Current Opinion in Clinical Nutrition and Metabolic Care最新文献

Purpose of review: This review aims to summarize recent studies that highlight the complex relationship between nutrition, carbohydrate, insulin provision and glycaemic control in the critically ill patient population.

Recent findings: Results of observational studies concur to support early hypoglycaemia and persisting hyperglycaemia as life-threatening events. In contrast, interventional studies indicate that early macronutrient restriction appears to reduce the benefits related to insulin therapy. This restriction is however associated with improved outcomes in itself. The potential role of modified enteral solutions as an adjunctive treatment to attenuate hyperglycaemia warrants further research. The selection of a therapeutic modality may also differ according to the characteristics of the setting, such as the nurse-to-patient ratio, the type and accuracy of meters, including near-continuous glucose monitoring and the availability of computer-guided protocols.

Summary: There appears to be significant interplay between nutrition, including carbohydrate provision, blood glucose control and clinical outcomes. Individualized care is probably needed to define the optimal glucose target and nutritional intervention. This can differ according to the preexistence of chronic hyperglycaemia, the timing from the onset of critical illness and the clinical condition itself.

Purpose of review: This review will summarize recent studies assessing the effect of slowly digestible starch (SDS) and resistant starch (RS) on glucose metabolism in healthy, prediabetic or type 2 diabetic adults.

Recent findings: Currently, a particular interest in starch and its digestibility has arisen, with data showing a positive effect of SDS and RS on the glucose homeostasis of healthy, at-risk, prediabetic and type 2 diabetic patients but research is ongoing.

Summary: Carbohydrates (CHO) and especially starch play a major role in the prevention and management of metabolic diseases such as type 2 diabetes (T2D). This largely depends on the quality and the digestibility (rate and extent) of the ingested starchy products, beyond their quantity. SDS have been poorly studied but display a beneficial effect on reducing glucose excursions in healthy and insulin-resistant subjects and a relevant potential to improve glucose control in type 2 diabetic individuals. As for RS, the results appear to be encouraging but remain heterogeneous, depending the nature of the RS and its role on microbiota modulation. Further studies are needed to confirm the present results and investigate the potential complementary beneficial effects of SDS and RS on long-term glucose homeostasis to prevent cardiometabolic diseases.

Purpose of review: Recommendations on the use of nonsugar sweeteners are contradictory, even if they come from official sources. The aim is to review and discuss recent findings on the potential impact of nonsugar sweeteners on human health.

Recent findings: While randomized controlled trials (RCTs) with short duration and risk factors endpoints mostly show favourable effects on body weight and cardiometabolic parameters when nonsugar sweeteners are used to replaced sugar-sweetened products, observational studies mostly show a positive association between the consumption of nonsugar sweeteners and cardiometabolic diseases. The conflicting results may be explained by the heterogenous nature of nonsugar sweeteners but also likely is a consequence of serious weaknesses of available studies.

Summary: For more evidence-based recommendations for practice and policy, scientifically sound studies with long follow-up are required.

Purpose of review: Sarcopenic obesity is a newly identified pathological entity defined by an increase in body fat mass with an associated sarcopenia, characterized by loss of muscle mass, strength, and function. Recently, the concomitant presence of skeletal alteration with sarcopenic obesity has been described leading to a new clinical entity defined osteosarcopenic obesity (OSO). Many studies have tried to unravel the metabolic complex mechanism leading to this clinical entity in order to understand the pathophysiology of this complex condition with the aim of posing an early diagnosis to improve the therapeutic approaches. The purpose of this narrative review is to highlight and revise recent studies on this issue.

Recent findings: Recent research in the field of OSO has highlighted the role of nutrition and physical activity in the development and management of these conditions. While molecular and cellular pathways remain partially understood, there is a growing focus on lifestyle interventions as key factors in reducing the impact of OSO. These studies emphasize the need for early diagnosis and appropriate therapeutic strategies to improve quality of life and decrease morbidity and mortality associated with OSO.

Summary: Although the pathophysiological pathways underlying OSO are not fully understood, the clinical implications underscore the need for expanded research in this field. This research is crucial for enabling early diagnosis and implementing effective therapeutic interventions, with the goal of reducing morbidity and mortality and enhancing quality of life.

Purpose of review: Diets low in animal-source foods or solely consisting of plant-based foods, hardly meet nutrition needs of children, exposing them to inadequate intake of essential nutrients. Thus, including edible insects in children's diets is relevant for meeting nutritional requirements, other potential health benefits, and building more sustainable food systems. Nutrition and health research on insects is novel and still limited. This review covers recently published research between April 2022 and November 2023 focusing on the relevance of including insects in children's diets.

Recent findings: Insects provide protein, fat and micronutrients, and are generally nutritionally equivalent to animal-source foods. The protein and fat quality of edible insects varies depending on several factors. Insects also contain chitin which could potentially be beneficial for gut health. For insects to be considered suitable for inclusion in children's diet, they must be accepted. However, children who are unfamiliar with insects respond to them with curiosity and disgust.

Summary: Insect farming can enhance their availability and consumption, potentially addressing nutrition gaps. Furthermore, transitioning from occasional to regular insect consumption requires actual exposure and integration into diets of insects. To affirm the nutrition and health potential of edible insects for children, well designed human studies are essential.

Purpose of review: To describe the role of Tryptophan (Trp) metabolism and Kynurenine (Kyn) metabolites in nutritional and metabolic changes in cancer.

Recent findings: Trp is in part utilized for protein and neurotransmitters biosynthesis, but more than 95% is implicated in Kyn pathways. In this molecular cascade, metabolites are produced with distinct biological activities regulating the immune response and neurotransmission with potential implications in malnutrition/cachexia during cancer. Immune dysfunction is a phenomenon occurring during cancer and malnutrition. Kyn metabolites regulate lymphocytes activity and recent data in animals showed that the inhibition of indoleamine-2,3-dioxygenase (IDO) via 1-methyl-tryptophan determines partial amelioration of inflammation, but no positive effects on the preservation of muscularity were observed. Kynurenines seem to contribute to muscle catabolism via NAD+ biosynthesis and ROS generation. Trp metabolism via the serotonin biosynthesis is involved in appetite control in cancer. Moreover, kynurenines have a role in determining fatigue in conditions associated with inflammation.

Summary: Trp metabolism has implications in immune and energy balance in cancer. The modulation of Trp and kynurenines have impact on central nervous system mechanisms, including appetite, fatigue, and muscle wasting/cachexia. Research focusing on these clinical implications will open new scenario for therapeutic interventions aimed at counteracting nutritional derangements in cancer.

Purpose of review: To discuss the recent discoveries and limitations of the available literature on emerging circulating biomarkers of cancer cachexia.

Recent findings: Studies on circulating factors in cancer cachexia show promising alternatives for diagnosing the syndrome in a minimally invasive manner in the clinic setting, as well as potential targets for cancer cachexia treatment. Factors secreted by the tumor and the adipose tissue, such as extracellular vesicles and soluble proteins, respectively, have been shown to either directly induce wasting in vitro and in vivo or to be altered in the cachectic phenotype. The detection and characterization of circulating cells allows detection of the precachectic stage and the levels of the soluble immune checkpoint protein programmed death ligand-1 (PD-L1) are correlated with the presence of the hallmarks of cancer cachexia.

Summary: Structural, molecular, and metabolic alterations have been observed in various tissues, revealing the occurrence of sustained inter-compartment crosstalk in cachectic patients. Early diagnosis of cancer cachexia becomes crucial to avoid the establishment of refractory cachexia through the implementation of interventions that may attenuate systemic inflammation and muscle loss. More studies on human cancer cachexia are required in order to address the recently discovered cachexia-associated circulating factors' value as biomarkers of the syndrome.

Purpose of review: This article provides a literature update on original articles published in the past 18 months (May 2022-November 2023) in the dietary management of paediatric Crohn's disease.

Recent findings: There is more data to support the use of exclusive enteral nutrition in the management of active Crohn's disease in children. Several food-based dietary therapies have been proposed for the management of Crohn's disease. There is an interest in precision nutritional therapy in Crohn's disease, but current data are scarce.

Summary: Exclusive enteral nutrition is an effective treatment for paediatric Crohn's disease. Predictors of response to exclusive enteral nutrition include mild disease phenotype and ileal disease involvement, although data remain inconclusive. Adherence to exclusive enteral nutrition is cornerstone to its efficacy. Treatment with exclusive enteral nutrition modifies the gut microbiome, modulates bile acid metabolism and has significant effects on host immune responses. More studies are expected in which drugs need to be combined with dietary therapies and microbial therapeutics. The efficacy of Crohn's disease exclusion diet coupled with partial enteral nutrition is supported by independent studies, but tolerance remains an issue, particularly for long-term disease management. More research is anticipated in precision nutritional therapy in paediatric Crohn's disease, but currently no recommendations can be made.

Purpose of review: Renal cachexia is a deleterious condition characterized by weight loss, muscle wasting and loss of physical function, quality of life, and increased mortality. Multimodal treatment strategies utilizing exercise and nutrition interventions have been recently suggested although the evidence base is still in its infancy. This paper aimed to review the current literature surrounding the use of exercise and nutrition for renal cachexia.

Main findings: Evidence from systematic reviews and narrative reviews indicates that resistance training (RT) is proven to have beneficial effects on improving muscle strength and in some cases physical function, although effects on muscle mass are mixed and inconclusive. Further, combined RT and aerobic training (AT) may have also beneficial effects on overall functional capacity and there appears to be no superior mode of protocol (inter/intra-dialysis vs. home-based). For nutrition, there is new data from systematic review of studies indicating that oral nutritional supplementation (ONS) may have beneficial effects on nutritional status (e.g. body mass index, plasma albumin and handgrip strength). Omega-3 fatty acids have been shown to have anti-inflammatory effects in haemodialysis patients from two recent systematic reviews, and evidence from other populations groups indicate they may be beneficial for improving muscle mass and strength.

Summary: Evidence is accumulating for individual exercise and nutrition components but specific multimodal treatment studies in renal cachexia need to be urgently undertaken.

Purpose of review: Sarcopenia is a wasting disease, mostly age-related in which muscle strength and mass decline, such as physical performance. With aging, both lower dietary protein intake and anabolic resistance lead to sarcopenia. Moreover, aging and sarcopenia display low-grade inflammation, which also worsen muscle condition. In this review, we focused on these two main targets to study dietary strategies.

Recent findings: The better understanding in mechanisms involved in sarcopenia helps building combined dietary approaches including physical activity that would slow the disease progression. New approaches include better understanding in the choice of quality proteins, their amount and schedule and the association with antioxidative nutrients.

Summary: First, anabolic resistance can be countered by increasing significantly protein intake. If increasing amount remains insufficient, the evenly delivery protein schedule provides interesting results on muscle strength. Quality of protein is also to consider for decreasing risk for sarcopenia, because varying sources of proteins appears relevant with increasing plant-based proteins ratio. Although new techniques have been developed, as plant-based proteins display a lower availability, we need to ensure an adapted overall amount of proteins. Finally, specific enrichment with leucine from whey protein remains the dietary combined approach most studied and studies on citrulline provide interesting results. As cofactor at the edge between anabolic and antioxidative properties, vitamin D supplementation is to recommend. Antioxidative dietary strategies include both fibers, vitamins, micronutrients and polyphenols from various sources for positive effects on physical performance. The ω 3 -polyunsaturated fatty acids also display positive modifications on body composition. Gut microbiota modifiers, such as prebiotics, are promising pathways to improve muscle mass and function and body composition in sarcopenic patients. Nutritional interventions could be enhanced by combination with physical activity on sarcopenia. In healthy older adults, promoting change in lifestyle to get near a Mediterranean diet could be one of the best options. In sarcopenia adults in which lifestyle changes appears unprobable, specific enrichement potentialized with physical activity will help in the struggle against sarcopenia. Longitudinal data are lacking, which makes it hard to draw strong conclusions. However, the effects of a physical activity combined with a set of nutrition interventions on sarcopenia seems promising.