This review will describe the evidence for changing the hospital environment to improve nutrition of older people, with particular emphasis on the role of additional mealtime assistance. Poor nutrition among older people in hospital is well recognised in many countries and is associated with poor outcomes of hospital care including increased mortality and longer lengths of stay. Factors recognised to contribute to poor dietary intake include acute illness, co-morbidities, cognitive impairment, low mood and medication. The hospital environment has also been scrutinised with reports from many countries of food being placed out of reach or going cold because time-pressured ward and catering staff often struggle to help an increasingly dependent group of patients at mealtimes. Routine screening in hospital for people at risk of under nutrition is recommended. Coloured trays and protected mealtimes are widespread although there is relatively little evidence for their impact on dietary intake. Volunteers can be trained to sfely give additional mealtime assistance including feeding to older patients on acute medical wards. They can improve the quality of mealtime care for patients and nursing staff although the evidence for improved dietary intake is mixed. In conclusion, improving the nutrition of older patients in hospital is challenging. Initiatives such as routine screening, the use of coloured trays, protected mealtimes and additional mealtime assistance can work together synergistically. Volunteers are likely to be increasingly important in an era when healthcare systems are generally limited in both financial resources and the ability to recruit sufficient nursing staff.

The theme of The Nutrition Society Spring Conference 2017 was on the interaction between nutrition and exercise for promoting healthy ageing, maintaining cognitive function and improving the metabolic health of the population. The importance of this theme is highlighted by the public health issues surrounding obesity, diabetes and the age-related loss of skeletal muscle mass (sarcopenia). The opening symposium provided a historical perspective of both invasive and non-invasive methodologies for measuring exercise energetics and energy balance. Data derived from these techniques underpin current understanding regarding the metabolic response to nutrition and exercise. Further symposia examined the importance of skeletal muscle for healthy ageing in older men and postmenopausal women. From a nutritional perspective, the potential for animal- v. plant-based protein sources to offset the age-related decline in muscle mass was discussed. The day concluded by discussing the link(s) between nutrition, exercise and brain function. Day 2 commenced with examples of applied equine research illustrating the link between nutrition/exercise and insulin resistance to those of a human model. The final symposium examined the combined role of nutrition and exercise in reducing risk of type 2 diabetes and dyslipidaemia. The overall conclusion from the meeting was that the interaction between diet and physical activity confers greater benefits to human health and performance than either component alone.

The urban environment has changed vastly over past decades, which also has had an impact on our sleep and dietary patterns and possibly health outcomes. Some studies have shown that sleep duration and sleep quality has declined over past decades, especially in children. In parallel, our lifestyle and dietary patterns have also changed including more shift work, more meals outside the home or family setting and more irregular eating patterns, including breakfast skipping and late-night eating. This new area of research in nutritional sciences studying the impact of the timing of eating on health outcomes is called chrono-nutrition, and combines elements from nutritional research with chrono-biology. The objectives of this paper were to discuss secular trends in sleep patterns and related dietary patterns, introduce basic concepts and mechanisms of chrono-nutrition and discuss the evidence for the importance of sleep and chrono-nutrition in relation to health outcomes. Overall, chrono-nutrition could mediate the effects between sleep, diet and urbanisation, and more research is needed to elucidate the importance of chrono-nutrition for metabolic health and its impact on public health.

Radiotherapy-induced damage to non-cancerous gastrointestinal mucosa has effects on secretory and absorptive functions and can interfere with normal gastrointestinal physiology. Nutrient absorption and digestion may be compromised. Dietary manipulation is an attractive option with sound rationale for intervention. The aim of this review was to synthesise published evidence for the use of elemental formulae, low or modified fat diets, fibre, lactose restriction and probiotics, prebiotics and synbiotics to protect the bowel from gastrointestinal side effects during long-course, radical pelvic radiotherapy. Thirty original studies (recruiting n 3197 patients) were identified comprising twenty-four randomised controlled trials, four cohort studies and two comparator trials. Endpoints varied and included symptom scales (Inflammatory Bowel Disease Questionnaire, Common Technology Criteria for Adverse Events, Radiation Therapy Oncology Group) and Bristol Stool Scale. Dietary and supplement interventions were employed with many studies using a combination of interventions. Evidence from RCT was weak for elemental, low or modified fat and low-lactose interventions and modestly positive for the manipulation of fibre during radiotherapy. Evidence for probiotics as prophylactic interventional agents was more promising with a number of trials reporting positive results but strength and strains of interventions vary, as do methodologies and endpoints making it difficult to arrive at firm conclusions with several studies lacking statistical power. This consolidated review concludes that there is insufficient high-grade evidence to recommend nutritional intervention during pelvic radiotherapy. Total replacement of diet with elemental formula could be effective in severe toxicity but this is unproven. Probiotics offer promise but cannot be introduced into clinical practice without rigorous safety analysis, not least in immunocompromised patients.

The circadian disruption in shift-workers is suggested to be a risk factor to develop overweight and metabolic dysfunction. The conflicting time signals given by shifted activity, shifted food intake and exposure to light at night occurring in the shift-worker are proposed to be the cause for the loss of internal synchrony and the consequent adverse effects on body weight and metabolism. Because food elicited signals have proven to be potent entraining signals for peripheral oscillations, here we review the findings from experimental models of shift-work and verify whether they provide evidence about the causal association between shifted feeding schedules, circadian disruption and altered metabolism. We found mainly four experimental models that mimic the conditions of shift-work: protocols of forced sleep deprivation, of forced activity during the normal rest phase, exposure to light at night and shifted food timing. A big variability in the intensity and duration of the protocols was observed, which led to a diversity of effects. A common result was the disruption of temporal patterns of activity; however, not all studies explored the temporal patterns of food intake. According to studies that evaluate time of food intake as an experimental model of shift-work and studies that evaluate shifted food consumption, time of food intake may be a determining factor for the loss of balance at the circadian and metabolic level.

High BMI is associated with an increased risk of breast cancer in post-menopausal women but poorer outcomes in all age groups. The underlying mechanism is likely to be multi-factorial. Patients with a high BMI may present later due to body habitus. Some studies have also indicated an increased incidence of biologically adverse features, including a higher frequency of oestrogen receptor (ER negative) tumours, in obese patients. Obese patients have a higher frequency of surgical complications, potentially delaying systemic therapies, and reports suggest that chemotherapy and endocrine therapy are less effective in patients with BMI ≥30 kg/m2.

High BMI is generally interpreted as excess adiposity and a World Cancer Research Fund report judged that the associations between BMI and incidence of breast cancer were due to body fatness. However, BMI cannot distinguish lean mass from fat mass, or characterise body fat distribution. Most chemotherapy drugs are dosed according to calculated body surface area (BSA). Patients with a similar BSA or BMI may have wide variations in their distribution of adipose tissue and skeletal muscle (body composition); however, few studies have looked at the effect of this on chemotherapy tolerance or effectiveness. Finally, adjuvant treatments for breast cancer can themselves result in body composition changes.

Research is required to fully understand the biological mechanisms by which obesity influences cancer behaviour and the impact of obesity on treatment effectiveness and tolerance so that specific management strategies can be developed to improve the prognosis of this patient group.

The use of taxes to promote healthy nutritional behaviour has gained ground in the past decade. The present paper reviews existing applications of fiscal instruments in nutrition policy and derives some perspectives and recommendations from the experiences gained with these instruments. Many countries in different parts of the world have experiences with the taxation of sugar-sweetened beverages, in some cases in combination with taxes on unhealthy food commodities such as confectionery or high-fat foods. These tax schemes have many similarities, but also differ in their definitions of tax objects and in the applied tax rates. Denmark has been the only country in the world to operate a tax on saturated fat content in foods, from 2011 to 2012. Most of the existing food tax schemes have been introduced from fiscal motivations, with health promotion as a secondary objective, but a few have been introduced with health promotion as the primary objective. The diversity in experiences from existing tax schemes can provide valuable insights for future use of fiscal instruments to promote healthy nutrition, in terms of designing effective and efficient tax or subsidy instruments, and in terms of smooth and politically viable implementation of the instruments.

The doubly labelled water method for the measurement of total daily energy expenditure (TDEE) over 1–3 weeks under daily living conditions is the indicated method to study effects of exercise and extreme environments on energy balance. Subjects consume a measured amount of doubly labelled water (2H218O) to increase background enrichment of body water for 18O and 2H, and the subsequent difference in elimination rate between 18O and 2H, as measured in urine, saliva or blood samples, is a measure for carbon dioxide production and thus allows calculation of TDEE. The present review describes research showing that physical activity level (PAL), calculated as TDEE (assessed with doubly labelled water) divided by resting energy expenditure (REE, PAL = TDEE/REE), reaches a maximum value of 2·00–2·40 in subjects with a vigorously active lifestyle. Higher PAL values, while maintaining energy balance, are observed in professional athletes consuming additional energy dense foods to compete at top level. Exercise training can increase TDEE/REE in young adults to a value of 2·00–2·40, when energy intake is unrestricted. Furthermore, the review shows an exercise induced increase in activity energy expenditure can be compensated by a reduction in REE and by a reduction in non-exercise physical activity, especially at a negative energy balance. Additionally, in untrained subjects, an exercise-induced increase in activity energy expenditure is compensated by a training-induced increase in exercise efficiency.

Poor diets are a significant contributor to non-communicable diseases and obesity. Despite years of health promotion, change in dietary habits is slow and there is growing recognition of the need to provide greater support to individuals and to complement individual efforts with changes in the food environment to shift the default towards healthier diets. The present paper summarises opportunities for intervention at the individual and population level. It discusses the role of voluntary or mandatory approaches to drive change in the food industry and the need for improved methods to monitor and evaluate progress. It concludes with a call to action from all stakeholders to accelerate change towards a healthier diet.

Fat and carbohydrate are the major fuel sources utilised for oxidative, mitochondrial ATP resynthesis during human skeletal muscle contraction. The relative contribution of these two substrates to ATP resynthesis and total energy expenditure during exercise can vary substantially, and is predominantly determined by fuel availability and exercise intensity and duration. For example, the increased ATP demand that occurs with an increase in exercise intensity is met by increases in both fat and carbohydrate oxidation up to an intensity of approximately 60–70 % of maximal oxygen consumption. When exercise intensity increases beyond this workload, skeletal muscle carbohydrate utilisation is accelerated, which results in a reduction and inhibition of the relative and absolute contribution of fat oxidation to total energy expenditure. However, the precise mechanisms regulating muscle fuel selection and underpinning the decline in fat oxidation remain unclear. This brief review will primarily address the theory that a carbohydrate flux-mediated reduction in the availability of muscle carnitine to the mitochondrial enzyme carnitine palmitoyltransferase 1, a rate-limiting step in mitochondrial fat translocation, is a key mechanism for the decline in fat oxidation during high-intensity exercise. This is discussed in relation to recent work in this area investigating fuel metabolism at various exercise intensities and taking advantage of the discovery that skeletal muscle carnitine content can be nutritionally increased in vivo in human subjects.