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1.
In this paper, the EU28 (EU27 and Croatia) water footprint of consumption (WFcons) for different diets is analysed: the current diet (REF, period 1996–2005), a healthy diet (DGE), a vegetarian (VEG) and combined (COM) diet. By far the largest fraction of the total WFcons (4815 lcd) relates to the consumption of edible agricultural goods (84%). The average EU28 diet is characterised by a too high energy intake and a too high ratio of animal to vegetal protein intake. For a healthy diet, the intake of some product groups should be reduced (sugar, crop oils, meat and animal fats) and of other product groups increased (vegetables and fruit). Especially the consumption of animal products accounts for high WF amounts. The three alternative diets result in a substantial reduction (−974 lcd or −23% for DGE, −1292 lcd or −30% for COM, −1611 lcd or −38% for VEG) of the WFcons for agricultural products with respect to the existing situation (REF, 4265 lcd). The reduction in meat intake contributes most to the WF reduction. Each of the specific WF components (green, blue and grey) shows a reduction similar to the observed reduction in the total WFcons. Regarding the total WFcons (green, blue and grey WFcons) as well as the WFcons without the grey WF component (green + blue WFcons) for agricultural products, the EU28 shifts from net virtual water (VW) importer for the REF and DGE diets to net exporter for the COM and VEG diets.  相似文献   

2.
BackgroundSince food metabolites are eliminated by the urinary tract, several studies have investigated the association between diet and bladder cancer risk. Recently, the World Cancer Research Fund International/American Institute for Cancer Research (WCRF/AICR) suggested a potential beneficial effect of some foods (mainly vegetables, fruit, and milk) in the development of bladder cancer. We investigated the association between food groups and bladder cancer risk, seeking insights into food diversity as well as meat cooking methods.MethodsData were derived from an Italian multicentre case–control study, conducted between 2003 and 2014, including 690 bladder cancer cases and 665 frequency-matched controls. Odds ratios (ORs) and the corresponding 95% confidence intervals (95%CIs) for various dietary aspects were estimated by unconditional logistic regression models adjusted for energy intake and the major known risk factors for bladder cancer.ResultsComparing the highest versus the lowest quartiles, consumption of vegetables (OR = 0.62; 95%CI: 0.44-0.88) and milk/yogurt (OR = 0.62; 95%CI: 0.44–0.87) reduced the risk of bladder cancer. Conversely, consumption of meat increased bladder cancer risk with an OR of 1.57 (95%CI: 1.07–2.31), particularly when the meat was stewed (OR = 1.47; 95%CI: 1.03–2.09) or roasted (OR = 1.41; 95%CI: 1.00–1.99). There was a suggestion that a diversified diet reduced the risk of bladder cancer, but this was not significant.ConclusionsOur study consolidates the role of diet in bladder cancer aetiology, showing a reduced risk for vegetable and milk/yogurt consumption and an increased risk for meat consumption, especially when the meat is stewed or roasted.  相似文献   

3.
Climate change, world population growth and industrialization have placed considerable stress on the local availability of water resources. Considering that most of the world's population currently resides in cities, this issue has particular relevance in an urban environment. One of the methods that is recognized to support better water management is water footprint accounting. However, due to the requirement of large amounts of data and their limited availability, applications of this method at an urban scale use national or regional water use data. The goal of this study is to develop a methodological proposal to assess the water footprint accounting of direct water use at an urban level to support the local management of water resources by using local data, by adopting a bottom-up approach and by verifying its applicability in a real case study. The water footprint accounting approach was modified by adopting a modular approach in the definition of boundaries and by adapting the blue, green and gray water footprint accounting formulations. The proposed method was successfully tested in the municipality of Vicenza (north east Italy) and provided interesting responses in terms of water management. Herein, we also discuss the latest developments in impact assessments related to water based on a life cycle assessment, which should be used as a framework for the future development of the model that is presented.  相似文献   

4.
This study examined the effect of subcutaneous administration of the neurohormone oxytocin on water intake of ad lib-fed (with or without sodium availability in the diet) and food-deprived animals. Results of the first experiment showed that oxytocin increased water intake and urine excretion in food-deprived but not in ad lib-fed animals. However, oxytocin treatment did not modify the reduced water "balance" (fluid intake minus urine volume) resulting from food deprivation or the daily food intake (Experiment 1). The dose-dependent polydipsic effect of oxytocin on food-deprived rats was always preceded by an increase in sodium and fluid urine excretion (Experiment 2). Oxytocin also increased the water intake of animals fed ad lib with a low sodium diet (Experiment 3). These results suggest that the effect of oxytocin on water intake is dependent on the presence or absence of sodium in the diet and that the excretion of sodium is the main mechanism of oxytocinergic polydipsia in food-deprived male rats.  相似文献   

5.
The 3568 final class primary school in northwestern Poland were investigated between January and June 2000. The youths fulfilled the questionnaire concerned health behaviour issues. The 56% of school children do not drink milk daily, 68% do not eat raw vegetables, and 35% do not take any food at school. Every second boy and every fourth girl brushes his/her teeth too rarely. 23% of boys and 10% of girls smoke cigarettes. About 30% of boys and 20% of girls declare that it “happens” that they drink alcohol. 15% boys and 8% of girls report that they tried to use at least one of the psychoactive substances. Physical exercises are performed by 28% of boys and 36% of girls and 45% and 28% respectively watch TV four or more hours a day.  相似文献   

6.
Meat production puts larger demands on water and land and results in larger greenhouse gas emissions than alternative forms of food. This study uses footprint indicators, the water, land and carbon footprint, to assess natural resources use and greenhouse gas emissions for sheep and chicken meat produced in Tunisia in different farming systems in the period 1996–2005. Tunisia is a water-scarce country with large areas of pasture for sheep production. Poultry production is relatively large and based on imported feed. The farming systems considered are: the industrial system for chicken, and the agro-pastoral system using cereal crop-residues, the agro-pastoral system using barley and the pastoral system using barley for sheep. Chicken meat has a smaller water footprint (6030 litre/kg), land footprint (9 m2/kg) and carbon footprint (3 CO2-eq/kg) than sheep meat (with an average water footprint of 18900 litre/kg, land footprint of 57 m2/kg, and carbon footprint of 28 CO2-eq/kg). For sheep meat, the agro-pastoral system using cereal crop-residues is the production system with smallest water and land footprints, but the highest carbon footprint. The pastoral system using barley has larger water and land footprints than the agro-pastoral system using barley, but comparable carbon footprint.  相似文献   

7.
Assessments of urban metabolism (UM) are well situated to identify the scale, components, and direction of urban and energy flows in cities and have been instrumental in benchmarking and monitoring the key levers of urban environmental pressure, such as transport, space conditioning, and electricity. Hitherto, urban food consumption has garnered scant attention both in UM accounting (typically lumped with “biomass”) and on the urban policy agenda, despite its relevance to local and global environmental pressures. With future growth expected in urban population and wealth, an accounting of the environmental footprint from urban food demand (“foodprint”) is necessary. This article reviews 43 UM assessments including 100 cities, and a total of 132 foodprints in terms of mass, carbon footprint, and ecological footprint and situates it relative to other significant environmental drivers (transport, energy, and so on) The foodprint was typically the third largest source of mass flows (average is 0.8 tonnes per capita per annum) and carbon footprint (average is 2.1 tonnes carbon dioxide equivalents per capita per annum) in the reviewed cities, whereas it was generally the largest driver of urban ecological footprints (average is 1.2 global hectares per capita per annum), with large deviations based on wealth, culture, and urban form. Meat and dairy are the primary drivers of both global warming and ecological footprint impacts, with little relationship between their consumption and city wealth. The foodprint is primarily linear in form, producing significant organic exhaust from the urban system that has a strong, positive correlation to wealth. Though much of the foodprint is embodied within imported foodstuffs, cities can still implement design and policy interventions, such as improved nutrient recycling and food waste avoidance, to redress the foodprint.  相似文献   

8.
L Pénicaud  D A Thompson 《Life sciences》1984,35(23):2297-2302
In order to examine the role and site of action of opiates on both hunger and thirst and food and water intake in rats after short term (3 hr.) food deprivation alone or in combination with 2DG-induced glucoprivic stress, naloxone was given to rats in either the jugular vein or the lateral ventricle. Both basal and 2DG-induced food and water intake were reduced by naloxone injected either peripherally or centrally. Latencies to eat and drink were used as measures of hunger and thirst respectively. Only central injection of naloxone significantly reduced 2DG-induced but not basal hunger. These results suggest a central site of action of naloxone on both food and water intake even if some peripheral effects cannot be totally ruled out. Our findings indicate central nervous system opiate receptor involvement in the hunger response to 2DG-induced glucoprivation. In all other treatment conditions, decreases in food intake cannot be related to reduction of hunger but may be due to potentiation of satiation during opiate receptor blockade.  相似文献   

9.
The control of food intake and satiety requires a coordinated interplay. Oral protein and duodenal fat inhibit food intake and induce satiety, but their interactive potential is unclear. Our aim was therefore to investigate the interactions between an oral protein preload and intraduodenal (ID) fat on food intake and satiety feelings. Twenty healthy male volunteers were studied in a randomized, double-blind, four-period crossover design. On each study day, subjects underwent one of the following treatments: 1) water preload plus ID saline perfusion, 2) water preload plus ID fat perfusion, 3) protein preload plus ID saline perfusion, or 4) protein preload plus ID fat perfusion. Subjects were free to eat and drink as much as they wished. An oral protein preload significantly reduced caloric intake (19%, P < 0.01). Simultaneous administration of an oral protein preload and ID fat did not result in a positive synergistic effect with respect to caloric consumption, rejecting the initial hypothesis that the two nutrients exert a positive synergistic effect on food intake. An oral protein preload but not ID fat altered the feelings of hunger and fullness. These data indicate that the satiety effect of an oral protein preload is not amplified by ID fat; indeed, the effect of a protein preload does not seem to be mediated by cholecystokinin, glucagon-like peptide-1, or peptide YY. Much more information is necessary to understand the basic physiological mechanisms that control food intake and satiety.  相似文献   

10.
In an experiment in which rats were allowed free access to food and water, the rats did not eat the diet containing a mushroom Pleurotus ostreatus even if they were emaciated. A P. ostreatus lectin (POL) was isolated from the mushroom as the food intake-suppression principle. In hemagglutination inhibition assays, Me-alphaGalNAc was the most potent inhibitor among the monosaccharides tested. Among all the sugars tested, 2'-fucosyllactose (Fucalpha1-->2Galbeta1-->4Glc) was the strongest inhibitor and its inhibitory potency was five times greater than that of Me-alphaGalNAc. POL exhibited a binding ability to bovine submaxillary mucin (BSM) and asialo-BSM and the other glycoproteins were inert to the binding. The food intake-suppressing activity of POL was dependent on the dose. The diet containing 0.1% POL caused a 50% decrease in the food intake of rats against the control.  相似文献   

11.
F. P. O'Mara 《Annals of botany》2012,110(6):1263-1270

Background

Grasslands are a major part of the global ecosystem, covering 37 % of the earth''s terrestrial area. For a variety of reasons, mostly related to overgrazing and the resulting problems of soil erosion and weed encroachment, many of the world''s natural grasslands are in poor condition and showing signs of degradation. This review examines their contribution to global food supply and to combating climate change.

Scope

Grasslands make a significant contribution to food security through providing part of the feed requirements of ruminants used for meat and milk production. Globally, this is more important in food energy terms than pig meat and poultry meat. Grasslands are considered to have the potential to play a key role in greenhouse gas mitigation, particularly in terms of global carbon storage and further carbon sequestration. It is estimated that grazing land management and pasture improvement (e.g. through managing grazing intensity, improved productivity, etc) have a global technical mitigation potential of almost 1·5 Gt CO2 equivalent in 2030, with additional mitigation possible from restoration of degraded lands. Milk and meat production from grassland systems in temperate regions has similar emissions of carbon dioxide per kilogram of product as mixed farming systems in temperate regions, and, if carbon sinks in grasslands are taken into account, grassland-based production systems can be as efficient as high-input systems from a greenhouse gas perspective.

Conclusions

Grasslands are important for global food supply, contributing to ruminant milk and meat production. Extra food will need to come from the world''s existing agricultural land base (including grasslands) as the total area of agricultural land has remained static since 1991. Ruminants are efficient converters of grass into humanly edible energy and protein and grassland-based food production can produce food with a comparable carbon footprint as mixed systems. Grasslands are a very important store of carbon, and they are continuing to sequester carbon with considerable potential to increase this further. Grassland adaptation to climate change will be variable, with possible increases or decreases in productivity and increases or decreases in soil carbon stores.  相似文献   

12.
Food intake and physical activity are regulated by multiple neuropeptides, including orexin and dynorphin (DYN). Orexin-A (OXA) is one of two orexin peptides with robust roles in regulation of food intake and spontaneous physical activity (SPA). DYN collectively refers to several peptides, some of which act through opioid receptors (opioid DYN) and some whose biological effects are not mediated by opioid receptors (non-opioid DYN). While opioid DYN is known to increase food intake, the effects of non-opioid DYN peptides on food intake and SPA are unknown. Neurons that co-express and release OXA and DYN are located within the lateral hypothalamus. Limited evidence suggests that OXA and opioid DYN peptides can interact to modulate some aspects of behaviors classically related to orexin peptide function. The paraventricular hypothalamic nucleus (PVN) is a brain area where OXA and DYN peptides might interact to modulate food intake and SPA. We demonstrate that injection of des-Tyr-dynorphin (DYN-A2−17, a non opioid DYN peptide) into the PVN increases food intake and SPA in adult mice. Co-injection of DYN-A2−17 and OXA in the PVN further increases food intake compared to DYN-A2−17 or OXA alone. This is the first report describing the effects of non-opioid DYN-A2−17 on food intake and SPA, and suggests that DYN-A2−17 interacts with OXA in the PVN to modulate food intake. Our data suggest a novel function for non-opioid DYN-A2−17 on food intake, supporting the concept that some behavioral effects of the orexin neurons result from combined actions of the orexin and DYN peptides.  相似文献   

13.
城市食物源氮消费产生的环境排放是全国氮污染的重要源头,城市食物氮足迹评估可反映维持城市人口基本食物需求的活性氮排放以及对周边环境的潜在影响。以典型移民城市深圳市为例,基于改进N-Calculator模型的基础上,估算了2010-2015年间因城市人口流动导致的城市食物氮足迹变化,并分析其时空异质性及其与城市化间的关系。结果表明:深圳市不同类型城市居民食物氮足迹不一致,其中常住户籍居民人均食物氮足迹从14.63 kg N a-1增加至15.17 kg N a-1,高于非户籍居民食物氮足迹13.09 kg N a-1,其主要体现在瓜果、肉类、水产品等食物消费上。总体上,深圳城市食物氮足迹呈增长趋势,5年增幅11.50%,增幅最大为常住户籍居民食物氮足迹,但目前深圳非户籍居民的食物消费主导着城市食物氮足迹。深圳城市内部区域食物氮足迹呈高度空间异质性与聚集性,各区域增长量差异明显,街道尺度城市食物氮足迹增长热点主要分布在城市的西部沿海区域,部分热点区域单位增长量数量级比肩区级尺度单位的增长量,城市区域食物氮足迹与人口城市化的关联性不明显,但与经济城市化存在一定的关联性。当前城市移民落户趋势及居民高氮饮食倾向不利于城市氮足迹的削减,减少食物生产上游活性氮流失为深圳市贯彻粤港澳大湾区协同可持续发展的关键。  相似文献   

14.
Bottle choice tests using liquid diets were done with Sprague-Dawley (SD) rats. SD rats ingested more oil-and-sucrose-enriched milk (hi-fat) and less oil-enriched milk (hi-fat-no-carb) than sucrose-enriched (hi-carb) milk by two-bottle choice tests after they were habituated to liquid diets for 4 days. Chronic food restriction didn't increase hi-fat ingestion but hi-fat-no-carb. Rats ingested less without habituation, and overnight food deprivation increased intake. This increment was maintained after rats were free-fed. The difference in fat content of the maintenance diet had little effect on fat preference. These results showed SD rats prefer a sweet and fatty liquid diet than a sweet and lean liquid diet. Habituation and food restriction were more important than the composition of the maintenance diet to demonstrate a clear preference for the fatty liquid diet.  相似文献   

15.
Bottle choice tests using liquid diets were done with Sprague-Dawley (SD) rats. SD rats ingested more oil-and-sucrose-enriched milk (hi-fat) and less oil-enriched milk (hi-fat-no-carb) than sucrose-enriched (hi-carb) milk by two-bottle choice tests after they were habituated to liquid diets for 4 days. Chronic food restriction didn't increase hi-fat ingestion but hi-fat-no-carb. Rats ingested less without habituation, and overnight food deprivation increased intake. This increment was maintained after rats were free-fed. The difference in fat content of the maintenance diet had little effect on fat preference. These results showed SD rats prefer a sweet and fatty liquid diet than a sweet and lean liquid diet. Habituation and food restriction were more important than the composition of the maintenance diet to demonstrate a clear preference for the fatty liquid diet.  相似文献   

16.
Past positive experiences can increase herbivores’ motivation to eat low-quality foods. However, this is not always translated into a higher preference for low-quality foods in choice tests among foods of higher nutritional quality. Foraging behavior is also affected by properties of the feeding context because the quality and abundance of foods in nature change in time and space. We hypothesized that in a choice situation, the expression of a past positive experience with a low-quality food is modulated by the costs associated with selecting a high-quality food option. A total of 24 sheep were randomly assigned into two groups (n=12). During conditioning phase, one group (CS+; i.e., conditioned group) was fed with oat hay (a low-quality food) for 20 min and immediately after a ration of soybean meal (a nutritious food), whereas the other group was also fed with oat hay but the offer of soybean meal was delayed 5 h (CS−; i.e., control group). After conditioning, we assessed sheep motivation to eat the oat hay in an experimental arena in which accessibility to alfalfa hay (a high-quality food) was increasingly restricted. When alfalfa hay was readily accessible, CS+ and CS− sheep almost exclusively selected this food, showing a small and similar preference for oat hay. However, when accessibility to alfalfa hay decreased, intake and selection of oat hay was greater in the CS+ sheep than in the CS− sheep. The latter was a consequence of differential changes in behavior between groups; for example, sheep in CS+ spent more time foraging oat hay and were more likely to switch to oat hay if they had previously been eating alfalfa hay than sheep in CS−. Our results show that behavioral expression of the conditioned preference for a low-quality food depends on parameters of the feeding context (e.g., availability). We suggest that this can be the link between learning models and optimal foraging models of diet selection.  相似文献   

17.
Indian free-ranging dogs live in a carbohydrate-rich environment as scavengers in and around human settlements. They rarely hunt and consequently do not encounter rich sources of protein. Instead, they have adapted to a diet of primarily carbohydrates. As descendents of the exclusively carnivorous wolves, they are subjected to the evolutionary load of a physiological demand for proteins. To meet their protein needs, they resort to a Rule of Thumb—if it smells like meat, eat it. Pups face high competition from group and non-group members and are in a phase of rapid growth with high protein demands. Following the Rule of Thumb, they can acquire more protein at the cost of increased competition and reduced supplementary non-protein nutrition. However, if the mother supplements their diet with protein-rich regurgitates and/or milk, then the pups can benefit by being generalists. Using a choice test in the field, we show that, while adults have a clear preference for meat, pups have no such preference, and they even eagerly eat degraded protein. Thus, the Rule of Thumb used by adult dogs for efficient scavenging is not innate and needs to be learned. The Rule of Thumb might be acquired by cultural transmission, through exposure to meat in the mother’s regurgitate, or while accompanying her on foraging trips.  相似文献   

18.
Food selection was studied in free living green iguanas (Iguana iguana) throughout the year in a semiarid environment, Curaçao (Netherlands Antilles). Food intake was determined by direct observations and converted into biomass intake. Comparison between intake and biomass availability of the various food items revealed that the lizards were selective, and that changes in seasonal food availability led to periodic switching of food plants. The extent to which nutrient constraints determine iguana feeding ecology was investigated. Potential constraints were the requirements for water, digestible crude protein, and metabolizable energy. By using a linear programming model that incorporates characteristics of the food (chemical composition, energy content, item size) and requirements and constraints of the green iguanas (nutrient and energy requirements digestive tract capacity, feeding rate) it was possible to identify which factors determine food choice over the year. During the dry period, when the iguanas had no access to drinking water they consumed flowers to increase water intake, though the amount of flowers consumed was too low to cover maintenance requirements for either energy or protein. After the young leaf flush, following the early rains in May, the biomass increased, free surface water was available during showers, and the linear programming solutions indicate that food selection conformed to the protein maximization criterion. Reproduction in green iguanas shows an annual cycle, in which oviposition takes place at the end of the dry season, when intake is below maintenance levels. Females show a 8–10 month gap between acquisition of most of the protein required for egg synthesis and the act of laying. Thus, as in avian and mammalian herbivores, food availability during a period prior to the energy and protein demanding reproductive season of iguanas determines reproductive success.  相似文献   

19.
McFarland (1969) suggested two mechanisms whereby a switch could occur from one activity to another: ‘competition’, which he depicted as a gradual increase in the causal-factor strength (CFS) of activity 2, and ‘disinhibition’, which he depticted as a sudden decrease in the CFS of activity 1. We postulate two further mechanisms: ‘satiation’, depicted as a gradual decrease in the CFS of activity 1, and ‘inhibition’, depicted as a sudden increase in the CFS of activity 2. We suggest that disinhibition may be a less common mechanism of behavioural switching than is usually supposed, and describe three experiments suggesting that eat/drink and drink/eat switches in the rat occur by competition and/or satiation rather than by disinhibition and/or inhibition. In experiment 1, varying degrees of water deprivation were found to affect the timing of eat/drink switches in food-deprived rats; in experiment 2, varying rates of food availability were found to affect the timing of drink/eat switches in water-deprived rats; in experiment 3, drink/eat switches were delayed by allowing rats to ‘drink’ air instead of water.  相似文献   

20.

Background

In the Nordic countries, substantial policy and intervention efforts have been made to increase adolescents'' consumption of fruit and vegetables and to reduce their intake of sweets and soft drinks. Some initiatives have been formulated in a Nordic collaboration and implemented at national level. In recent years, social inequalities in food habits have been attracted particular governmental interest and several initiatives addressing the socioeconomic gradient in food habits have been highlighted. However, few internationally published studies have evaluated how trends in adolescents'' food habits develop in the context of Nordic nutrition policy, or have compared differences between the Nordic countries.

Methods

The study was based on Danish, Finnish, Norwegian and Swedish cross-sectional data from the international Health Behaviour in School-Aged Children (HBSC) study, collected via three nationally representative and comparable questionnaire surveys in 2001/2002, 2005/2006 and 2009/2010. Food habits were identified by students'' consumption of fruit, vegetables, sweets and sugar sweetened soft drink. Socioeconomic status (SES) was measured with the Family Affluence Scale (FAS). Multilevel logistic regression was used to analyze the data.

Results

Trends in fruit consumption developed differently across countries, characterized by an increase in Denmark and Norway and more stable trends in Sweden and Finland. Vegetable consumption increased particularly in Denmark and to a lesser extent in Norway, whereas Sweden and Finland displayed stable trends. Decreased trends were observed for sweet and soft drink consumption and were similar in Norway, Sweden and Finland. Sweet consumption decreased across all survey years, whereas soft drink consumption decreased between 2001/2002–2005/2006 and was stable thereafter. Denmark displayed an increase between 2001/2002–2005/2006 followed by a similar decrease between 2005/2006–2009/2010 for both sweet and soft drink consumption. Socioeconomic inequalities in fruit and vegetable consumption were observed in all countries, with no cross-country differences, and no changes over time. Small but not significant cross-country variation was identified for SES inequalities in sweet consumption. Reduced SES inequalities were observed in Sweden between 2005/2006 and 2009/2010. SES was not associated with soft drink consumption in this study population, with the exception of Denmark for the survey year 2009/2010.

Conclusion

Different trends resulted in increased country differences in food habits during the time of observations. In survey year 2009/2010, Danish students reported a higher intake of fruit and vegetable consumption than their counterparts in the other Nordic countries. Finnish students reported the lowest frequency of sweets and soft drink consumption. Despite the positive dietary trends documented in the present study, the majority of Nordic adolescents are far from meeting national dietary recommendations. Our findings underline the need for more comprehensive initiatives targeting young people''s food habits as well as a more deliberate and focused action to close gaps in social inequalities that affect food choices.  相似文献   

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