Dietary recommendations for children and adolescents with diabetes†

Dietary advice for diabetes has changed significantly over the last ten years, the emphasis being on a total energy intake matched to individual requirements and on the physical as well as chemical structure of food and meals. It is recommended that energy intake is still distributed through the day as regular meals and snacks using a carbohydrate exchange system, but with 50% of dietary energy being derived from carbohydrate sources mainly in complex and unrefined form. This paper considers how far the dietary recommendations for adults can be applied to children.     

Determination of macronutrients,by chemical analysis,of home-prepared milk feeding bottles and their contribution to the energy and protein requirements of infants from high and low socioeconomic classes

OBJECTIVES: To determine the macronutrients composition of home-prepared milk feeding bottles, by chemical analysis, and assess their contribution to the energy and protein requirements of children under two years of age from high (HSE) and low (LSE) socioeconomic classes. METHODS: 72 samples were analyzed for energy density and protein, fat and carbohydrate content: 41 from the LSE group and 31 from the HSE group. The assessment of the percentages of the energy and protein requirements met by the consumption of the milk bottles was calculated as follows: the energy and protein per 100 mL obtained through chemical analysis were multiplied by the volume consumed at each feeding, then by the number of feedings per day, the results divided by the energy and protein requirements and multiplied by 100. Energy and protein requirements were those recommended by the FAO/WHO/UNU Committee and the Food and Nutrition Board. The children's weight-for-age index was assessed. RESULTS: Unmodified cow's milk was largely consumed by both groups. The addition of sugar and other ingredients to the milk was significantly higher in the LSE group. Moisture, protein and fat content were lower in the LSE group, whereas carbohydrate and energy content were higher. The percentages of energy and protein requirements provided by feeding bottles were higher in the LSE group. Children in the LSE group had lower z-scores for weight-for-age. CONCLUSIONS: Differences in the preparation practices led to differences in the chemical results. The feeding bottles in the LSE group were high in energy, due to the addition of sugar and cereals to the milk in the bottle. The milk feeding bottles were an important weaning food providing more than 50% and 100% of the children's energy and protein requirements, respectively. The children's weight-for-age index was within the normal limits.     

The thiamine status of adult humans depends on carbohydrate intake

Thiamine requirements for humans are generally expressed as absolute values per day (mg/d) or in relation to total caloric intake. Limited data are available on the relation between thiamine requirements and the intake of carbohydrates. This study was performed to investigate the influence of stepwise increases of carbohydrate intake on the status of thiamine in healthy volunteers under isocaloric conditions. During an adaptation phase of four days, the carbohydrate intake of twelve healthy volunteers (6 male, 6 female) was 55% of total energy intake. During the subsequent intervention periods, carbohydrate intake was increased to 65% of total energy for four days and to 75% for another four days. Thiamine intake, total energy intake, and physical activity were kept constant throughout the study. HPLC analysis was used to measure thiamine in plasma, urine and feces. Erythrocyte transketolase activity (ETK) was determined enzymatically. During the intervention periods thiamine decreased significantly (p < 0.05) in plasma (from 19.3 +/- 3.3 to 16.4 +/- 4.0 nmol/l) as well as in urine (from 72 +/- 56 to 58 +/- 21 mumol/mol creatinine). ETK and feces content of thiamine remained unchanged. An increase of dietary carbohydrate intake from 55% to 65% and 75%, respectively, of total caloric intake for four days per period at isocaloric conditions causes a decrease of plasma and urine levels of thiamine without affecting enzyme activities.     

Protein requirements for endurance athletes

Acute endurance exercise results in the oxidation of several amino acids. The total amount of amino acid oxidation during endurance exercise amounts to only 1-6% of the total energy cost of exercise. The branched chain amino acid, leucine, has been most often studied in relation to endurance exercise. Leucine is oxidized by the enzyme, branched-chain oxo-acid dehydrogenase (BCOAD). BCOAD is relatively inactive at rest ( approximately 4-7%) and is activated at the onset of exercise by dephosphorylation (to about 25%). After a period of endurance exercise training, the activation of BCOAD and amino acid oxidation are attenuated, however the total amount of BCOAD enzyme is up-regulated. A low energy and/or carbohydrate intake will increase amino acid oxidation and total protein requirements. With adequate energy and carbohydrate intake, low to moderate intensity endurance activity has little impact on dietary protein requirements and 1.0 gPRO/kg/d is sufficient. The only situation where dietary protein requirements exceed those for relatively sedentary individuals is in top sport athletes where the maximal requirement is approximately 1.6 gPRO/kg/d. Although most endurance athletes get enough protein to support any increased requirements, those with low energy or carbohydrate intakes may require nutritional advice to optimize dietary protein intake.     

Determination of Macronutrients,by Chemical Analysis,of Home-Prepared Milk Feeding Bottles and their Contribution to the Energy and Protein Requirements of Infants from High and Low Socioeconomic Classes

Objectives: To determine the macronutrients composition of home-prepared milk feeding bottles, by chemical analysis, and assess their contribution to the energy and protein requirements of children under two years of age from high (HSE) and low (LSE) socioeconomic classes.

Methods: 72 samples were analyzed for energy density and protein, fat and carbohydrate content: 41 from the LSE group and 31 from the HSE group. The assessment of the percentages of the energy and protein requirements met by the consumption of the milk bottles was calculated as follows: the energy and protein per 100 mL obtained through chemical analysis were multiplied by the volume consumed at each feeding, then by the number of feedings per day, the results divided by the energy and protein requirements and multiplied by 100. Energy and protein requirements were those recommended by the FAO/WHO/UNU Committee and the Food and Nutrition Board. The children’s weight-for-age index was assessed.

Results: Unmodified cow’s milk was largely consumed by both groups. The addition of sugar and other ingredients to the milk was significantly higher in the LSE group. Moisture, protein and fat content were lower in the LSE group, whereas carbohydrate and energy content were higher. The percentages of energy and protein requirements provided by feeding bottles were higher in the LSE group. Children in the LSE group had lower z-scores for weight-for-age.

Conclusions: Differences in the preparation practices led to differences in the chemical results. The feeding bottles in the LSE group were high in energy, due to the addition of sugar and cereals to the milk in the bottle. The milk feeding bottles were an important weaning food providing more than 50% and 100% of the children’s energy and protein requirements, respectively. The children’s weight-for-age index was within the normal limits.     

Effects of inulin on faecal bifidobacteria in human subjects

A controlled study with eight healthy free-living subjects was carried out, in which energy intake was adjusted to the individual energy requirements. On administration of inulin, blood lipids, the faecal microflora, short-chain fatty acids and accompanying gastrointestinal symptoms were characterized in order to investigate the long-term effect of inulin. During the run-in phase (8 d), subjects received a typical Western diet providing 45% energy as fat and 40% energy as carbohydrate. Subsequently, the subjects consumed a fat-reduced diet which provided 30% energy as fat and 55% energy as carbohydrate for a period of 64 d using inulin as a fat replacer. The amounts of inulin consumed by the subjects (up to 34 g/d) were based on individual energy requirements with the aim to keep the diet isoenergetic with that used in the run-in period. To assess the effects of inulin administration, a control study (run-in and intervention) was carried out in which subjects consumed the same diet but devoid of inulin during the whole course of the study. To investigate the effect of inulin on faecal flora composition total bacteria and bifidobacteria in the faeces were enumerated by in situ hybridization with 16S rRNA targeted oligonucleotide probes. Inulin significantly increased bifidobacteria from 9.8 to 11.0 log10/g dry faeces and caused a moderate increase in gastrointestinal symptoms such as flatulence and bloatedness, whereas blood lipids and short-chain fatty acids remained essentially unaffected.     

Relation of body energetic status to dietary self-selection in Sprague-Dawley rats

Self-selection from carbohydrate, protein and fat sources including essential micronutrients was studied in male Sprague-Dawley rats that were 4 weeks of age at the beginning of the experiment. During the experimental period of 14 days, the intake of carbohydrate and fat was quite constant, whereas that of protein increased gradually. The mean intake of carbohydrate, protein, and fat was 31.1 +/- 3.5%, 56.1 +/- 4.6%, and 12.8 +/- 2.8% of the total energy intake, respectively. Animals fed on a mixed diet consisting of high sucrose, consumed 65.1% of their daily energy as carbohydrate, 17.6% as protein, and 17.3% as fat. Total energy intake and body weight gain were not significantly different between the rats on self-selection and those fed on the mixed diet. These results indicate that young rats on dietary self-selection were able to gain body weight comparable to that of rats fed on the mixed diet. Body energetic status affected self-selection patterns. In rats fasted for 5 days or fed on a protein-free diet for 21 days, fat intake increased, but protein intake decreased. On the other hand, fat intake decreased in animals given a sucrose diet higher in energy content than the stock diet; these animals exhibited increased accumulation of body energy. These results indicate that dietary self-selection is closely related to nutritional and physiological body requirements.     

Tandem Breastfeeding: A Descriptive Analysis of the Nutritional Value of Milk When Feeding a Younger and Older Child

Breastfeeding is a gold standard of feeding of newborns and infants. Tandem breastfeeding (TBF) is feeding two children of different ages at the same time. The knowledge about the composition of human milk in prolonged lactation is still scarce. Milk from tandem breastfeeding women and after weaning was examined. Milk samples were collected from 13 TBF mothers. A 24-h milk collection was done. Analyses of fat, protein, carbohydrate and energy content were performed using MIRIS. Sociodemographic characteristics of TBF mothers was done. Higher fat content, energy value and total protein concentration was found in TBFM milk during tandem breastfeeding, than in milk after weaning the older child. The carbohydrate content remained stable. The composition of breastmilk, in terms of macronutrients, changes after weaning, taking into account the nutritional requirements of the younger child. The milk of nursing mothers in tandem did not show diurnal variability in individual components. These findings suggest an adaptive role of human milk to nutrient requirements of newborn and older children. The results may support the promotion of long breastfeeding, including tandem breastfeeding.     

Dietary influences on carbohydrases and small intestinal starch hydrolysis capacity in ruminants.

Data describing the influence of diet composition and intake on amylolytic and disaccharidase activities in the ruminant small intestine are reviewed. Changing dietary components from forage to grain increased pancreatic alpha-amylase activities in most studies; however, when metabolizable energy intake was equalized, concentrations of alpha-amylase in the pancreas and the total quantities in the small intestinal lumen were greater in forage-fed than in grain-fed animals. Concentration of pancreatic alpha-amylase increased with dietary energy intake. Changing diet composition or metabolizable energy intake exerted a small effect on intestinal disaccharidase activities, with hydrolytic capacity altered principally through changes in intestinal length. Other studies suggest a small contribution of intestinal disappearance of carbohydrates to net portal appearance of glucose. The fate of large portions of intestinal carbohydrate disappearance have not been adequately defined. For the importance of intestinal carbohydrate supply to be understood, the quantity of carbohydrate undergoing both enzymatic hydrolysis and absorption must be determined.     

Food intake and energy expenditure of Indian troops in training.

1. Food intake and energy expenditure were determined on 500 soldiers drawn from infantry, artillery and engineer units of the Indian army, for 3 months during winter. 2. The units were located in two different regions of India at altitudes varying from sea level to 2300 m. 3. The energy requirements were assessed from the actual food intake as well as from energy expenditure and from the changes in body-weight and skinfold thickness. 4. The nutritional adequacy of the diet was assessed from clinical examination and changes in blood haemoglobin concentration. 5. The mean energy expenditure was found to be 15-39 MJ (3679 kcal) and on this basis the energy requirements was 16-61 MJ (3970 kcal); energy intake was found to be 16-47 MJ (3936 kcal). 6. The energy contributed by protein, fat and carbohydrate was 0-115, 0-240 and 0-645 of the total intake respectively. 7. There was no significant change in body-weight, blood haemoglobin level and skinfold thickness on this mean daily intake.     

Nutritional requirements based on substrate fluxes in trauma

The metabolic requirements of the severely injured patient dictate the appropriate nutritional support. There is an increase in energy expenditure by the injured person that is associated with increased protein catabolism. The injured patient also utilizes increased amounts of carbohydrate and lipid. The proportions of carbohydrate and lipid utilized appear to depend on the relative amount of calories provided to the injured subject. Measurement of energy expenditure in patients receiving glucose indicates that at most 60% of the expired CO₂ is derived from glucose oxidation. Because protein oxidation contributes approximately 20% of the expired CO₂, lipid oxidation contributes the remaining 20% of the expired CO₂. Therefore, the injured patient should be provided with sufficient calories in the proportion 60% glucose, 20% protein, and 20% lipid.     

Diet and physical performance

This paper provides a historical summary of military nutrition research into the role of diet for sustaining soldier physical performance. Studies of underfeeding document that physical performance is preserved during several days of underfeeding provided sufficient carbohydrate and minerals are consumed to minimize the diuresis associated with semi-starvation diets and serial intake of carbohydrate is available to support metabolism during prolonged work. The Military Recommended Dietary Allowances, AR 40-25, currently recommends that when restricted rations are required, that the ration contain at least 1,100-1,500 kcal, 50-70 g of protein, and a minimum of 100 g of carbohydrate on a daily basis. This low energy diet, however, is not recommended for subsistence for longer than 10 consecutive days. Dietary carbohydrate intakes of approximately 300-400 g will more closely match the quantity of carbohydrate oxidized to meet daily energy requirements during field operations. Research into the potential advantages of dietary supplements has generally not proved advantageous when compared to eating a well balanced diet. Future investigations of the role of diet for sustaining soldier health and performance should be directed toward a better understanding of the influence of energy intake and macro-nutrient composition for preserving lean body mass, reducing susceptibility to illness and injury and enhancing recovery during and after sustained operations.     

Macronutrient disposal during controlled overfeeding with glucose, fructose, sucrose, or fat in lean and obese women

BACKGROUND: Previous short-term studies (< or =6 h) showed differences in energy expenditure (EE) and macronutrient oxidation in response to overfeeding with different types of dietary carbohydrate. This finding could have implications for obesity. OBJECTIVE: We used 96-h continuous whole-body calorimetry in 8 lean and 5 obese women to assess metabolic disposal (energy dissipation and glycogen or fat storage) of a controlled excess of dietary energy supplied as different carbohydrate sources or as fat. DESIGN: Five dietary treatments were applied in random order: energy balance (control) and overfeeding by 50% of energy requirements with fat (O(fat)) or predominantly with glucose, fructose, or sucrose (O(cho)). Macronutrient oxidation rates were assessed from nonprotein gaseous exchanges. Net macronutrient balances were calculated as cumulative differences between intake and oxidation. RESULTS: Increased EE in response to overfeeding dissipated 7.9% of the energy excess with a variation in EE of <1.7% across overfeeding treatments (NS). EE during the O(fat) treatment significantly exceeded that during the control treatment in the lean but not in the obese women. There were no significant differences between lean and obese women in macronutrient oxidation or balances, so data were pooled. O(cho) induced glycogen storage on day 1 ( approximately 100 g) but thereafter progressively stimulated carbohydrate oxidation so that balance was reached on days 3 and 4. Fat oxidation was proportionately suppressed. Of the excess carbohydrate, 74% was oxidized; there were no significant differences between the various O(cho) treatments. O(fat) stimulated fat oxidation by 18% and suppressed carbohydrate oxidation. On average, 12% of the excess energy was stored as glycogen and 88% as fat; there was no significant difference between overfeeding treatments. CONCLUSION: There was no significant difference in fat balance during controlled overfeeding with fat, fructose, glucose, or sucrose.     

Can nutrition limit exercise-induced immunodepression?

Prolonged exercise and heavy training are associated with depressed immune cell function. To maintain immune function, athletes should eat a well-balanced diet sufficient to meet their energy, carbohydrate, protein, and micronutrient requirements. Consuming carbohydrate during prolonged strenuous exercise attenuates rises in stress hormones and appears to limit the degree of exercise-induced immune depression. Recent evidence suggests that antioxidant vitamin supplementation may also reduce exercise stress and impairment of leukocyte functions. Further research is needed to evaluate the effects of other antioxidants and dietary immunostimulants such as probiotics and echinacea on exercise-induced immune impairment.     

中国9省(区)2000－2011年成年女性膳食营养素摄入变化趋势

目的 了解中国成年女性膳食营养素摄入变化。方法 使用“中国健康与营养调查”2000－2011年数据,结合《中国居民膳食营养素参考摄入量速查手册(2013版)》,分析9省(区)25~55岁成年女性膳食能量及主要营养素摄入变化趋势。结果 2000－2011年9省(区)成年女性膳食能量和蛋白质摄入达到推荐量的人群比例不断下降,碳水化合物供能比过低(<50.0%)和脂肪供能比过高(>30.0%)的人群比例大幅增加。随时间变化,维生素和矿物质摄入状况同样不容乐观,多数微量营养素的达标比例过低,且该比例仍在继续下降。2011年成年女性能量和蛋白质摄入达到膳食推荐量的比例分别为43.0%和54.4%,碳水化合物供能比过低和脂肪供能比过高的比例分别为40.2%和63.8%;维生素A、硫胺素、核黄素、烟酸、维生素C和维生素E摄入达到推荐值的比例分别为25.2%、10.7%、6.9%、54.9%、24.3%和88.5%;钙、镁、铁、锌和硒的摄入量达到推荐值的比例分别为3.3%、23.6%、50.9%、75.7%和13.3%。结论 中国9省(区)成年女性膳食营养状况仍需改善,建议开展有针对性的营养教育和干预。     

Carbohydrates, appetite and feeding behavior in humans

The view of carbohydrates in relation to obesity has changed over the past few decades from being conducive to overconsumption and weight gain to being protective. This article reviews the mechanisms by which carbohydrate is purported to protect against weight gain. Although carbohydrate is metabolized and stored in the body less efficiently than fat, when de novo lipogenesis is invoked on very high carbohydrate diets, the beneficial effect on energy balance is likely to be minimal when typical high fat Western diets are consumed. However, it has been suggested that high carbohydrate foods may influence energy balance by reducing food intake through greater satiety effects, reducing energy density and displacing fat from the diet-the fat-sugar seesaw effect. To date, there seem to be few differences between sugars and starches on satiety and energy intake, but few studies have examined this. Some reduced-fat, and, therefore, higher carbohydrate, foods are highly energy dense. High carbohydrate foods do not necessarily have a low energy density. Evidence from recent studies suggests that adding carbohydrate, and especially sugar, to the diet neither displaces fat from the diet nor protects against elevated energy intake. Although it is easier to overeat on high fat than low fat foods, simply replacing fat with carbohydrate in the diet may not be as protective against overconsumption as the energy density or fat-sugar seesaw arguments suggest.     

Maternal carbohydrate intake and pregnancy outcome

Experimental evidence indicates that the primary maternal environmental factor that regulates feto-placental growth is substrate delivery to the placental site, which is the product of maternal substrate levels and the rate of placental-bed blood flow. Thus, maternal factors which change either substrate level or flow alter feto-placental growth rate. The best-studied substrate in human pregnancy is glucose, and there is a direct relationship between maternal blood glucose levels and size at birth. Altering the type of carbohydrate eaten (high- v. low-glycaemic sources) changes postprandial glucose and insulin responses in both pregnant and non-pregnant women, and a consistent change in the type of carbohydrate eaten during pregnancy influences both the rate of feto-placental growth and maternal weight gain. Eating primarily high-glycaemic carbohydrate results in feto-placental overgrowth and excessive maternal weight gain, while intake of low-glycaemic carbohydrate produces infants with birth weights between the 25th and the 50th percentile and normal maternal weight gain. The calculated difference in energy retention with similar total energy intakes is of the order of 80,000 kJ. Preliminary information from subsequent metabolic studies indicates that the mechanisms involved include changes in: daily digestible energy requirements (i.e. metabolic efficiency), substrate utilization (glucose oxidation v. lipid oxidation), and insulin resistance and sensitivity. Thus, altering the source of maternal dietary carbohydrate may prove to be a valuable tool in the management of pregnancies at risk for anomalous feto-placental growth and for the prevention and/or treatment of obesity and insulin resistance in the non-pregnant state.     

四川大学医学生膳食营养状况调查

目的了解高校医学生的膳食营养状况，为提高大学生的营养水平提供依据。方法编制半定量食物频率问卷，检验其信度和效度，并以此为调查工具，对330名医学生进行膳食调查。结果医学生的食物构成以粮谷类、蔬菜水果类、肉类为主，但能量来源比例不合理，脂肪供能过高，碳水化合物供能过低；钙摄入不足，优质蛋白质、动物源性铁与维生素A摄入不足。结论应教育学生合理改进膳食结构，增加优质蛋白质、碳水化合物、钙、动物源性铁，维生素A摄入量，以提高营养水平。     

Pre- and postgame macronutrient intake of a group of elite Australian football players

This study describes pre- and postcompetition mean energy and macro nutrient intakes of 40 elite Australian Football players. Carbohydrate intake, expressed both as a percentage of total energy intake (En%) and as grams per kilogram of body mass (g/kg BM). Pregame carbohydrate intake (53.6% En) was significantly greater (p < .01) than postgame (49.7% En). However, expressed as g/kg BM, pre- and postgame macronutrient intakes did not differ significantly. Protein and fat intakes (as g/kg BM) fell within guidelines, whereas energy intake (13.2 MJ/day or 153.8 kJ/kg BM) was lower than expected. Results suggest that for athletes engaging in endurance team sports where body mass and energy requirements vary considerably, carbohydrate recommendations are more appropriately expressed as g/kg BM rather than En %.     

Food intake measured by an automated food-selection system: relationship to energy expenditure.

Measuring food intake in a laboratory usually involves limited food choices. An automated food-selection system with two vending machines containing a large variety of foods was used to measure food intake in 10 male volunteers (31 +/- 6 y, 69.2 +/- 7.1 kg, 18 +/- 7% fat, mean +/- SD) on a metabolic ward. The effect of carbohydrate, fat, and protein intakes on 24-h energy expenditure (24EE) and substrate oxidations was measured in a respiratory chamber during day 4 of weight maintenance and day 7 of ad libitum intake. Ad libitum intake resulted in a 7-d overfeeding of 6468 +/- 3824 kJ/d above weight-maintenance requirements, leading to a 2.3 +/- 1.2-kg gain. The 10,975 +/- 3774 kJ excess energy intake on day 7 of ad libitum intake caused a 1205 +/- 920 kJ/d increase in 24EE (delta 24EE = 0.17 x delta intake - 695; r = 0.71, P less than 0.02). Of the excess carbohydrate intake, 74% was oxidized (r = 0.86, P less than 0.001), whereas excess fat intake was not. Carbohydrate and protein stores are regulated whereas excess fat intake is channeled to fat stores.