Unbalanced Foods Research Articles

L’alimentation entre éthique, science et innovation

The digital advertising environment influences children’s food choices in a context of over-representation of fatty, sweet and salty products. Restricting this influence proves complex, given the variety and novelty of the marketing techniques used, subject to legal regimes that combine traditional branches of market law with new rules specific to the digital environment. Despite the assertion of children’s rights in relation to the digital environment, minors and their health are not sufficiently protected. Few rules exist (ban on concealed advertising, health messages, targeting of children’s advertising, etc.), and none really limits children’s exposure to digital advertising for nutritionally unbalanced foods.

Quality Attributes and Sensory Acceptance of Different Botanical Coffee Co-Products.

Coffee processing is a major contributor to the creation of food and product waste. Using coffee co-products can play an essential role in addressing environmental problems and issues with nutritionally unbalanced foods, population growth, and food-related diseases. This research aimed to determine the quality and sensory parameters (aw, pH, dry matter, TAC, TPC, fat, fatty acids profile, fiber, caffeine, chlorogenic acids, color, and sensory analysis) of different botanical origins of cascara (coffee husks) and silverskin (thin layer). The results of this study show that silverskin and cascara are a good source of TAC (1S 58.17 ± 1.28%, 2S 46.65 ± 1.20%, 1C 36.54 ± 1.84%, 2C 41.12 ± 2.11%). Cascara showed the presence of polyphenols (2C 49.135 g GAE·kg-1). Coffee co-products are good sources of fiber. Silverskin had higher values of caffeine than cascara. Palmitic, stearic, oleic, linoleic, and arachidic acids were the most represented acids in the samples. Given the obtained results, cascara can be considered "low-fat" (1C 4.240 g·kg-1 and 2C 5.4 g·kg-1). Based on the sensory evaluation, no sample reached the acceptable index value of 70%. Understanding the link between the character, identification properties, and composition of coffee co-products of different botanical origins can enable their application in the food industry.

The Impact of Social Well-Being on Population Diet Nutritional Value and Antiradical Status.

The paper presents the result of assessing the antiradical status of consumers (in the context of Russia) in connection with their well-being. This approach is based on a multistage study, in which the results of sociological surveys were applied, as well as estimates of the antiradical potential (ARP) of diets obtained using neural networks, bootstrapping the chemical composition of diets, and calculating reference values using mathematical models. The paper presents data collected from residents living in the territories of at least 21 regions and cities of Russia: Magadan, Saint Petersburg, Moscow, Krasnodar, Lipetsk, Vladivostok, Novosibirsk, Omsk, Voronezh, etc. A total of 1001 people were interviewed, which, according to our calculations, gives a margin of error in value of approximately 3.1%. To calculate the lack of vitamins in the diets of residents of the Russian Federation, data on the chemical composition of food products from the FNDDS database were used. The assessment of dietary habits showed a lack of vitamins below the recommended level in 73% of Russians for vitamin D, 59% for retinol, 38% for β-carotenes, 13% for vitamin E, and 6% for ascorbic acid. The study showed that at least 36% of the Russian population has a low antiradical status, while it was found that "poor" consumers are more likely to consume economically more expensive foods (in terms of their nutritional value). The "poor" segments of the population consume 180-305% more canned food and 38-68% more sweet carbonated drinks than other social groups, but their consumption of vegetables is 23-48% lower. On the contrary, "wealthy" consumers consume 17-25% more complex (varied) dishes, 10-68% more fresh vegetables, and 8-39% more fish. From the obtained values it follows that consumers with low levels of ARP in their diets are in a group with an increased probability of a number of "excess" diseases (diseases of the cardiovascular system, obesity, etc.). In general, the ARP values of food consumed for low-income segments of the population were 2.3 times lower (the ratio was calculated as the percentage of consumers below the level of 11,067 equivalents necessary for the disposal of free radicals generated in the human body per day) than for those who can afford expensive food (consumers with high income). A simple increase in consumption of unbalanced foods, in our opinion, will only contribute to the entry of these consumers into the "average diet trap". All this makes it imperative to develop comprehensive measures to create a new concept of public catering; otherwise, we can expect a reduction in both the health of the population and the performance of the economy of the whole country.

Nutritional Status of Children with Severe Malnutrition in Elnohoud Educational Hospital in West Kordofan State, Sudan

The present work was conducted in Elnohoud educational hospital, West Kordofan State, Sudan during the period from 2015 – 2017. The aim of the study was to identify the nutritional status among children less than five years of age. Study included 100 children. Data were collected using a structural interview questionnaire, then analyzed via the Statistical Package for Social Sciences (SPSS) software version 16. The results indicated that the majority of patients (73%) in age group of 13-24 months, and their resident in rural areas (94%) and belonged to large families' more than six family members (56%), also the birth spacing were 74% less than one year and 26% were more than one year. 84% of the mothers were housewives, while 70% of fathers were farmers and workers. and 71% of mothers were more than 24 years old. 70% of the malnourished children received insufficient breastfeeding mainly due to pregnancy or mother's illness. Nearly (89%) were introduced to supplementary food with breastfeeding before 6 months, and (75%) of surveyed received less than three meals/day of unbalanced inferior quality foods (88%). Additionally 66% of studied children used the traditional treatments such as razor cut, fire and hilba for diseases control. Also 58% of the studied children had cases of sickness previously admittance to hospital two times. A cause of nutritional status of Children with severe malnutrition problems in another places of Kordofan regions rather than Elnuhoud educational hospital need to be elaborated in future work as recommended point of view.

Daily lifestyle behaviors and risks of sarcopenia among older adults

BackgroundLifestyle behaviors are modifiable factors that can provide information for designing intervention strategies for sarcopenia. The present study aimed to identify the relationships between a range of daily lifestyle behaviors and sarcopenia risks among older adults.MethodsA nationwide telephone-based survey targeting older adults (≥65 years) was performed in Taiwan. Data based on self-reported daily lifestyle behaviors (food selection, physical activity, sitting time, and sleep duration), the presence or absence of sarcopenia (measured by SARC-F), and personal characteristics were obtained. Binary logistic regression models were applied.ResultsA total of 1068 older adults participated in this survey. In the adjusted model, older adults who selected unbalanced foods (odds ratio [OR] = 1.93, 95% confidence interval [CI] = 1.12–3.34), engaged in insufficient physical activity (OR = 5.14, 95% CI = 3.04–8.70), and sat for longer periods of time (OR = 1.98, 95% CI = 1.09–3.59) were more likely to have higher risks of sarcopenia. No significant association was observed for sleep duration.ConclusionsThe results of this study highlight that, among health behaviors, an unbalanced food selection (six nutrients), not meeting physical activity recommendations (150 min/week), and a higher sitting time (≥7 h/day) were risk factors for sarcopenia among older adults. Intervention programs for sarcopenia prevention in older adults should focus on promoting balanced food selection, sufficient physical activity, and reduced sitting time.

Relationship of Habits Eat Fast Food and Macro Nutrition Substance with Nutritional Status of The Students of Makassar 16 Junior High School

Lifestyle influencesform of behavior or habits a person in responding to physical and psychological, environmental, social, cultural and economic endurance. One of them is a change in people's behavior in eating patterns in the lives of teenagers now results in changes in nutritional status because they tend to consume unbalanced foods and increase the number of nutritional risks. Factor for teenagers who want to eat fast food often, which is available in some parts of the school. As a result of Behavioral Changes, some teenagers experience changes nutritional status that needed attention. The purpose of this study is to determine the relationship between fast food eating habits and macro nutrient intake with nutritional status of the students of Makassar 16 Junior High School. The study use a cross sectional study design with an analytical approach. This study uses statistical analysis, the chi-square test of the number of samples as much as 89. The habit of eating fast food is obtained from the food frequency questionnaire by adding the score of each food ingredient then compared with the average score of the total score of all subjects. Intake of macro nutrients is obtained from 2x24 hour form recall. Nutritional status is obtained by weighing and body weight then calculated using BMI. The data is presented in the form of graphs and narratives. The results showed that fast food eating habits tended several times (50.6%), and macro nutrient intake was generally good (52.8%). Nutritional status according to normal BMI was 47 people (52.8%) who had thin nutritional status of 32 people (36%), and those who had fat nutritional status were 10 people (11.2%). There is no relationship between the habit of eating fast food with nutritional status, and there is a relationship between macro nutrient intake and nutritional status values.

Nutritional Cues Tie Living Organisms to Their Environment and Its Sustainability.

We connect modern, intensive agriculture’s role in environmental degradation to its role in producing nutritionally unbalanced foods, and delineate specific approaches to reduce agriculture’s environmental impact, while producing healthful foods. We call attention to recently discovered genetic programs used by all living organisms to respond to their environment, and present a model of how these programs change body composition and function (of humans and their crop plants and livestock alike) in response to environmental cues. We propose that production of nutritionally balanced crops and livestock requires careful consideration of how these plants and animals are grown; the composition of plant food is modulated by growing conditions, body composition of livestock reflects their feed; composition and function of human body and brain are strongly affected by how food plants and animals are produced. We selected four nutritional features not only involved in (i) governing human health by modulating these genetic programs, but (ii) also affected by agricultural practices. These nutritional features are fat composition (especially saturated fat and the ratio of polyunsaturated omega-6 oils to omega-3 oils), carbohydrate composition (especially the proportion of carbohydrates with a high glycemic index, such as sugars and quick-burning starches) and the level of antioxidant micronutrients. We not only outline threats to human health presented by the current environment, but also potential gains in quality-of-life in a future environment designed to optimize human wellness using insights into the gene-programing effect of diet- and other lifestyle-related factors. These gains could extend beyond optimal human physical and mental health to gains in workforce productivity. The same changes in agricultural practices required to achieve these gains in human health are also needed to support environmental health and sustainable food production. The resulting vision of optimal human health and environmental health, supported by sustainable practices, is intended as an inspiring image of what sustainability has to offer to individuals and society. Our goal is to provide a transparent overview and illustrations intelligible not only to non-experts in each of the other respective areas involved but also to policy makers and the public.

Improvement of the healthy properties of a Spanish artisan meat pie maintaining the organoleptic quality

Some artisan products with high fat content, particularly saturated fat, are perceived as unbalanced foods. The “Murcia's meat pie” (MMP) is a Spanish artisan product with ground beef as the main filling ingredient. The aim of this study was to improve the healthy properties of MMP maintaining its original organoleptic quality. Four MMP which were different in the proportion and anatomic location of the cuts of beef were assessed. The MMP most recommended for human consumption was elaborated with ground beef prepared with neck (20 g/100 g) and chuck (80 g/100 g) because of having a lower fat content than the control (37 g/100 g) and the most recommended fatty acid profile. The study showed that a better selection of one or more ingredients can be a valuable strategy for improving the healthy properties of artisan products, without diminishing the sensory attributes. This would allow maintaining the identity, cultural and gastronomic heritage of each country.

Genetic Resistance to Bacillus thuringiensis Alters Feeding Behaviour in the Cabbage Looper, Trichoplusia ni

Evolved resistance to xenobiotics and parasites is often associated with fitness costs when the selection pressure is absent. Resistance to the widely used microbial insecticide Bacillus thuringiensis (Bt) has evolved in several insect species through the modification of insect midgut binding sites for Bt toxins, and reports of costs associated with Bt resistance are common. Studies on the costs of Bt-resistance restrict the insect to a single artificial diet or host-plant. However, it is well documented that insects can self-select appropriate proportions of multiple nutritionally unbalanced foods to optimize life-history traits. Therefore, we examined whether Bt-resistant and susceptible cabbage loopers Trichoplusia ni differed in their nutrient intake and fitness costs when they were allowed to compose their own protein:carbohydrate diet. We found that Bt-resistant T. ni composed a higher ratio of protein to carbohydrate than susceptible T. ni. Bt-resistant males exhibited no fitness cost, while the fitness cost (reduced pupal weight) was present in resistant females. The absence of the fitness cost in resistant males was associated with increased carbohydrate consumption compared to females. We demonstrate a sex difference in a fitness cost and a new behavioural outcome associated with Bt resistance.

전공 여부에 따른 남대생의 신체발달, 영양상태 및 건강생활습관에 관한 연구

Abstract This study was conducted to obtain principal data on nutrition education according to college major after analyzing the nutrition status of 302 male university subjects. The 302 male subjects consisted of male students majoring in literature and science (109), food and nutrition (94), and physical education (99). Exactly 47.9% (highest among the groups) of male students majoring in food and nutrition ate regular meals, 39.4% ate breakfast. Precisely 29.4% of subjects majoring in literature and science never ate out. Exactly 23.2% of subjects majoring in physical education over ate frequently, and 31.3% enjoyed eating out. Intakes of protein, fat, vitamin A, B 1 , B 2 , B 6 , C, E, folic acid, Ca, Fe, sodium, and cholesterol among male students majoring in food and nutrition appeared to be significantly higher compared to those of other groups (p<0.05). Intakes of energy, Zn, dietary fiber, and cholesterol among male students majoring in physical education were higher, whereas intakes of all nutrients except for dietary fiber by subjects majoring in literature and science were lower than the other two groups. Exactly 20.2% of male students were interested in health. We found that 52.4% of subjects considered exercise as an important factor for maintaining health. Smoking rate was the highest (43.6%) among male students majoring in nutrition, and the drinking rate was highest (56.0%) among male students majoring in literature and science. We found that smoking was continued as a habit (61.5%) while drinking was essential for social relationships (73.9%). From this study, it was found that male students have problems associated with eating regular meals, skipping breakfast, overeating, and intake of unbalanced foods. Also, male students who majored in food and nutrition demonstrated problems in applying their knowledge to proper dietary habits. In conclusion, a systemic educational program needs to be introduced to promote healthful dietary habits in male students.Key words: male students, eating habits, nutrient intakes, health

VProtein: identifying optimal amino acid complements from plant-based foods.

BackgroundIndispensible amino acids (IAAs) are used by the body in different proportions. Most animal-based foods provide these IAAs in roughly the needed proportions, but many plant-based foods provide different proportions of IAAs. To explore how these plant-based foods can be better used in human nutrition, we have created the computational tool vProtein to identify optimal food complements to satisfy human protein needs.MethodsvProtein uses 1251 plant-based foods listed in the United States Department of Agriculture standard release 22 database to determine the quantity of each food or pair of foods required to satisfy human IAA needs as determined by the 2005 daily recommended intake. The quantity of food in a pair is found using a linear programming approach that minimizes total calories, total excess IAAs, or the total weight of the combination.ResultsFor single foods, vProtein identifies foods with particularly balanced IAA patterns such as wheat germ, quinoa, and cauliflower. vProtein also identifies foods with particularly unbalanced IAA patterns such as macadamia nuts, degermed corn products, and wakame seaweed. Although less useful alone, some unbalanced foods provide unusually good complements, such as Brazil nuts to legumes.Interestingly, vProtein finds no statistically significant bias toward grain/legume pairings for protein complementation. These analyses suggest that pairings of plant-based foods should be based on the individual foods themselves instead of based on broader food group-food group pairings. Overall, the most efficient pairings include sweet corn/tomatoes, apple/coconut, and sweet corn/cherry. The top pairings also highlight the utility of less common protein sources such as the seaweeds laver and spirulina, pumpkin leaves, and lambsquarters. From a public health perspective, many of the food pairings represent novel, low cost food sources to combat malnutrition. Full analysis results are available online at http://www.foodwiki.com/vprotein.

The link between diet and health: an exploratory study of adolescents in Northern Ireland using foodmaps

AbstractA significant proportion of consumers in the UK continue to adopt a diet consisting largely of nutritionally unbalanced foods. The adolescent period has been identified as being formative in the development of long‐term eating habits as the individual achieves greater control over their food choice. By examining the current eating behaviour of a sample of adolescents, the aim of this study was to establish why they are not utilizing their knowledge to choose nutritionally balanced foods. A two‐stage data collecting procedure was adopted. In stage 1, respondents (n = 136) completed a questionnaire that measured demographic and social factors, knowledge, attitudes, pre‐existing behaviour with respect to food and the influence of family, peers, the media and government campaigns on their eating behaviour. In stage 2, a subsection of the respondents (n = 20) completed a foodmap, which revealed the network of relationships involved in the adolescents' decision‐making process by identifying the links among the foods consumed, the people they eat with and the places they eat in. Results emphasized the importance of the home environment and the continuing influence of parents on adolescents' eating behaviour despite the greater independence related to this stage of the life cycle. A proportion of the sample was found to have recognized the need to change their eating behaviour in order to lose weight, because of their sporting commitments or to improve their health. Recommendations from this study include the need for the various agencies involved in the promotion of balanced dietary behaviour to attend to the link among adult, family and adolescent, and the need for greater progress in enabling consumers to translate the theory of nutritional education into practice.

Protein‐leverage in Mice: The Geometry of Macronutrient Balancing and Consequences for Fat Deposition

The Protein-Leverage Hypothesis proposes that humans regulate their intake of macronutrients and that protein intake is prioritized over fat and carbohydrate intake, causing excess energy ingestion when diets contain low %protein. Here we test in a model animal, the mouse: (i) the extent to which intakes of protein and carbohydrate are regulated; (ii) if protein intake has priority over carbohydrates so that unbalanced foods low in %protein leads to increased energy intake; and (iii) how such variations in energy intake are converted into growth and storage. We fed mice one of five isocaloric foods having different protein to carbohydrate composition, or a combination of two of these foods (N = 15). Nutrient intake and corresponding growth in lean body mass and lipid mass were measured. Data were analyzed using a geometric approach for analyzing intake of multiple nutrients. (i) Mice fed different combinations of complementary foods regulated their intake of protein and carbohydrate toward a relatively well-defined intake target. (ii) When mice were offered diets with fixed protein to carbohydrate ratio, they regulated the intake of protein more strongly than carbohydrate. This protein-leverage resulted in higher energy consumption when diets had lower %protein and led to increased lipid storage in mice fed the diet containing the lowest %protein. Although the protein-leverage in mice was less than what has been proposed for humans, energy intakes were clearly higher on diets containing low %protein. This result indicates that tight protein regulation can be responsible for excess energy ingestion and higher fat deposition when the diet contains low %protein.

Nutrient utilization by caterpillars of the generalist beet armyworm, Spodoptera exigua

Abstract Beet armyworm, Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae), caterpillars are destructive crop pests responsible for considerable annual economic losses. These generalist herbivores are challenged with a diversity of dietary choices that can impact their survival, development and fecundity. In the present study, dietary choices of S. exigua caterpillars, based on the protein to digestible carbohydrate (P : C) ratio of the food, and the impact of nutritionally unbalanced foods on caterpillar performance are assessed. In choice experiments, individual third‐instar caterpillars are offered simultaneously a P‐biased and a C‐biased food until pupation. Caterpillars feed nonrandomly and select a slightly P‐biased diet (22P : 20C). In no‐choice experiments, second instar caterpillars are reared until pupation on diets ranging in P : C ratio from extremely P‐ to extremely C‐biased. High mortality and delayed development are observed on the C‐rich, P‐poor diets, highlighting the potential deleterious effects of excess carbohydrates and the importance of protein for growth and development. Diet‐dependent differences in pupal weight or pupal lipid reserves are not observed. This contrasts with closely‐related Spodoptera species where pupal mass and lipid stores increase on C‐rich, P‐poor diets. On the extremely P‐biased diet, performance is similar to that of individuals reared on the self‐selected diet, suggesting that these caterpillars may efficiently be deaminating excess amino acids to generate carbon skeletons, which are shunted into lipid biosynthesis. Spodoptera exigua caterpillars exhibit flexible and efficient pre‐ingestive nutrient intake regulation and post‐ingestive utilization, allowing these generalist feeders to cope with the heterogeneous diets they may encounter.

Fast and Sweet: Nutritional Attributes of Television Food Advertisements With and Without Black Characters

This study describes a content analysis of food advertisements featured in television programming popular with children. Advertisements featuring no Black primary characters were compared on the basis of character and food attributes with ads featuring at least one Black primary character. Advertised foods were then analyzed for the compliance of their nutritional content with the federal government's recommended daily values (RDVs) of select nutrients. Analyses revealed notable differences between ads depicting Black characters and ads without Black characters. Compared with ads without Black characters, ads with Black characters were more likely to sell convenience foods, especially fast foods, yet less likely to feature overweight characters. Ads without Black characters, in contrast, were more likely to sell foods high in sugar. Overall there were few differences in the nutritional breakdown of foods advertised in ads with and without Black characters, mainly because both types of ads tended to sell nutritionally unbalanced foods. A 2,000-calorie diet of foods advertised in both types of ads would exceed RDVs of total fat, saturated fat, and sodium, yet fail to provide RDVs of fiber and certain vitamins and minerals.

Distinctive flavours improve foraging efficiency in the polyphagous grasshopper, Taeniopoda eques

We examined the effect of adding flavours to foods of varying nutritional content on the foraging behaviour of the generalist grasshopper Taeniopoda eques. Each grasshopper received three dishes of food containing either (1) the same nutritionally balanced diet to which distinct flavours had or had not been added; or (2) three nutritionally unbalanced diets (lacking protein, sterol or starch) to which distinct flavours had or had not been added. We found that on the balanced foods, individuals ate similar quantities of food from each dish, but on the unbalanced foods, individuals ate most food from the dish lacking sterol and least of the food lacking protein. The proportions eaten reached a stable level and maximized intake of protein and carbohydrate. Although added flavours had no impact on proportions eaten from the dishes containing balanced food, on the unbalanced foods, individuals attained the stable proportions from the different dishes earlier. Furthermore, addition of flavours in either (1) or (2) resulted in greater food intake overall. On incomplete foods, the addition of flavours resulted in the development of additional oocytes. Thus, addition of diverse flavours enabled the grasshoppers to forage more efficiently, resulting in improvements in performance. These results demonstrate the importance of learning in the foraging efficiency of T. eques.

Consumer concerns about nutritional attributes in a transition economy

In Bulgaria, transition from a centrally planned to a market-driven system brought a substantial decline in real incomes and increase in general level of food prices. Resulting increases in food expenditure shares in household budgets, coupled with traditional diet patterns high in fat, energy, sugar and sodium, could lead consumers to purchase inexpensive and nutritionally unbalanced foods and potentially increase the risk of the incidence of diet-related health problems. Using a consumer survey data collected in 1997 in Bulgaria, the purpose of this study was to examine the relationship between sociodemographic characteristics and consumer concerns about five salient nutritional attributes including fat, sodium, sugar, food energy, and protein. Household income, educational attainment level, gender, age and geographic locations were statistically significant in explaining the variations in nutritional concerns of Bulgarian consumers. The results provide a basis for the development of public nutrition policies and health education programs paying special attention to the particular needs of identified subgroups of the population in Bulgaria.

The selection of nutritionally balanced foods by Locusts migratoria: the interaction between food nutrients and added flavours

Abstract. To investigate the ability of insects to discriminate between nutritionally balanced and unbalanced foods, fifth‐instar nymphs of Locusta migratoria L. (Orthoptera: Acrididae) were given one of thirteen pairings of artificial foods differing only in their concentration of protein and carbohydrate. One food, containing a previously estimated optimum balance of these nutrients, was common to each pairing. The relative intake of this ‘target’ food increased on the more extreme pairings, i.e. the insects demonstrated increasingly strong preference for the balanced food when it was paired with unbalanced alternative foods. When distinctive non‐nutritional flavours (tannic acid and amygdalin) were added to one or both of the foods, the insects' intake of the unbalanced foods increased, particularly on high‐protein foods. It is suggested that learned associations were not involved in the observed patterns of selection and that the added flavours disrupted the chemosensory responses to nutrients used by the insects to differentiate foods in this context.

Selective egestion of lysine by locusts fed nutritionally unbalanced foods

The quantitative profile of amino acids egested by fifth-stadium Locusta migratoria fed artificial foods differing in protein and carbohydrate content was investigated. Locusts fed foods with high (21%) protein content and low (7%) carbohydrate content selectively egested a large amount of lysine compared with other amino acids, despite its presence in the food at relatively low levels. Previous work has shown that lysine plays an important role in inhibiting feeding in protein-satiated locusts. It is suggested that this selective removal of lysine by locusts fed foods containing a relative excess of protein may counter the inhibition of feeding, thus enabling them to meet their requirements for other, limiting, nutrients.

The geometry of compensatory feeding in the locust

Abstract. A framework is presented for the study of feeding behaviour in the context of the multiple nutrient requirements of animals. Each nutrient required is represented by a single axis in a multi-dimensional plot. At any time the tissues will require a particular quantity and mix of nutrients. This ideal point is termed the 'nutritional target'. Meeting it involves the regulation of feeding behaviour and processing of ingested food. The ideal mix and quantity of nutrients that needs to be ingested to achieve the nutritional target is termed the 'intake target'. When fed a single food with a fixed proportion of nutrients, an animal is effectively restricted to a 'rail' in the nutritional space. Depending on this rail's slope, the intake target may not be achievable, in which case the animal should reach some optimal point of compromise on the rail. Considered together, the points of best compromise for a range of different rails will form an array on the plane, the shape and position of which, relative to the intake target, reveal the functional rule expressed by the physiological controlling mechanisms. Such concepts were investigated experimentally using locust, Locusta migratoria L., nymphs. Insects were given one of 25 artificial foods, containing one of five levels each of protein and digestible carbohydrate, and intake and growth were recorded across the fifth stadium. Two-dimensional plots of nutrient intake and growth were used to estimate the position of the intake and nutritional targets. On the basis of the array of intakes and estimates of the position of targets it was possible to test hypotheses about the functional rules employed by locusts to regulate their intake of nutrients. Both protein and carbohydrate intake were regulated equally efficiently. Locusts appeared to eat a given food such that they reached the geometrically closest point on their nutritional rail to the intake target ('closest distance optimization'). They 'jumped rails' by differentially utilizing ingested food and were thereby able to reach the growth component of the nutritional target (the 'growth target'). Only on extremely unbalanced foods did insects have a longer instar. The proximate mechanisms controlling the patterns are discussed. A simple, model animal is generated which is capable of making these sophisticated behavioural decisions without requiring a complex, central command centre.