Introducing orange sweet potato: tracing the evolution of evidence on its effectiveness

The introduction of orange sweet potato (OSP), rich in vitamin A, can have important and lasting impacts on reducing vitamin A deficiency among smallholder farmers in the developing world. In this paper, we describe the evolution of evidence about the effectiveness of disseminating OSP to smallholder farmers on vitamin A deficiency. We trace projects from a small trial in 10 villages in western Kenya through the Reaching End Users program in Mozambique and Uganda that reached thousands of households in both countries, while demonstrating that households receiving integrated programs teaching them to grow OSP and the nutritional benefits of vitamin A had notable impacts on the probability of vitamin A deficiency and on biological markers for vitamin A in women of child-bearing age and young children, relative to members of households not selected for participation. The evidence generated through research has played an important role in efforts to disseminate the crop more widely, and future evaluations will help build understanding about how OSP can be combined with other interventions, such as health visits or disseminating additional biofortified foods.Keywords: Orange Sweet Potato, Vitamin A, Impact Evaluation, Biofortificatio

Metrics to analyze and improve diets through food Systems in low and Middle Income Countries

Taking a food systems approach is a promising strategy for improving diets. Implementing such an approach would require the use of a comprehensive set of metrics to characterize food systems, set meaningful goals, track food system performance, and evaluate the impacts of food system interventions. Food system metrics are also useful to structure debates and communicate to policy makers and the general public. This paper provides an updated analytical framework of food systems and uses this to identify systematically relevant metrics and indicators based on data availability in low and middle income countries. We conclude that public data are relatively well available for food system drivers and outcomes, but not for all of the food system activities. With only minor additional investments, existing surveys could be extended to cover a large part of the required additional data. For some indicators, however, targeted data collection efforts are needed. As the list of indicators partly overlaps with the indicators for the Sustainable Development Goals (SGDs), part of the collected data could serve not only to describe and monitor food systems, but also to track progress towards attaining the SDGs

Adipose Tissue, Bile Acids, and Gut Microbiome Species Associated With Gallstones After Bariatric Surgery

Several risk factors are associated with gallstone disease after bariatric surgery, but the underlying pathophysiological mechanisms of gallstone formation are unclear. We hypothesize that gallstone formation after bariatric surgery is induced by different pathways compared with gallstone formation in the general population, since postoperative formation occurs rapidly in patients who did not develop gallstones in preceding years. To identify both pathophysiological and potentially protective mechanisms against postoperative gallstone formation, we compared the preoperative fasting metabolome, fecal microbiome, and liver and adipose tissue transcriptome obtained before or during bariatric surgery of obese patients with and without postoperative gallstones. In total, 88 patients were selected from the BARIA longitudinal cohort study. Within this group, 32 patients had postoperative gallstones within 2 years. Gut microbiota metagenomic analyses showed group differences in abundance of 41 bacterial species, particularly abundance of Lactobacillaceae and Enterobacteriaceae in patients without gallstones. Subcutaneous adipose tissue transcriptomic analyses revealed four genes that were suppressed in gallstone patients compared with patients without gallstones. These baseline gene expression and gut microbiota composition differences might relate to protective mechanisms against gallstone formation after bariatric surgery. Moreover, baseline fasting blood samples of patients with postoperative gallstones showed increased levels of several bile acids. Overall, we revealed different genes and bacteria associated with gallstones than those previously reported in the general population, supporting the hypothesis that gallstone formation after bariatric surgery follows a different trajectory. Further research is necessary to confirm the involvement of the bile acids, adipose tissue activity, and microbial species observed here

Prospects and Bottlenecks of Reciprocal Partnerships Between the Private and Humanitarian Sectors in Cash Transfer Programming for Humanitarian Response

As an alternative to commodity-based programming (in-kind aid), Cash Transfer Programming is attracting both humanitarian organizations' and institutional donors' attention. Unlike in-kind aid, Cash Transfer Programming transfers purchasing power directly to beneficiaries in the form of currency or vouchers for them to obtain goods and/or services directly from the local market. In distributing currency to beneficiaries, the private sector, especially financial service providers, plays a prominent role, due to the humanitarian sector's limited relevant resources. The present work unveils challenges for the private and humanitarian sectors, which hinder implementing Cash Transfer Programming. Based on primary and secondary qualitative data, the paper presents the main characteristics and the mechanisms of Cash Transfer Programming to explore how the private sector is involved with Cash Transfer Programming. Then, this study presents bottlenecks of reciprocal relationships between financial service providers and humanitarian organizations in Cash Transfer Programming

Type 2 diabetes is associated with increased circulating levels of 3-hydroxydecanoate activating GPR84 and neutrophil migration

Obesity and diabetes are associated with inflammation and altered plasma levels of several metabolites, which may be involved in disease progression. Some metabolites can activate G protein-coupled receptors (GPCRs) expressed on immune cells where they can modulate metabolic inflammation. Here, we find that 3-hydroxydecanoate is enriched in the circulation of obese individuals with type 2 diabetes (T2D) compared with nondiabetic controls. Administration of 3-hydroxydecanoate to mice promotes immune cell recruitment to adipose tissue, which was associated with adipose inflammation and increased fasting insulin levels. Furthermore, we demonstrate that 3-hydroxydecanoate stimulates migration of primary human and mouse neutrophils, but not monocytes, through GPR84 and Gαi signaling in vitro. Our findings indicate that 3-hydroxydecanoate is a T2D-associated metabolite that increases inflammatory responses and may contribute to the chronic inflammation observed in diabetes

A systems biology approach to understand gut microbiota and host metabolism in morbid obesity: design of the BARIA Longitudinal Cohort Study

Introduction: Prevalence of obesity and associated diseases, including type 2 diabetes mellitus, dyslipidaemia and non-alcoholic fatty liver disease (NAFLD), are increasing. Underlying mechanisms, especially in humans, are unclear. Bariatric surgery provides the unique opportunity to obtain biopsies and portal vein blood-samples. Methods: The BARIA Study aims to assess how microbiota and their metabolites affect transcription in key tissues and clinical outcome in obese subjects and how baseline anthropometric and metabolic characteristics determine weight loss and glucose homeostasis after bariatric surgery. We phenotype patients undergoing bariatric surgery (predominantly laparoscopic Roux-en-Y gastric bypass), before weight loss, with biometrics, dietary and psychological questionnaires, mixed meal test (MMT) and collect fecal-samples and intra-operative biopsies from liver, adipose tissues and jejunum. We aim to include 1500 patients. A subset (approximately 25%) will undergo intra-operative portal vein blood-sampling. Fecal-samples are analyzed with shotgun metagenomics and targeted metabolomics, fasted and postprandial plasma-samples are subjected to metabolomics, and RNA is extracted from the tissues for RNAseq-analyses. Data will be integrated using state-of-the-art neuronal networks and metabolic modeling. Patient follow-up will be ten years. Results: Preoperative MMT of 170 patients were analysed and clear differences were observed in glucose homeostasis between individuals. Repeated MMT in 10 patients showed satisfactory intra-individual reproducibility, with differences in plasma glucose, insulin and triglycerides within 20% of the mean difference. Conclusion: The BARIA study can add more understanding in how gut-microbiota affect metabolism, especially with regard to obesity, glucose metabolism and NAFLD. Identification of key factors may provide diagnostic and therapeutic leads to control the obesity-associated disease epidemic

Reverse thinking: taking a healthy diet perspective towards food systems transformations

Food systems that deliver healthy diets without exceeding the planet’s resources are essential to achieve the worlds’ ambitious development goals. Healthy diets need to be safe, accessible, and affordable for all, including for disadvantaged and nutritionally vulnerable groups such as of smallholder producers, traders, and consumers in low- and middle-income countries. Globally, food systems are experiencing rapid and drastic changes and are failing to fulfil these multiple duties simultaneously. The international community therefore calls for rigorous food systems transformations and policy solutions to support the achievement of healthy diets for all. Most strategies, however, are essentially supply- and market-oriented. Incorporation of a healthy diet perspective in food system transformation is essential to enable food systems to deliver not only on supplying nutritious foods but also on ensuring that consumers have access can afford and desire healthy, sustainable, and culturally acceptable diets. This paper argues that this should be guided by information on diets, dietary trends, consumer motives, and food environment characteristics. Transformational approaches and policies should also take into account the stage of food system development requiring different strategies to ensure healthier diets for consumers. We review current knowledge on drivers of consumer choices at the individual and food environment level with special emphasis on low- and middle income countries, discuss the converging and conflicting objectives that exist among multiple food-system actors, and argue that failure to strengthen synergies and resolve trade-offs may lead to missed opportunities and benefits, or negative unintended consequences in food system outcomes. The paper proposes a menu of promising consumer- and food-environment- oriented policy options to include in the food systems transformation agenda in order to shift LMIC consumer demand towards healthier diets in low- and middle income countries

Gut-derived bacterial flagellin induces beta-cell inflammation and dysfunction

Hyperglycemia and type 2 diabetes (T2D) are caused by failure of pancreatic beta cells. The role of the gut microbiota in T2D has been studied, but causal links remain enigmatic. Obese individuals with or without T2D were included from two independent Dutch cohorts. Human data were translated in vitro and in vivo by using pancreatic islets from C57BL6/J mice and by injecting flagellin into obese mice. Flagellin is part of the bacterial locomotor appendage flagellum, present in gut bacteria including Enterobacteriaceae, which we show to be more abundant in the gut of individuals with T2D. Subsequently, flagellin induces a pro-inflammatory response in pancreatic islets mediated by the Toll-like receptor (TLR)-5 expressed on resident islet macrophages. This inflammatory response is associated with beta-cell dysfunction, characterized by reduced insulin gene expression, impaired proinsulin processing and stress-induced insulin hypersecretion in vitro and in vivo in mice. We postulate that increased systemically disseminated flagellin in T2D is a contributing factor to beta-cell failure in time and represents a novel therapeutic target.Peer reviewe