patients.

BACKGROUND: The primary objective of this study is to comparatively assess the safety of nasogastric (NG) feeding versus nasojejunal (NJ) feeding in patients with acute pancreatitis (AP), with a special focus on the initiation of these feeding methods within the first 48 h of hospital admission.
METHODS: Studies were identified through a systematic search in PubMed, EMbase, Cochrane Central Register of Controlled Trials, and Web of Science. Four studies involving 217 patients were included. This systematic review assesses the safety and efficacy of nasogastric versus nasojejunal feeding initiated within 48 h post-admission in moderate/severe acute pancreatitis, with a specific focus on the timing of initiation and patient age as influential factors.
RESULTS: The results showed that the mortality rates were similar between NG and NJ feeding groups (RR 0.86, 95% CI 0.42 to 1.77, P = 0.68). Significant differences were observed in the incidence of diarrhea (RR 2.75, 95% CI 1.21 to 6.25, P = 0.02) and pain (RR 2.91, 95% CI 1.50 to 5.64, P = 0.002) in the NG group. The NG group also showed a higher probability of infection (6.67% vs. 3.33%, P = 0.027) and a higher frequency of multiple organ failures. Subgroup analysis for early intervention (within 48 h) showed a higher risk of diarrhea in the NG group (RR 2.80, P = 0.02). No significant differences were found in the need for surgical intervention, parenteral nutrition, or success rates of feeding procedures.
CONCLUSIONS: This meta-analysis highlights the importance of considering the method and timing of nutritional support in acute pancreatitis. While NG feeding within 48 h of admission increases the risk of certain complications such as diarrhea and infection, it does not significantly impact mortality or the need for surgical intervention.

OBJECTIVE: Medical nutrition therapy provides the opportunity to compensate for muscle wasting and immune response activation during stress and trauma. The objective of this systematic review is to assess the safety and effectiveness of early enteral nutrition (EEN) in adults with sepsis or septic shock.
METHODS: The MEDLINE, Embase, CENTRAL, CINAHL, ClinicalTrials.gov, and ICTRP tools were searched from inception until July 2023. Conference proceedings, the reference lists of included studies, and expert content were queried to identify additional publications. Two review authors completed the study selection, data extraction, and risk of bias assessment; disagreements were resolved through discussion. Inclusion criteria were randomized controlled trials (RCTs) and non-randomized studies (NRSs) comparing the administration of EEN with no or delayed enteral nutrition (DEE) in adult populations with sepsis or septic shock.
RESULTS: Five RCTs (n = 442 participants) and ten NRSs (n = 3724 participants) were included. Low-certainty evidence from RCTs and NRSs suggests that patients receiving EEN could require fewer days of mechanical ventilation (MD -2.65; 95% CI, -4.44-0.86; and MD -2.94; 95% CI, -3.64--2.23, respectively) and may show lower SOFA scores during follow-up (MD -1.64 points; 95% CI, -2.60--0.68; and MD -1.08 points; 95% CI, -1.90--0.26, respectively), albeit with an increased frequency of diarrhea episodes (OR 2.23, 95% CI 1.115-4.34). Even though the patients with EEN show a lower in-hospital mortality rate both in RCTs (OR 0.69; 95% CI, 0.39-1.23) and NRSs (OR 0.89; 95% CI, 0.69-1.13), this difference does not achieve statistical significance. There were no apparent differences for other outcomes.
CONCLUSIONS: Low-quality evidence suggests that EEN may be a safe and effective intervention for the management of critically ill patients with sepsis or septic shock.

BACKGROUND: Acute nutrition-related adverse outcomes are common in head and neck cancer patients undergoing radiotherapy. Predictive models can assist in identifying high-risk patients to enable targeted intervention. We aimed to systematically evaluate predictive models for predicting severe acute nutritional symptoms, insufficient intake, tube feeding, sarcopenia, and weight loss.
METHODS: We searched PubMed, Web of Science, EBSCO, Embase, WanFang, CNKI, and SinoMed. We selected studies developing predictive models for the aforementioned outcomes. Data were extracted using a predefined checklist. Risk of bias and applicability assessment were assessed using the Prediction model Risk of Bias Assessment Tool. A narrative synthesis was conducted to summarize the model characteristics, risk of bias, and performance.
RESULTS: A total of 2941 studies were retrieved and 19 were included. Study outcome measure were different symptoms (n = 11), weight loss (n = 5), tube feeding (n = 3), and symptom or tube feeding (n = 1). Predictive factors mainly encompassed sociodemographic data, disease-related data, and treatment-related data. Seventeen studies reported area under the curve or C-index values ranging from 0.610 to 0.96, indicating moderate to good predictive performance. However, candidate predictors were incomplete, outcome measures were diverse, and the risk of bias was high. Most of them used traditional model development methods, and only two used machine learning.
CONCLUSIONS: Most current models showed moderate to good predictive performance. However, predictors are incomplete, outcome are inconsistent, and the risk of bias is high. Clinicians could carefully select the models with better model performance from the available models according to their actual conditions. Future research should include comprehensive and modifiable indicators and prioritize well-designed and reported studies for model development.

International guidelines recommend a target protein intake of ≥1.2 g/kg/day to all critically ill patients for optimal outcomes. There are however various conflicting data related to this recommendation. The primary objective of this review was to compare a protein intake group (≥1.2 g/kg/day) with a lower protein intake group (<1.2 g/kg/day) in critically ill adult patients on mortality, length of intensive care unit (ICU) and hospital stay. Secondly, the effect of protein intake on length of mechanical ventilation, adverse nutrition-related events and muscle mass and strength parameters were investigated. Sixteen randomised controlled trials (RCTs) of adult patients admitted to an intensive or high care unit and receiving nutrition support in the form of enteral- and/or parenteral nutrition were selected against prespecified eligibility criteria. Two independent reviewers extracted relevant data and assessed the risk of bias of the included studies. Review Manager 5.4.1 was used to analyse data and GRADE (Grading of Recommendations, Assessment, Development, and Evaluations) was used to evaluate the certainty of the evidence. The higher protein group, when compared to the lower protein group, probably results in little to no difference in mortality (risk ratio [RR] 1.01; 95% confidence interval [CI]: 0.89 to 1.14; moderate-certainty evidence); with a probable slight increase in length of ICU stay (mean difference [MD] 0.33; 95% CI -0.57 to 1.23; moderate-certainty) and length of hospital stay (MD 1.72; 95% CI -0.58 to 4.01; moderate-certainty evidence), on average. For secondary outcomes, it was found that the higher protein group probably does not reduce the length of mechanical ventilation (MD 0.08; 95% CI -0.38 to 0.53; moderate-certainty evidence). Higher protein group probably reduces the occurrence of diarrhoea and high gastric residual volume and may reduce the occurrence of constipation. It may also increase nitrogen balance (MD 3.66; 95% CI 1.81 to 5.51; low-certainty evidence). Importantly, there does not seem to be harm associated with the higher protein group, though it should be mentioned that for many of the adverse events in this study, the certainty of evidence was low or very low.

BACKGROUND: Taurine is considered an immunomodulatory agent. From current reports on clinical studies, we conducted a systematic review and meta-analysis to investigate the effects of taurine-enhanced enteral nutrition (EN) on the outcomes of critically ill patients to resolve conflicting evidence in literature.
METHODS: Literature from PubMed, EMBASE, Web of Science, Cochrane Library, CNKI, SINOMED, and WanFang databases were retrieved, and randomized controlled trials (RCTs) were identified. The time range spanned from January 1, 2000, to January 31, 2024. The Cochrane Collaboration Tool was used to evaluate the risk of bias. We used the GRADE approach to rate the quality of evidence and the I2 test to assess the statistical heterogeneity of the results. Risk ratio (RR), mean difference (MD), and 95% confidence interval (95% CI) were used to analyze measurement data.
RESULTS: Four trials involving 236 patients were finally included. The meta-analysis results indicated that taurine-enhanced EN did not reduce mortality (RR = 0.70, p = 0.45, 95% CI [0.28, 1.80], two trials, 176 participants, low quality). There was also no significant difference in length of stay in the intensive care unit (ICU) between the taurine-enhanced EN and control groups. Taurine-enhanced EN may reduce pro-inflammatory factor interleukin-6 (IL-6) levels in critically ill patients（the result about IL-6 cannot be pooled）. However, taurine-enhanced EN had no significant impact on high-sensitivity-C-reactive protein levels (MD = -0.41, p = 0.40, 95% CI [-1.35, 0.54], two trials, 60 participants, low quality).
CONCLUSIONS: Taurine-enhanced EN may reduce IL-6 levels and is not associated with improved clinical outcomes in critically ill patients, which may have potential immunoregulatory effects in critically ill patients. Given that published studies have small samples, the above conclusions need to be verified by more rigorously designed large-sample clinical trials.

Obesity is a challenging chronic disease process that continues to affect a large percentage of the population at large. With the advent of new therapeutic options and interventions and a deeper scientific understanding of obesity as a complex illness, there is hope in curtailing this evolving pandemic. In this article, we present key medical information to engage and empower nutrition-focused providers to manage obesity and its nutrition complications. The topics summarized here were presented during the 2023 American Society for Parenteral and Enteral Nutrition Preconference Physician Course and include pathophysiology and hormonal regulation of obesity, multidisciplinary care planning and nutrition risk stratification of patients, and common approaches to treatment, including lifestyle modifications, antiobesity medications, and procedures from the perspective of the nutrition specialist.

Congenital diarrheas and enteropathies (CODE) are a group of rare, heterogenous, monogenic disorders that lead to chronic diarrhea in infancy. Definitive treatment is rarely available, and supportive treatment is the mainstay. Nutritional management in the form of either specialized formulas, restrictive diet, or parenteral nutrition support in CODE with poor enteral tolerance is the cornerstone of CODE treatment and long-term growth. The evidence to support the use of specific diet regimens and nutritional approaches in most CODE disorders is limited due to the rarity of these diseases and the scant published clinical experience. The goal of this review was to create a comprehensive guide for nutritional management in CODE, based on the currently available literature, disease mechanism, and the PediCODE group experience. Enteral diet management in CODE can be divided into 3 distinct conceptual frameworks: nutrient elimination, nutrient supplementation, and generalized nutrient restriction. Response to nutrient elimination or supplementation can lead to resolution or significant improvement in the chronic diarrhea of CODE and resumption of normal growth. This pattern can be seen in CODE due to carbohydrate malabsorption, defects in fat absorption, and occasionally in electrolyte transport defects. In contrast, general diet restriction is mainly supportive. However, occasionally it allows parenteral nutrition weaning or reduction over time, mainly in enteroendocrine defects and rarely in epithelial trafficking and polarity defects. Further research is required to better elucidate the role of diet in the treatment of CODE and the appropriate diet management for each disease.

UNASSIGNED: Enteral nutrition is a very important form of treatment for critically ill patients. This meta-analysis aimed to evaluate the clinical effects and safety of semi-solid feeds in tube-fed patients.
UNASSIGNED: Two researchers searched PubMed, clinical trials, Embase, Cochrane Central Register of Controlled Trials, Web of Science, Cochrane Library, China National Knowledge Infrastructure (CNKI), Wanfang Data, and Weipu databases for randomized controlled trials (RCTs) on the clinical effects and safety of semi-solid feeds in tube-fed patients until 10 October 2023. The quality evaluation tool recommended by the Cochrane Library was used to evaluate the quality of included RCTs. RevMan 5.4 software was used for data analysis.
UNASSIGNED: A total of eight RCTs involving 823 tube-fed patients were included in this meta-analysis. A synthesized outcome indicated that semi-solid feeds reduced the incidence of diarrhea (RR = 0.32, 95%CI:0.20-0.50, P < 0.001), vomiting (RR = 0.31, 95%CI:0.15-0.64, P = 0.002), abdominal distension (RR = 0.41, 95%CI:0.22-0.76, P = 0.005), length of intensive care unit (ICU) stay (MD = -3.61, 95%CI: -6.74 to -0.48, P = 0.02), and length of hospital stay (MD = -7.14, 95%CI: -10.31 to -3.97, P < 0.01) in tube-fed patients. Enteric feeding had no effect on the 30-day mortality (RR = 0.55, 95%CI: 0.19-1.56, P = 0.26). No publication bias was detected by the Egger\'s test results (all P > 0.05).
UNASSIGNED: Semi-solid feeds are beneficial in reducing the incidence of diarrhea, abdominal distension, vomiting, and hospital stay. More high-quality studies are needed in the future to verify the effects of semi-solid feeds on mortality.