Low-carbohydrate diets (LCD) have been promoted for weight control and type 2 diabetes (T2D) management, based on an emerging body of evidence, including meta-analyses with an indication of publication bias. Proposed definitions vary between 50 and 130 g/d, or <10 and <40 % of energy from carbohydrate, with no consensus on LCD compositional criteria. LCD are usually followed with limited consideration for other macronutrients in the overall diet composition, introducing variance in the constituent foods and in metabolic responses. For weight management, extensive evidence supports LCD as a valid weight loss treatment, up to 1–2 years. Solely lowering carbohydrate intake does not, in the medium/long term, reduce HbA1c for T2D prevention or treatment, as many mechanisms interplay. Under controlled feeding conditions, LCD are not physiologically or clinically superior to diets with higher carbohydrates for weight-loss, fat loss, energy expenditure or glycaemic outcomes; indeed, all metabolic improvements require weight loss. Long-term evidence also links the LCD pattern to increased CVD risks and mortality. LCD can lead to micronutrient deficiencies and increased LDL-cholesterol, depending on food selection to replace carbohydrates. Evidence is limited but promising regarding food choices/sources to replace high-carbohydrate foods that may alleviate the negative effects of LCD, demanding further insight into the dietary practice of medium to long term LCD followers. Long-term, high-quality studies of LCD with different food sources (animal and/or plant origins) are needed, aiming for clinical endpoints (T2D incidence and remission, cardiovascular events, mortality). Ensuring micronutrient adequacy by food selection or supplementation should be considered for people who wish to pursue long-term LCD.

The present paper reviews the evidence as to whether patients on lipid-lowering drugs should restrict dietary SFA intake. Premature mortality from atherosclerotic CVD has fallen dramatically in many high-income countries. This appears to be due to a combination of improved treatment following a cardiovascular event and reduced risk factors, including LDL-cholesterol. Whether this reduction is due to changes in dietary habits, or the increasing availability of highly potent cholesterol-reducing drugs remains to be firmly established. While reducing dietary SFA intake has been the cornerstone of public health nutrition policy for several decades, the efficacy of such dietary changes has been challenged in recent years. While there remains a lack of consensus in the literature, there is an emerging view that dietary advice should be specifically modified to emphasise replacing SFA with PUFA in the diet rather than carbohydrate. The advice to moderate dietary SFA intake given to the general population is usually also given to those individuals at high risk of CVD who are prescribed lipid-lowering drugs. There is limited evidence to suggest that any potential benefit of such a diet on LDL-cholesterol may be offset by a concurrent decrease in HDL-cholesterol. However, as diets rich in SFA are frequently energy-dense, and rich in red and processed meat (potential risk factors for CVD in themselves), it would seem prudent to continue to advise patients on lipid-lowering drugs to maintain a low-fat diet.

Elderly patients are at risk of malnutrition and need an appropriate assessment of energy requirements. In the clinical setting, predictive equations are widely used to estimate the Resting Energy Expenditure (REE). Although easy to use, these equations are not always validated in the elderly and, even if validated, they often provide different outputs of energy requirements for the same subject. The aim of the present work is to develop a web-based application helping clinicians in finding out the most appropriate equation for estimating the REE for each subject. The web-based application is based on a systematic review of the equations for the estimation of REE in the elderly. The systematic review was carried out on PubMed and Scopus following the PRISMA guidelines. Studies in subjects older than 65 years of age that tested the performance of a predictive equation for the estimation of REE vs. a gold standard (indirect calorimetry or doubly labeled water) were included in the review. Studies performed in critically ill elderly patients were excluded. The initial search identified 2035 studies. The final review included 50 studies. Included studies were mainly observational, conducted in healthy elderly subjects enrolled in the outpatient setting, and using indirect calorimetry as the gold standard. The 50 studies included in the review corresponded to 189 different equations. Several parameters were included in the equations, and they can be divided as following: anthropometric characteristics, body composition parameters, environmental measures, laboratory tests, the presence of comorbidities, and physical activity frequency. The equations retrieved were tested on a sample of 88 subjects aged > 65 years enrolled in an Italian nursing home. Based on the systematic review and the pilot testing of the equations, it has been developed a web application (http://r-ubesp.dctv.unipd.it:3838/equationer) that allows for the estimation of REE using the equation most appropriate according to the subject's characteristic and parameters available. The assessment of the energy requirements in the elderly is crucial for the management of nutritional problems in this population group since nutritional problems are related to worse health outcomes. The present study showed a wide use of different type of equations for the estimation of REE in the elderly highlighting the need of choosing the most appropriate predictive equation according to the subject characteristics and health status. The web application will help clinicians in doing that.

Epidemiological and clinical evidence highlight the benefit of dietary fibre consumption on body weight. This benefit is partly attributed to the interaction of dietary fibre with the gut microbiota. Dietary fibre possesses a complex food structure which resists digestion in the upper gut and therefore reaches the distal gut where it becomes available for bacterial fermentation. This process yields SCFA which stimulate the release of appetite-suppressing hormones glucagon-like peptide-1 and peptide YY. Food structures can further enhance the delivery of fermentable substrates to the distal gut by protecting the intracellular nutrients during upper gastrointestinal digestion. Domestic and industrial processing can disturb these food structures that act like barriers towards digestive enzymes. This leads to more digestible products that are better absorbed in the upper gut. As a result, less resistant material (fibre) and intracellular nutrients may reach the distal gut, thus reducing substrates for bacterial fermentation and its subsequent benefits on the host metabolism including appetite suppression. Understanding this link is essential for the design of diets and food products that can promote appetite suppression and act as a successful strategy towards obesity management. This article reviews the current evidence in the interplay between food structure, bacterial fermentation and appetite control.

CVD is a major burden on the health system in the UK. On average, diets are not aligned with current dietary recommendations, including those for salt, saturated fat, fibre, fruit and vegetables. Obesity prevalence is high and the majority of the population is consuming more energy than required. Addressing these issues would reduce the burden of CVD and help reduce inequalities in health. There is currently a range of policy interventions in place in England designed to help improve diets and reduce obesity, which in turn should help reduce the risk of CVD. Further actions may be needed in the long term to deliver sustained improvements to diet and health.

A Nutrition Society member-led meeting was held on 9 January 2020 at The University of Surrey, UK. Sixty people registered for the event, and all were invited to participate, either through chairing a session, presenting a ‘3 min lightning talk’ or by presenting a poster. The meeting consisted of an introduction to the topic by Dr Barbara Fielding, with presentations from eight invited speakers. There were also eight lightning talks and a poster session. The meeting aimed to highlight recent research that has used stable isotope tracer techniques to understand human metabolism. Such studies have irrefutably shaped our current understanding of metabolism and yet remain a mystery to many. The meeting aimed to de-mystify their use in nutrition research.

The WHO encourages countries to conduct national dietary surveys (NDS) to inform preventative policies targeting malnutrition and noncommunicable diseases. Previous reviews have found inadequate nutrient intakes and survey provision across Europe. This research is the first to provide an updated review of NDS provision within the whole WHO European Region, across the lifecourse, with reference to disadvantaged groups, obesity and nutrients of concern. Over a third of WHO European countries, mainly Central and Eastern European countries (CEEC), had no identifiable NDS. Where countries reported nutrient intakes, poor WHO recommended nutrient intake attainment was Europe-wide across the lifecourse, particularly in CEEC. Lower educated individuals had poorer diet quality. However, heterogeneity in age group sampled, dietary assessment method, nutrient composition database and under-reporting hindered inter-country comparisons. Average population trans fatty acid intakes below WHO recommended limits may hide inequalities in disadvantaged groups; legislative bans may help alleviate this. There were few associations between NDS-derived consumed food portion size (FPS) and BMI. However, consumed FPS was greater than on-pack serving-size in the majority of foods studied. This review illustrates how NDS can generate information on diet, nutrient intakes and the food environment. However, to enable valid inter-country comparisons, countries should be encouraged to conduct and report harmonised NDS, particularly in the age groups sampled, dietary assessment methodology, nutrient range, underpinning food composition database and treatment of under-reporters. This will aid effective, coordinated policy development that can have a real impact on dietary improvement, on a population and subgroup level, throughout Europe.

The concept of food addiction is currently a highly debated subject within both the general public and the scientific communities. The term food addiction suggests that individuals may experience addictive-like responses to food, similar to those seen with classic substances of abuse. An increasing number of studies have established the prevalence and correlates of food addiction. Moreover, food addiction may be associated with obesity and disordered eating. Thus, intervening on food addiction may be helpful in the prevention and therapy of obesity and eating disorders. However, controversy exists about if this phenomenon is best defined through paradigms reflective of Diagnostic and Statistical Manual of Mental Disorders (DSM-5) substance-related disorders (e.g. food addiction) or non-substance-related disorders (e.g. eating addiction) criteria. This review paper will give a brief summarisation of the current state of research on food addiction, a more precise definition of its classification, its differentiation from eating addiction and an overview on potential overlaps with eating disorders. Based on this review, there is evidence that food addiction may represent a distinct phenomenon from established eating disorders such as bulimia nervosa or binge-eating disorder. Future studies are needed to further examine and establish orthogonal diagnostic criteria specific to food addiction. Such criteria must differentiate the patterns of eating and symptoms that may be similar to those of eating disorders to further characterise food addiction and develop therapy options. To date, it is too premature to draw conclusions about the clinical significance of the concept of food addiction.

The global prevalence of obesity and obesity-associated cardiometabolic diseases is a significant public health burden. Chronic low-grade inflammation in metabolic tissues such as white adipose tissue (WAT) is linked to obesity and may play a role in disease progression. The overconsumption of dietary fat has been suggested to modulate the WAT inflammatory environment. It is also recognised that fats varying in degree of fatty acid saturation may elicit differential WAT inflammatory responses. This information has originated predominantly from animal or cell models and translation into human participants in vivo remains limited. This review will summarise human intervention studies investigating the effect of dietary fat quantity and quality on subcutaneous WAT inflammation, with a specific focus on the toll-like receptor 4 (TLR4)/NF-κB and nucleotide-binding and oligomerisation domain-like receptor, leucine-rich repeat and pyrin domain-containing 3 (NLRP3) inflammasome molecular signalling pathways. Overall, firm conclusions are hard to draw regarding the effect of dietary fat quantity and quality on WAT inflammatory responses due to the heterogeneity of study designs, diet composition and participant cohorts recruited. Previous studies have predominantly focused on measures of WAT gene expression. It is suggested that future work includes measures of WAT total content and phosphorylation of proteins involved in TLR4/NF-κB and NLRP3 signalling as this is more representative of alterations in WAT physiological function. Understanding pathways linking the intake of total fat and specific fatty acids with WAT metabolic-inflammatory responses may have important implications for public health by informing dietary guidelines aimed at cardiometabolic risk reduction.