Predicting the profile of nutrients available for absorption: from nutrient requirement to animal response and environmental impact

Current feed evaluation systems for dairy cattle aim to match nutrient requirements with nutrient intake at pre-defined production levels. These systems were not developed to address, and are not suitable to predict, the responses to dietary changes in terms of production level and product composition, excretion of nutrients to the environment, and nutrition related disorders. The change from a requirement to a response system to meet the needs of various stakeholders requires prediction of the profile of absorbed nutrients and its subsequent utilisation for various purposes. This contribution examines the challenges to predicting the profile of nutrients available for absorption in dairy cattle and provides guidelines for further improved prediction with regard to animal production responses and environmental pollution. The profile of nutrients available for absorption comprises volatile fatty acids, long-chain fatty acids, amino acids and glucose. Thus the importance of processes in the reticulo-rumen is obvious. Much research into rumen fermentation is aimed at determination of substrate degradation rates. Quantitative knowledge on rates of passage of nutrients out of the rumen is rather limited compared with that on degradation rates, and thus should be an important theme in future research. Current systems largely ignore microbial metabolic variation, and extant mechanistic models of rumen fermentation give only limited attention to explicit representation of microbial metabolic activity. Recent molecular techniques indicate that knowledge on the presence and activity of various microbial species is far from complete. Such techniques may give a wealth of information, but to include such findings in systems predicting the nutrient profile requires close collaboration between molecular scientists and mathematical modellers on interpreting and evaluating quantitative data. Protozoal metabolism is of particular interest here given the paucity of quantitative data. Empirical models lack the biological basis necessary to evaluate mitigation strategies to reduce excretion of waste, including nitrogen, phosphorus and methane. Such models may have little predictive value when comparing various feeding strategies. Examples include the Intergovernmental Panel on Climate Change (IPCC) Tier II models to quantify methane emissions and current protein evaluation systems to evaluate low protein diets to reduce nitrogen losses to the environment. Nutrient based mechanistic models can address such issues. Since environmental issues generally attract more funding from governmental offices, further development of nutrient based models may well take place within an environmental framework.

Foods derived from animals: the impact of animal nutrition on their nutritive value and ability to sustain long-term health

Foods derived from domestic animals are a significant source of nutrients in the UK diet. However, certain aspects of some animal-derived foods, notably levels of saturated fatty acids, have given rise to concerns that these foods may contribute to the risk of cardiovascular disease, the metabolic syndrome and other conditions. However, the composition of the many animal-derived foods is not constant and can often be enhanced by manipulating the nutrition of the animal. This paper reviews these possibilities with particular attention to lipids, and draws attention to the fact that milk in particular, contains a number of compounds which may, for example, exert anti-carcinogenic effects. It is clear that the role of animal nutrition in creating foods closer to the optimum composition for long-term human health will not only be more relevant in the future, but will be vital in attempts to improve the health of the human population.

Probiotics: their potential to impact human health

Probiotics—live microorganisms that when administered in adequate amounts confer a health benefit on the host—have been studied for both human and animal applications, and worldwide research on this topic has accelerated in recent years. This paper reviews the literature on probiotics, describes how probiotics work in human ecosystems, and outlines the impact of probiotics on human health and disease. The paper also addresses safety issues of probiotic use, suggests future developments in the field of probiotics, and provides research and policy recommendations. Product considerations and potential future developments regarding probiotics also are discussed. The authors conclude that controlled human studies have revealed a diverse range of health benefits from consumption of probiotics, due largely to their impact on immune function or on microbes colonizing the body. Additional, well-designed and properly controlled human and mechanistic studies with probiotics will advance the essential understanding of active principles, mechanisms of action, and degree of effects that can be realized by specific consumer groups. Recommendations include establishment of a standard of identity for the term “probiotic,” adoption of third-party verification of label claims, use of probiotics selectively in clinical conditions, and use of science-based assessment of the benefits and risks of genetically engineered probiotic microbes.

Hospital catering systems and their impact on the sensorial profile of foods provided to older patients in the UK

Impaired sensorial perception is very common in older people and low sensorial quality of foods is associated with decreased appetite and dietary intake. Hospital undernutrition in older patients could be linked to sensorial quality of hospital food if the quality were low or inappropriate for older people. The aim of this study was to examine changes in the sensorial quality of different foods that occur as a result of the food journey (i.e. freezing, regeneration, etc.) in the most common hospital catering systems in the UK. A trained sensory panel assessed sensorial descriptors of certain foods with and without the hospital food journey as it occurs in the in-house and cook/freeze systems. The results showed effects of the food journey on a small number of sensorial descriptors related to flavour, appearance and mouthfeel. The majority of these effects were due to temperature changes, which caused accumulation of condensation. A daily variation in sensorial descriptors was also detected and in some cases it was greater than the effect of the food journey. This study has shown that changes occur in the sensory quality of meals due to hospital food journeys, however these changes were small and are not expected to substantially contribute to acceptability or have a major role in hospital malnutrition.

Impact of the quantity and flavonoid content of fruits and vegetables on markers of intake in adults with an increased risk of cardiovascular disease: the FLAVURS Trial

Purpose Limited robust randomised controlled trials investigating fruit and vegetable (F&V) intake in people at risk of cardiovascular disease (CVD) exist. We aimed to design and validate a dietary strategy of increasing flavonoid-rich versus flavonoid-poor F&V consumption on nutrient biomarker profile. Methods A parallel, randomised, controlled, dose–response dietary intervention study. Participants with a CVD relative risk of 1.5 assessed by risk scores were randomly assigned to one of the 3 groups: habitual (control, CT), high-flavonoid (HF) or low-flavonoid (LF) diets. While the CT group (n = 57) consumed their habitual diet throughout, the HF (n = 58) and LF (n = 59) groups sequentially increased their daily F&V intake by an additional 2, 4 and 6 portions for 6-week periods during the 18-week study. Results Compliance to target numbers and types of F&V was broadly met and verified by dietary records, and plasma and urinary biomarkers. Mean (±SEM) number of F&V portions/day consumed by the HF and LF groups at baseline (3.8 ± 0.3 and 3.4 ± 0.3), 6 weeks (6.3 ± 0.4 and 5.8 ± 0.3), 12 weeks (7.0 ± 0.3 and 6.8 ± 0.3) and 18 weeks (7.6 ± 0.4 and 8.1 ± 0.4), respectively, was similar at baseline yet higher than the CT group (3.9 ± 0.3, 4.3 ± 0.3, 4.6 ± 0.4, 4.5 ± 0.3) (P = 0.015). There was a dose-dependent increase in dietary and urinary flavonoids in the HF group, with no change in other groups (P = 0.0001). Significantly higher dietary intakes of folate (P = 0.035), non-starch polysaccharides (P = 0.001), vitamin C (P = 0.0001) and carotenoids (P = 0.0001) were observed in both intervention groups compared with CT, which were broadly supported by nutrient biomarker analysis. Conclusions The success of improving nutrient profile by active encouragement of F&V intake in an intervention study implies the need for a more hands-on public health approach.

Children of the golden minster: St. Oswald's Priory and the impact of industrialisation on child health.

This study explores the disease experience of children buried within the cemetery of St. Oswald’s Priory, Gloucester from AD1153 to 1857. Evidence for ages-at-death, infant mortality, and the prevalence of stress indicators, trauma, and pathology were compared between the early and postmedieval periods. The skeletal remains of these children provide evidence for child health spanning the economic expansion of Gloucester at St. Oswald’s, from a mostly rural parish to a graveyard catering for families from the poorer northern part of the town and the workhouse. Results showed that the children from the postmedieval period in Gloucester suffered higher rates of dental caries (38%) and congenital conditions (17.3%) than their counterparts from the early and later medieval period. This paper serves to highlight the value of nonadult skeletal material in the interpretation of past human health in transitional societies and illustrates the wide variety of pathological conditions that can be observed in nonadult skeletons.

Dairy and cardiovascular health: friend or foe?

Cardiovascular disease (CVD) prevalence at a global level is predicted to increase substantially over the next decade due to the increasing ageing population and incidence of obesity. Hence, there is an urgent requirement to focus on modifiable contributors to CVD risk, including a high dietary intake of saturated fatty acids (SFA). As an important source of SFA in the UK diet, milk and dairy products are often targeted for SFA reduction. The current paper acknowledges that milk is a complex food and that simply focusing on the link between SFA and CVD risk overlooks the other beneficial nutrients of dairy foods. The body of existing prospective evidence exploring the impact of milk and dairy consumption on risk factors for CVD is reviewed. The current paper highlights that high milk consumption may be beneficial to cardiovascular health, while illustrating that the evidence is less clear for cheese and butter intake. The option of manipulating the fatty acid profile of ruminant milk is discussed as a potential dietary strategy for lowering SFA intake at a population level. The review highlights that there is a necessity to perform more well-controlled human intervention-based research that provides a more holistic evaluation of fat-reduced and fat-modified dairy consumption on CVD risk factors including vascular function, arterial stiffness, postprandial lipaemia and markers of inflammation. Additionally, further research is required to investigate the impact of different dairy products and the effect of the specific food matrix on CVD development.

Impact of postprandial glycaemia on health and prevention of disease

Postprandial glucose, together with related hyperinsulinemia and lipidaemia, has been implicated in the development of chronic metabolic diseases like obesity, type 2 diabetes mellitus (T2DM) and cardiovascular disease (CVD). In this review, available evidence is discussed on postprandial glucose in relation to body weight control, the development of oxidative stress, T2DM, and CVD and in maintaining optimal exercise and cognitive performance. There is mechanistic evidence linking postprandial glycaemia or glycaemic variability to the development of these conditions or in the impairment in cognitive and exercise performance. Nevertheless, postprandial glycaemia is interrelated with many other (risk) factors as well as to fasting glucose. In many studies, meal-related glycaemic response is not sufficiently characterized, or the methodology with respect to the description of food or meal composition, or the duration of the measurement of postprandial glycaemia is limited. It is evident that more randomized controlled dietary intervention trials using effective low vs. high glucose response diets are necessary in order to draw more definite conclusions on the role of postprandial glycaemia in relation to health and disease. Also of importance is the evaluation of the potential role of the time course of postprandial glycaemia.

Comparison of in vivo and in vitro digestion on polyphenol composition in lingonberries: potential impact on colonic health

The composition of polyphenols in ileal fluid samples obtained from an ileostomy subject after lingonberry intake was compared with lingonberry extracts obtained after simulated in vitro digestion (IVDL) and subsequent faecal fermentation (IVFL). HPLC-PDA-MS/MS analysis confirmed similar patterns of lingonberry (poly)phenolic metabolism after the in vivo and in vitro digestion, with reduced recovery of anthocyanins and a similar pattern of recovery for proanthocyanidins observed for both methods of digestion. On the other hand, the IVFL sample contained none of the original (poly)phenolic components but was enriched in simple aromatic components. Digested and fermented extracts exhibited significant (P < 0.05) anti-genotoxic (Comet assay), anti-mutagenic (Mutation Frequency assay), and anti-invasive (Matrigel Invasion assay) effects in human cell culture models of colorectal cancer at physiologically-relevant doses (0-50 μg/mL gallic acid equivalents). The ileal fluid induced significant anti-genotoxic activity (P < 0.05), but at a higher concentration (200 μg/mL gallic acid equivalents) than the IVDL. Despite extensive structural modification following digestion and fermentation, lingonberry extracts retained their bioactivity in vitro. This reinforces the need for studies to consider the impact of digestion when investigating bioactivity of dietary phytochemicals.

The perceived impact of the National Health Service on personalised nutrition service delivery among the UK public

Personalised nutrition (PN) has the potential to reduce disease risk and optimise health and performance. Although previous research has shown good acceptance of the concept of PN in the UK, preferences regarding the delivery of a PN service (e.g. online v. face-to-face) are not fully understood. It is anticipated that the presence of a free at point of delivery healthcare system, the National Health Service (NHS), in the UK may have an impact on end-user preferences for deliverances. To determine this, supplementary analysis of qualitative data obtained from focus group discussions on PN service delivery, collected as part of the Food4Me project in the UK and Ireland, was undertaken. Irish data provided comparative analysis of a healthcare system that is not provided free of charge at the point of delivery to the entire population. Analyses were conducted using the 'framework approach' described by Rabiee (Focus-group interview and data analysis. Proc Nutr Soc 63, 655-660). There was a preference for services to be led by the government and delivered face-to-face, which was perceived to increase trust and transparency, and add value. Both countries associated paying for nutritional advice with increased commitment and motivation to follow guidelines. Contrary to Ireland, however, and despite the perceived benefit of paying, UK discussants still expected PN services to be delivered free of charge by the NHS. Consideration of this unique challenge of free healthcare that is embedded in the NHS culture will be crucial when introducing PN to the UK.

Recent developments in prebiotics to selectively impact beneficial microbes and promote intestinal health

Prebiotics are non-digestible food ingredients that have a specific stimulatory effect upon selected populations of gut bacteria. The usual target microorganisms for prebiotic approaches are bifidobacteria. Numerous human feeding studies have shown the prebiotic influences that galactans and fructans can exert. Other candidate prebiotics are under investigation. The field is now moving towards identifying the health aspect associated with their use. Many avenues of gut related health are being researched, including reduction of diarrhoea, immune stimulation, and improved mineral bioavailability. Most current emphasis appears to be towards various parameters associated with metabolic syndrome. These include markers of insulin resistance, appetite, satiety, blood lipids and inflammatory status.

Impact of palm date consumption on microbiota growth and large intestinal health: a randomised, controlled, cross-over, human intervention study

The reported inverse association between the intake of plant-based foods and a reduction in the prevalence of colorectal cancer may be partly mediated by interactions between insoluble fibre and (poly)phenols and the intestinal microbiota. In the present study, we assessed the impact of palm date consumption, rich in both polyphenols and fibre, on the growth of colonic microbiota and markers of colon cancer risk in a randomised, controlled, cross-over human intervention study. A total of twenty-two healthy human volunteers were randomly assigned to either a control group (maltodextrin-dextrose, 37·1 g) or an intervention group (seven dates, approximately 50 g). Each arm was of 21 d duration and was separated by a 14-d washout period in a cross-over manner. Changes in the growth of microbiota were assessed by fluorescence in situ hybridisation analysis, whereas SCFA levels were assessed using HPLC. Further, ammonia concentrations, faecal water genotoxicity and anti-proliferation ability were also assessed using different assays, which included cell work and the Comet assay. Accordingly, dietary intakes, anthropometric measurements and bowel movement assessment were also carried out. Although the consumption of dates did not induce significant changes in the growth of select bacterial groups or SCFA, there were significant increases in bowel movements and stool frequency (P<0·01; n 21) and significant reductions in stool ammonia concentration (P<0·05; n 21) after consumption of dates, relative to baseline. Furthermore, date fruit intake significantly reduced genotoxicity in human faecal water relative to control (P<0·01; n 21). Our data indicate that consumption of date fruit may reduce colon cancer risk without inducing changes in the microbiota.

Simulating the impact on health of internalising the cost of carbon in food prices combined with a tax on sugar-sweetened beverages

Rising greenhouse gas emissions (GHGEs) have implications for health and up to 30 % of emissions globally are thought to arise from agriculture. Synergies exist between diets low in GHGEs and health however some foods have the opposite relationship, such as sugar production being a relatively low source of GHGEs. In order to address this and to further characterise a healthy sustainable diet, we model the effect on UK non-communicable disease mortality and GHGEs of internalising the social cost of carbon into the price of food alongside a 20 % tax on sugar sweetened beverages (SSBs). Developing previously published work, we simulate four tax scenarios: (A) a GHGEs tax of £2.86/tonne of CO2 equivalents (tCO2e)/100 g product on all products with emissions greater than the mean across all food groups (0.36 kgCO2e/100 g); (B) scenario A but with subsidies on foods with emissions lower than 0.36 kgCO2e/100 g such that the effect is revenue neutral; (C) scenario A but with a 20 % sales tax on SSBs; (D) scenario B but with a 20 % sales tax on SSBs. An almost ideal demand system is used to estimate price elasticities and a comparative risk assessment model is used to estimate changes to non-communicable disease mortality. We estimate that scenario A would lead to 300 deaths delayed or averted, 18,900 ktCO2e fewer GHGEs, and £3.0 billion tax revenue; scenario B, 90 deaths delayed or averted and 17,100 ktCO2e fewer GHGEs; scenario C, 1,200 deaths delayed or averted, 18,500 ktCO2e fewer GHGEs, and £3.4 billion revenue; and scenario D, 2,000 deaths delayed or averted and 16,500 ktCO2e fewer GHGEs. Deaths averted are mainly due to increased fibre and reduced fat consumption; a SSB tax reduces SSB and sugar consumption. Incorporating the social cost of carbon into the price of food has the potential to improve health, reduce GHGEs, and raise revenue. The simple addition of a tax on SSBs can mitigate negative health consequences arising from sugar being low in GHGEs. Further conflicts remain, including increased consumption of unhealthy foods such as cakes and nutrients such as salt.

The impact of European legislative and technology measures to reduce air pollutants on air quality, human health and climate

European air quality legislation has reduced emissions of air pollutants across Europe since the 1970s, affecting air quality, human health and regional climate. We used a coupled composition-climate model to simulate the impacts of European air quality legislation and technology measures implemented between 1970 and 2010. We contrast simulations using two emission scenarios; one with actual emissions in 2010 and the other with emissions that would have occurred in 2010 in the absence of technological improvements and end-of-pipe treatment measures in the energy, industrial and road transport sectors. European emissions of sulphur dioxide, black carbon (BC) and organic carbon in 2010 are 53%, 59% and 32% lower respectively compared to emissions that would have occurred in 2010 in the absence of legislative and technology measures. These emission reductions decreased simulated European annual mean concentrations of fine particulate matter(PM2.5) by 35%, sulphate by 44%, BC by 56% and particulate organic matter by 23%. The reduction in PM2.5 concentrations is calculated to have prevented 80 000 (37 000–116 000, at 95% confidence intervals) premature deaths annually across the European Union, resulting in a perceived financial benefit to society of US$232 billion annually (1.4% of 2010 EU GDP). The reduction in aerosol concentrations due to legislative and technology measures caused a positive change in the aerosol radiative effect at the top of atmosphere, reduced atmospheric absorption and also increased the amount of solar radiation incident at the surface over Europe. We used an energy budget approximation to estimate that these changes in the radiative balance have increased European annual mean surface temperatures and precipitation by 0.45 ± 0.11 °C and by 13 ± 0.8 mm yr−1 respectively. Our results show that the implementation of European legislation and technological improvements to reduce the emission of air pollutants has improved air quality and human health over Europe, as well as having an unintended impact on the regional radiative balance and climate.