Effects of total energy and individual nutrient intakes on energy balance.
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Animals↗
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Update on antiobesity drugs.
The Society for Medicines Research organized a one-day meeting on antiobesity drugs on March 26, 1998, in London. Current environmental risks for obesity include an increase in the proportion of fat consumption--especially an increase in the fat-to-carbohydrate ratio--and an increase in a sedentary life-style without an appropriate lowering in food intake. Energy balance plays a pivotal role of in the control of body stores. Knowing the mechanisms of the control of energy intake and energy expenditure provides explanations for the incidence of obesity and also possible sites for drug intervention. The genetic basis for obesity is complex, with the probability of a number of interacting genes being involved (polygenic inheritance). Each of the main components of the energy balance relationship has a distinct genetic basis. The ob gene was first identified in 1994 by Friedman, and its product is leptin, which may well be a potential target for obesity treatment. Speakers at the meeting highlighted various targets that hold promise in developing pharmacological treatments for obesity: increasing the activity of satiety factors (CCK-8, GPL-1, ACTH, alphaMSH and 5-HT acting on 5-HT(2C) receptors); inhibiting orexigenic agents (NPY, MCH, galanin); targeting thermogenesis (beta(3)-adrenergic agonists and uncoupling proteins); targeting fat absorption; and targeting neuropeptides. Some of the compounds developed to act on these sites are now becoming available.
Journal Article↗
Whole-body protein turnover and nitrogen balance in young children at intakes of protein and energy in the region of maintenance.
Nitrogen balance and whole-body protein turnover were measured in children aged about one year taking diets which provided 1.7 or 0.7 g milk protein/kg/d at three levels of metabolizable energy, 80, 90 and 100 kcal/kg/d. All the children were in positive nitrogen balance at all levels of energy intake on 1.7 g protein/kg/d. Nitrogen equilibrium was maintained on 0.7 g protein/kg/d when the energy intake exceeded 90 kcal/kg/d, but on 80 kcal/kg/d nitrogen balance was negative. Whole-body protein turnover was measured from the enrichment in urinary ammonia following a continuous infusion of 15N-glycine. The variation between individuals on the same diet was significantly greater than the variation within individuals at different levels of energy intake. For the group as a whole protein synthesis on 1.7 g protein/kg/d was 0.74, 0.75 and 0.87 g N/kg/d on 100, 90 and 80 kcal/kg/d respectively; whereas on 0.7 g protein/kg/d it was 0.37, 0.38 and 0.40 g N/kg/d. These results show that over this range of intakes protein synthesis decreased as dietary protein fell, but tended to increase as energy intake fell.
Ammonia↗
Associations between leptin gene polymorphisms and production, live weight, energy balance, feed intake, and fertility in Holstein heifers.
Leptin is a 16-kDa protein synthesized by adipose tissue and is involved in regulation of feed intake, energy balance, fertility, and immune functions. Since evidence of a genetic correlation between start of luteal activity and energy balance, milk yield, and live weights is present, we investigated the association of genetic differences in the bovine leptin gene with these traits. Between 1990 and 1997, a total of 613 Holstein-Friesian heifers of two genetic groups with known pedigree were followed from parturition until d 105 of lactation. During the first 15 wk of lactation live weight, feed intake, and milk yield were measured for 565 cows. The start of luteal activity was set at the first day with a progesterone concentration higher than 3 ng/ml. In addition to the interval between calving and start of luteal activity, analyses were performed for average milk yield, percentage fat, protein, and lactose in milk, dry matter intake, feed intake, energy balance, and live weight over the first 15 wk of lactation. All 613 cows were genotyped for two restricted fragment length polymorphisms and for the BM1500 microsatellite, all located at the leptin gene locus. Significances of the genotype effects were estimated using the approximated F-statistic provided by ASREML. Fixed effects were year-season, genetic group, and a quadratic polynomial for age at calving. Animal was fitted as a random effect including the additive relationship between animals to account for background genes. Firstly, each genotype effect was fitted in turn, and secondly the other restriction fragment length polymorphisms were fitted as a cofactor to take into account effects of linkage disequilibrium. Thirdly, sire x genotype interaction was investigated. Heifers with the RFLP1-AB genotype produce 1.32 kg/d more milk and consume 0.73 kg/d more food compared with the RFLP1-AA genotype. No effects were found for start of luteal activity. When linkage disequilibrium with the other markers was taken into account and DMI was included as fixed effect in the model a 0.96 kg/d higher milk yield was still found. Assuming that no pleiotropic effects on traits such as immunity and milk production in later lactations exist, future breeding programs favoring the RFLP1 B-allele can yield a higher milk production without negatively affecting energy balance and fertility. The prospects are good because in this study the frequency of the RFLP1 AB- and BB-genotypes were only 18.5 and 0.2%, respectively.
Animals↗
Weight gain in gonadectomized normal and lipoprotein lipase-deficient male domestic cats results from increased food intake and not decreased energy expenditure.
Gonadectomy predisposes domestic cats to undesired body weight gain and obesity. The disturbance responsible for this disregulation of energy balance has not been clearly identified. Energy intake and expenditure, body composition and plasma concentrations of leptin, insulin, glucose and triacylglycerol were determined during a 36-wk period in adult male (2-5 y) gonadectomized (n = 8) and intact (n = 8) normal cats and gonadectomized (n = 8) and intact (n = 8) lipoprotein lipase (LPL)-deficient cats. Cats were housed individually in temperature- and light-controlled rooms and continuously provided a commercial dry-type diet. In normal and LPL-deficient cats, body weight increased (P < 0.05) after gonadectomy by 27 to 29%, mostly as a result of fat accretion. There was a rapid increase (P < 0.05) in food intake of approximately 12% after gonadectomy of normal and LPL-deficient cats. The metabolic rate (kJ.kg(-1).d(-1)), determined in normal intact (319 +/- 20, n = 5) and gonadectomized (332 +/- 36, n = 5) cats, did not differ after gonadectomy. After gonadectomy, plasma concentrations of glucose and triacylglycerol did not change, whereas plasma insulin and leptin concentrations increased (P < 0.05), but not coincidentally with body weight gain. A stair-step increase in energy intake, and not decreased energy expenditure, appears to drive the weight gain associated with gonadectomy. Body fat mass appears to increase until the energy intake supports no further expansion. Adiposity signaling through insulin or leptin does not appear to mediate the energy intake effect. LPL deficiency did not preclude development of the overweight body condition. Therefore, gonadectomy-induced weight gain in cats is not a result of changed adipose LPL activity, as previously suggested.
Animals↗
Effects of amount and type of dietary fat on serum lipids, lipoproteins and apolipoproteins in man. A controlled 8-week trial.
We have studied whether a low-fat diet is as effective in lowering some risk factors for atherosclerosis as a diet rich in polyunsaturated fat (PUFA). During a 2.5 week control period, 60 volunteers were given a moderate-fat diet (MOD) providing 30% of the daily energy intake (energy %) in the form of fat, one-third of which was PUFA. For the next 5 weeks subjects were divided into 4 groups and received diets providing varying amounts of total fat and of PUFA: for group LO, 20 energy % PUFA; group HIPUF, 40 energy % fat and 19 energy % PUFA; and group HISAT, 40 energy % fat and 3 energy % PUFA. The diets contained the same amounts of cholesterol, phytosterols, oligosaccharides and other nutrients, known to affect serum lipid levels. All food was prepared daily and weighed out for each individual appropriate to his energy needs. Nutrient intakes were checked by 7-day records and by chemical analysis of double portions. On diet LO, total serum cholesterol concentration increased by 0.25 mmol/l while HDL cholesterol concentration did not change significantly. The HDL cholesterol/apoprotein-A1 ratio fell, and VLDL and LDL triglyceride centrations were elevated. On the HIPUF diet, total serum cholesterol concentration was not significantly lower, but HDL cholesterol concentration increased by 0.10 mmol/l. On the HISAT diet, total serum cholesterol concentration went up by 0.38 mmol/l; 0.12 mmol/l of this was due to HDL. LDL cholesterol/serum apoprotein-B ratios were unaffected by any of the diets. It was concluded that after 5 weeks, the influence of a low-fat, high-carbohydrate diet on the concentrations of serum lipoproteins was less favourable than that of moderate- or high-fat diets rich in polyunsaturated fatty acids.
Adolescent↗
Energy metabolism of growing rats. 1. Effect of energy and protein intake on energy retention.
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Animals↗
Alcohol consumption and metabolic syndrome: does the type of beverage matter?
OBJECTIVE: To examine the association between total and beverage-specific alcohol consumption and the prevalence odds of metabolic syndrome (MS). RESEARCH METHODS AND PROCEDURES: Using a cross-sectional design, we studied 4510 white participants of the National Heart, Lung, and Blood Institute Family Heart Study. We used generalized estimating equations adjusting for age, education, risk group, smoking, physical activity, diabetes mellitus, coronary heart disease, energy intake, energy from fat, fruits, and vegetables, dietary cholesterol, dietary fiber, and use of multivitamins to estimate the prevalence odds of MS by alcohol intake. RESULTS: Compared with never-drinkers, multivariate odds ratios (95% confidence interval) for MS were 1.12 (0.85 to 1.49), 0.68 (0.36 to 1.28), 0.72 (0.50 to 1.03), 0.66 (0.44 to 0.99), and 0.80 (0.55 to 1.16) among men who were former drinkers and who were current drinkers of 0.1 to 2.5, 2.6 to 12.0, 12.1 to 24.0, and >24.0 g/d of alcohol, respectively (p for linear trend 0.018). Corresponding values for women were 0.86 (0.69 to 1.09), 0.80 (0.43 to 1.34), 0.47 (0.33 to 0.66), 0.47 (0.30 to 0.74), and 0.39 (0.21 to 0.74), respectively (p for trend < 0.0001). The reduced prevalence odds of MS was observed across all beverage types: compared with never-drinkers, multivariate adjusted odds ratios (95% confidence interval) of MS were 0.32 (0.14 to 0.73), 0.42 (0.23 to 0.77), 0.57 (0.30 to 1.09), and 0.56 (0.36 to 0.88) for subjects who consumed >7 drinks/wk of wine only, beer only, spirits only, and more than one type of beverage, respectively. DISCUSSION: Our data indicate that alcohol consumption is associated with a lower prevalence of MS irrespective of the type of beverage consumed. Prospective studies are needed to confirm these findings and to assess the influence of drinking patterns on the alcohol-MS association.
Adult↗
Validity of reported energy expenditure and reported intake of energy, protein, sodium and potassium in rheumatoid arthritis patients in a dietary intervention study.
OBJECTIVES: The aim of the study was to validate a diet history interview (DHI) method and a 3-day activity registration (AR) with biological markers. SUBJECTS AND STUDY DESIGN: The reported dietary intake of 33 rheumatoid arthritis patients (17 patients on a Mediterranean-type diet and 16 patients on a control diet) participating in a dietary intervention study was assessed using the DHI method. The total energy expenditure (TEE), estimated by a 3-day AR, was used to validate the energy intake (EI). For nine subjects the activity registration was also validated by means of the doubly labelled water (DLW) method. The excretion of nitrogen, sodium and potassium in 24-h urine samples was used to validate the intake of protein, sodium and potassium. RESULTS: There was no significant difference between the EI and the TEE estimated by the activity registration or between the intake of protein, sodium and potassium and their respective biological markers. However, in general, the AR underestimated the TEE compared to the DLW method. No significant differences were found between the subjects in the Mediterranean diet group and the control diet group regarding the relationship between the reported intakes and the biological markers. CONCLUSION: The DHI could capture the dietary intake fairly well, and the dietary assessment was not biased by the dietary intervention. The AR showed a bias towards underestimation when compared to the DLW method. This illustrates the importance of valid biological markers.
Arthritis, Rheumatoid↗
Nutritional treatment of hemodialysis and peritoneal dialysis patients.
The success of hemodialysis and peritoneal dialysis therapy is essentially dependent on adequate nutrition. Malnutrition represents one of the main factors in morbidity and mortality of dialysis patients. The main causes of malnutrition are insufficient energy intake, insufficient protein supply, loss of amino acids by dialysis, the uremic state of metabolism, catabolic stress of underlying diseases, and endocrinological disorders. For successful long-term chronic dialysis therapy, it is very important that patients be in an anabolic nutritional state when entering the dialysis program. In this paper, the nutritional needs of dialysis and peritoneal dialysis patients (fluid restriction, protein intake, energy supply, electrolyte balance, vitamin intake) are discussed to prevent the catabolic state.
Dietary Proteins↗
Leptin signaling, adiposity, and energy balance.
A chronic minor imbalance between energy intake and energy expenditure may lead to obesity. Both lean and obese subjects eventually reach energy balance and their body weight regulation implies that the adipose tissue mass is "sensed", leading to appropriate responses of energy intake and energy expenditure. The cloning of the ob gene and the identification of its encoded protein, leptin, have provided a system signaling the amount of adipose energy stores to the brain. Leptin, a hormone secreted by fat cells, acts in rodents via hypothalamic receptors to inhibit feeding and increase thermogenesis. A feedback regulatory loop with three distinct steps has been identified: (1) a sensor (leptin production by adipose cells) monitors the size of the adipose tissue mass; (2) hypothalamic centers receive and integrate the intensity of the leptin signal through leptin receptors (LRb); (3) effector systems, including the sympathetic nervous system, control the two main determinants of energy balance-energy intake and energy expenditure. While this feedback regulatory loop is well established in rodents, there are many unsolved questions about its applicability to body weight regulation in humans. The rate of leptin production is related to adiposity, but a large portion of the interindividual variability in plasma leptin concentration is independent of body fatness. Gender is an important factor determining plasma leptin, with women having markedly higher leptin concentrations than men for any given degree of fat mass. The ob mRNA expression is also upregulated by glucocorticoids, whereas stimulation of the sympathetic nervous system results in its inhibition. Furthermore, leptin is not a satiety factor in humans because changes in food intake do not induce short-term increases in plasma leptin levels. After its binding to LRb in the hypothalamus, leptin stimulates a specific signaling cascade that results in the inhibition of several orexigenic neuropeptides, while stimulating several anorexigenic peptides. The orexigenic neuropeptides that are downregulated by leptin are NPY (neuropeptide Y), MCH (melanin-concentrating hormone), orexins, and AGRP (agouti-related peptide). The anorexigenic neuropeptides that are upregulated by leptin are alpha-MSH (alpha-melanocyte-stimulating hormone), which acts on MC4R (melanocortin-4 receptor); CART (cocaine and amphetamine-regulated transcript); and CRH (corticotropin-releasing-hormone). Obese humans have high plasma leptin concentrations related to the size of adipose tissue, but this elevated leptin signal does not induce the expected responses (i.e., a reduction in food intake and an increase in energy expenditure). This suggests that obese humans are resistant to the effects of endogenous leptin. This resistance is also shown by the lack of effect of exogenous leptin administration to induce weight loss in obese patients. The mechanisms that may account for leptin resistance in human obesity include a limitation of the blood-brain-barrier transport system for leptin and an inhibition of the leptin signaling pathways in leptin-responsive hypothalamic neurons. During periods of energy deficit, the fall in leptin plasma levels exceeds the rate at which fat stores are decreased. Reduction of the leptin signal induces several neuroendocrine responses that tend to limit weight loss, such as hunger, food-seeking behavior, and suppression of plasma thyroid hormone levels. Conversely, it is unlikely that leptin has evolved to prevent obesity when plenty of palatable foods are available because the elevated plasma leptin levels resulting from the increased adipose tissue mass do not prevent the development of obesity. In conclusion, in humans, the leptin signaling system appears to be mainly involved in maintenance of adequate energy stores for survival during periods of energy deficit. Its role in the etiology of human obesity is only demonstrated in the very rare situations of absence of the leptin signal (mutations of the leptin gene or of the leptin receptor gene), which produces an internal perception of starvation and results in a chronic stimulation of excessive food intake.
Adipose Tissue↗
Energy expenditure and requirements in aging humans.
Although physical activity is frequently recommended for the elderly individual, its influence on energy intake and energy expenditure is unclear. The use of indirect calorimetry techniques and stable isotopes make it possible to examine the effects of physical activity on total daily energy expenditure and its components. In this review, the influence of physical activity on adaptive changes in energy intake, daily energy expenditure, resting metabolic rate and the energy expenditure of physical activity during nonexercising time was examined. Recent findings show that moderate physical activity can increase resting metabolic rate and energy intake in the elderly. Vigorous exercise, however, did not increase total daily energy expenditure because of a compensatory decline in physical activity during nonexercising time. These findings should prompt investigators to re-examine the influence of different levels of endurance exercise on total daily energy expenditure in an attempt to maximize the energy expending properties of physical exercise in older persons. A second objective was to examine the current status of methodology to predict energy requirements in older persons. Current recommendations for energy lack specificity and have not considered the influence of physical activity and body composition. Energy needs of older persons need to be re-examined based on the measurement of total daily energy expenditure. It will then be important to identify biological markers of total daily energy expenditure that take into account the variation in physical activity and body composition.
Aged↗
Quantitative review of the effects of environmental temperature on food intake, egg output and energy balance in laying pullets.
1. Data from 30 published experiments have been analysed to examine the relationships between environmental temperature and the long-term, adapted responses of laying pullets, measured as metabolisable energy intake, egg output and body weight change. Heat production was also estimated indirectly from the other three variables. 2. The majority of experiments employed White Leghorns, but there were 8 large trials in which brown crossbred pullets had been compared directly with White Leghorns. These trials were used to estimate differences in energy intake and heat output between brown and white birds. 3. A total of over 26,000 birds was involved in the analysis. Individual trials varied in scale from 9 birds to 2,280 birds per treatment and in duration from 8 to 61 weeks. The constant temperatures investigated ranged from 10 degrees C to 34 degrees C, but there were no data for brown pullets beyond 30 degrees C. 4. The relationship between temperature and metabolisable energy intake is curvilinear, with food intake declining more steeply as ambient temperature approaches body temperature. Adapted heat production per bird is also a curvilinear function of temperature, tending towards a value of zero when extrapolated to the point at which ambient temperature equals normal body temperature. However no satisfactory data are available for fully adapted responses in the range 34 to 42 degrees C because egg production declines continuously when these temperatures are maintained for long periods. 5. When energy intake and heat output are expressed as functions of metabolic body size (kg 0.75) they can be represented as linear functions of temperature within the range 15 to 30 degrees C, but the slope must change outside this range. 6. It is calculated that the energy available for production is at a maximum at 23 degrees C for brown birds and at 24 degrees C for White Leghorns. Gross energetic efficiency is at a maximum at 30 degrees C, but egg output is reduced at this temperature. The optimum operating temperature for laying houses will depend upon the local cost of modifying ambient temperature and on the cost of supplying diets of appropriate protein content.
Animals↗
Competitive foods increase the intake of energy and decrease the intake of certain nutrients by adolescents consuming school lunch.
OBJECTIVE: To determine the influence of competitive foods on energy and nutrient intakes of adolescents participating in a school lunch program. DESIGN: Weighed plate waste data were used to assess the energy and nutrient consumption from school lunch menus items and competitive food items chosen and consumed by adolescents. The two test groups were students choosing competitive foods and those choosing no competitive foods. SUBJECTS/SETTING: Participants were sixth-grade students aged 11 to 13 years purchasing lunch in three public middle school cafeterias in Franklin County, KY (n=493 for no competitive foods and n=250 for competitive foods). The data were collected over 24 days in 2 school years. STATISTICAL ANALYSES PERFORMED: Significant differences between the competitive foods and no competitive foods groups were determined using frequency and analysis of variance procedures. RESULTS: The data indicate that sixth-grade adolescents consumed energy and other nutrients (except iron) at significantly lower than recommended levels; one third of students purchasing school lunch also purchased competitive food items; competitive foods purchasers reduced their school lunch servings, portion weight and/or item selection and increased school lunch item plate waste, resulting in lower intakes of energy (400 kcal vs 530 kcal for no competitive foods), calcium (300 mg vs 362 mg for no competitive foods), and vitamin A (77 retinol equivalents vs 113 retinol equivalents for no competitive foods) from the school lunch; and competitive foods supplied more than one third of total energy for the meal. CONCLUSIONS: These data will enable school cafeteria planners to develop menus that include more nutritious foods, snacks, and drinks instead of the currently available competitive foods.
Adolescent↗
Energy balance in cross-country skiers: a study using doubly labeled water.
Energy intake covering energy expenditure is essential for performance as well as for health aspects in endurance athletes. This study was performed to determine the energy needs for elite cross country skiers during a week of training and to demonstrate whether energy balance could be maintained. Energy intake was calculated from weighed dietary records and doubly labeled water was used to simultaneously measure energy turnover. Average daily energy intake ranged from 15.7 to 20.4 MJ.d-1 in the females and from 25.7 to 36.0 MJ.d-1 in the males. This correlated well with the data for average daily energy turnover (r = 0.96; P = 0.0001) that ranged from 15.1 to 20.2 MJ.d-1 and from 25.4 to 34.9 MJ.d-1, in females and males, respectively. The mean difference being 0.1 (+/- 1.9) MJ.d-1. The close match between energy intake and energy expenditure has not previously been shown in athletes at these high levels of energy turnover. However, if energy intake over separate 24-h periods was compared with corresponding data for training, no significant relationship was found. This indicates that the athletes were not in energy balance during shorter periods. Furthermore, the validity of theoretical calculations of energy turnover, in highly trained subjects, derived from multiples of estimated BMR, is questioned.
Adult↗
Clinical trial of home available, mixed diets versus a lactose-free, soy-protein formula for the dietary management of acute childhood diarrhea.
A randomized clinical trial was completed to study the severity, duration, and nutritional outcome of acute diarrhea in 85 Peruvian children between 5 and 24 months of age who received a soy-protein-isolate, lactose-free formula (group SF) or one of two mixtures of home-available foods, all in amounts up to 110 kcal/kg of body weight/day. The mixed diets contained either wheat flour, pea flour, carrot flour, sucrose, and vegetable oil (group WP) or potato flour, dried whole milk, carrot flour, sucrose, and oil (group PM). The characteristics of the children in each group were generally similar initially. There were no differences in treatment failure rate by diet group. Fecal outputs were similar in all groups during the first day of treatment, averaging 60 to 65 g/kg/day. However, stool outputs were greater for the PM group than for other groups on days 3 and 4, and were less for the SF group than the other groups on days 5 and 6. The estimated median durations of diarrhea in the WP group (52 h) and PM group (53 h) were significantly less than in the SF group (154 h, p = 0.005). Energy intakes, energy absorption, and nitrogen retention (% of intake) were generally similar in all dietary groups, although there were minor differences in the absorption of specific macronutrients. Children in all groups gained weight during hospitalization, and there were no significant differences by diet group in the change in anthropometric status during treatment. We conclude that these locally available, low-cost staple food mixtures offer a safe and nutritionally adequate alternative to a commercially produced lactose-free formula for the dietary management of young children with acute diarrhea in this setting.
Acute Disease↗
Energy turnover at the Race Across AMerica (RAAM) - a case report.
We report about energy intake and energy expenditure in an official finisher of the Race Across AMerica (RAAM) in 2003. Energy intake from nutrition was continuously recorded. Energy expenditure was measured by continuous heart rate recording with a portable heart rate monitor POLAR S710 to estimate energy expenditure during physical activity. Our athlete (33 years, 179 cm, 73 kg, VO (2)max 60 ml . min (-1) . kg (-1), lactate threshold at 77%VO (2)max) finished the 4701-km cycling race with altitude differences amounting to 25,826 meters in 9 days 16 hours and 45 minutes in 4th place. He completed 470+/-72.9 km (372-541 km) per day with 2,582+/-1,576 (683-5,047) meters of altitude. During the whole race, he expended a total energy of 179,650 kcal with 17,965+/-2165 (15,100 - 23,280) kcal per day. Total energy intake was 96,124 kcal with an average of 9,612+/-1,500 (7,513-12,735) kcal per day. Of total ingested calories, 75.2% derived from carbohydrates, 16.2% from fat, and 8.6% from protein. He ingested an energy of 9,612+/-1,550 (7,513 - 12,735) kcal daily, consisting of 1,814+/-310 (1,336 - 2,354) g of carbohydrates, 172+/-47 (88-251) g of fat, and 207+/-52 (128-286) g of protein. The average daily energy deficiency amounted to 8,352+/-2,523 (4,425-13,631) kcal. A total deficiency of 83,526 kcal resulted after the race while the athlete lost 5 kg of body weight. These results provide data about energy intake and energy expenditure in the RAAM for future athletes, nutritionists and coaches. Further investigation should be performed in order to determine whether either muscle mass or body fat will be lost in extreme endurance cycling.
Adult↗
[Energy and nutrient supply during childhood. I. Food intake and energy supply (author's transl)].
From 1965--1975 the food intake and energy supply of children aged 2--14 years in families of different social classes were studied with the precise weighing method. The individual child was surveyed on an average of 21--42 successive days. Energy intake increased from 1450 for boys aged 2--3 years to 2600 kcal/day for boys aged 12--14 years, girls of the same age had an energy intake between 1300 to 2400 kcal/day. The differences between boys and girls regarding energy intake, absolute and per kg body weight, are shown. Our results of the energy intake are representative for children of the same age groups in other highly industrialized countries. The energy intake of preschool-children was equally distributed among 4 meals per day, whereas in school-children it was distributed among 5 meals with different energy contents. 35--50% of the energy supply is of animal origin, 60--65% of vegetable origin. The contribution of different food groups to the energy supply and the differences in the intake of these food groups between pre-school-and school-children are demonstrated. For the individual child a survey period of 21--28 days is necessary to obtain its individual average energy intake with the maximum standard deviation. The significance of general averages for the energy supply of age groups regarding the individual child is discussed. The day to day variations of energy intake in children are shown. The significance of these variations for nutrition in health and disease is discussed.
Adolescent↗