Role of energy expenditure in the development of pediatric obesity

The role that energy expenditure plays in pediatric obesity was somewhat confused by early research purporting to show that, as a group, obese children have lower energy intakes than do lean children. On the basis of this intake data, the conclusion was drawn that obese persons are somehow energy efficient, leading to weight gain. More recent research examining energy expenditure has shown clearly that, as a group, obese children have higher energy expenditures than do their lean counterparts. With the advent of the doubly labeled water method for determining free-living energy expenditure, it has been shown that obese children underreport intake significantly more than do lean children. When measurements are properly adjusted for differences in body size, there are generally no major differences in energy expenditure between lean and obese groups. However, in some cross-sectional studies, a low level of physical activity has been shown to be related to current body fatness. In addition, longitudinal studies have shown that a low level of energy expenditure, particularly energy expended in physical activity, is associated with both body fatness and weight gain.     

Effects of television on metabolic rate: potential implications for childhood obesity

The effects of television viewing on resting energy expenditure (metabolic rate) in obese and normal-weight children were studied in a laboratory setting. Subjects were 15 obese children and 16 normal-weight children whose ages ranged from 8 to 12 years. All subjects had two measured of resting energy expenditure obtained while at rest and one measurement of energy expenditure taken while viewing television. Results indicated that metabolic rate during television viewing was significantly lower (mean decrease of 211 kcal extrapolated to a day) than during rest. Obese children tended to have a larger decrease, although this difference was not statistically significant (262 kcal/d vs 167 kcal/d, respectively). It was concluded that television viewing has a fairly profound lowering effect of metabolic rate and may be a mechanism for the relationship between obesity and amount of television viewing.     

Effects of an acute exacerbation on nutritional and metabolic profile of patients with COPD

In this study, we investigated the influence of an acute disease exacerbation on the nutritional and metabolic status of patients with chronic obstructive pulmonary disease (COPD). The study group consisted of 23 patients acutely admitted to the hospital for standardized medical treatment. Dietary intake (dietary records and diet history), resting energy expenditure (ventilated hood), body composition (bioelectrical impedance spectroscopy) and disease symptoms (visual analogue scale) were assessed on admission, daily throughout the hospitalization period, at discharge and 3 months thereafter in stable clinical condition. Dietary intake, since aggravation of disease symptoms, prior to admission, (5,640+/-2,671 kJ) was significantly lower than habitual intake (7,863+/-2,005 kJ). The balance between dietary intake with measured resting energy expenditure and estimated diet-induced thermogenesis was severely impaired during the first 3 days of hospitalization, stabilizing thereafter to 145+/-24% at discharge. Resting energy expenditure decreased from 6,812+/-900 kJ (123+/-11%) on admission to 6,196+/-795 kJ (113+/-14%) at discharge (p<0.001). During treatment, no significant shift in water compartments, fat-free mass and body weight was seen. Follow-up data were obtained from 10 out of 23 patients. Three months after admission, dietary intake was not significantly different from usual dietary intake (8,512+/-2,290 and 8,415+/-2,600 kJ, respectively), resting energy expenditure was similar to the value at discharge, and a significant body weight gain was seen. We conclude that an acute exacerbation of chronic obstructive pulmonary disease is accompanied by an impaired energy balance due to a decreased dietary intake and an increased resting energy expenditure.     

The influence of sex hormones on obesity across the female life span

Women have a higher prevalence of obesity than men in most developed countries. Obesity affects many aspects of women's health by increasing risk for heart disease, diabetes, breast cancer, and infertility. One reason for the gender difference in obesity may be that fluctuations in reproductive hormone concentrations throughout women's lives uniquely predispose them to excess weight gain. Studies in experimental animals and women have shown that hormonal changes across the menstrual cycle affect calorie and macronutrient intake and alter 24-hour energy expenditure. Pregnancy is a significant factor in the development of obesity for many women. Various factors are associated with excess weight retention following pregnancy, including weight gain during pregnancy, ethnicity, dietary patterns, and interval between pregnancies. There is a need to tailor recommendations for energy intake during pregnancy to individual women, and recent evidence also suggests that the timing of weight gain during pregnancy is a critical factor. Menopause is also a high-risk time for weight gain in women. Although the average woman gains 2-5 pounds during menopausal transition, some women are at risk for greater weight gains. There is also a hormonally driven shift in body fat distribution from peripheral to abdominal at menopause, which may increase health risks in older women. Hormone therapies have varying impacts on body weight and fat distribution. In summary, hormonal fluctuations across the female life span may explain the increased risk for obesity in women. Awareness of these factors allows development of targets for prevention and early intervention.     

De novo lipogenesis predicts short-term body-composition response by bioelectrical impedance analysis to oral nutritional supplements in HIV-associated wasting

We studied the effects of enteral supplements on protein and energy intakes, body composition, energy expenditure, and gastrointestinal histology in 49 subjects with human immunodeficiency virus-associated weight loss (12.7 +/- 0.9% of body wt). We also determined whether a stable-isotope mass spectrometric measurement at baseline might predict the short-term response of fat-free mass (FFM) measured by bioelectrical impedance analysis. Thirty-nine subjects completed the study after being randomly assigned to receive either a whole-protein-based (n = 22) or a peptide-based (n = 17) formula. A nonsupplemented, nonrandomly assigned group (n = 13) was followed concurrently. Both formulas were well tolerated. Voluntary intakes of energy and protein from nonsupplement sources decreased significantly during supplementation [by 819-1638 kJ (196-382 kcal)/d and 5.6-14.4 g protein/d, respectively; P < 0.01] but to a lesser extent than the intake from the supplement [2300-2510 kJ(550-600 kcal)/d and 19-28 g protein/d, respectively], so that net increases in intakes of protein and energy (P < 0.03), as well as of several vitamins and trace elements were increased. Nevertheless, the mean FFM did not increase for the group as a whole, although there was considerable interindividual heterogeneity. Changes in FFM at 6 wk were significantly inversely correlated (r = 0.65, P < 0.01) with baseline synthesis of fat (de novo hepatic lipogenesis), but not with other potential measures of energy intake (insulin-like growth factor 1 or its binding protein) or inflammation (soluble tumor necrosis factor receptors I or II). The prospective identification of FFM response by measurement of de novo hepatic lipogenesis supported the hypothesis that the subset of wasting patients whose FFM is unresponsive to nutrient supplementation have altered nutrient metabolism.     

Energy expenditure of Chinese infants in Guangdong Province, south China, determined with use of the doubly labeled water method

The doubly labeled water method was used to measure the energy expenditure of a group of 41, 4- or 6-mo-old infants with a cross-sectional design. The infants were divided into two groups according to whether they were breast-fed (11 at 4 mo, 9 at 6 mo) or formula fed (11 at 4 mo, 10 at 6 mo). Anthropometric measurements were recorded at birth and at the beginning and end of the 8-d study. Anthropometric data, which were supported by the food intake and energy expenditure results, indicated that the infants were within the norms for European and American infants of the same age. Mean energy intakes of 352 kJ (84 kcal) kg(-1) x d(-1) at 4 and 6 mo were lower than the FAO/WHO/UNU recommended value of 452 kJ (108 kcal) x kg(-1) x d(-1)) and Chinese recommendations of 502 kJ (120 kcal) kg(-1) x d(-1). However, some authors believe that values of 398 kJ (95 kcal) kg(-1) x d(-1) at 4 mo and 356 kJ (85 kcal) kg(-1) x d(-1) at 6 mo are more appropriate. At 6 mo the infants' length-for-age and weight-for-age were at the National Center for Health Statistics 55th and 47th percentiles, respectively, whereas 58% were below the 50th percentile for weight-for-length. We conclude that at 4 mo infants receive sufficient energy for their requirements. However, at 6 mo energy requirements might well be greater than the revised recommendations, when infants are being weaned to alternative foods and are more prone to the influence of diet on their growth and development.     

Metabolic response to experimental overfeeding in lean and overweight healthy volunteers

Possible adaptive mechanisms that may defend against weight gain during periods of excessive energy intake were investigated by overfeeding six lean and three overweight young men by 50% above baseline requirements with a mixed diet for 42 d [6.2 +/- 1.9 MJ/d (mean +/- SD), or a total of 265 +/- 45 MJ]. Mean weight gain was 7.6 +/- 1.6 kg (58 +/- 18% fat). The energy cost of tissue deposition (28.7 +/- 4.4 MJ/kg) matched the theoretical cost (26.0 MJ/kg). Basal metabolic rate (BMR) increased by 0.9 +/- 0.4 MJ/d and daily energy expenditure assessed by whole-body calorimetry (CAL EE) increased by 1.8 +/- 0.5 MJ/d. Total free-living energy expenditure (TEE) measured by doubly labeled water increased by 1.4 +/- 2.0 MJ/d. Activity and thermogenesis (computed as CAL EE--BMR and TEE--BMR) increased by only 0.9 +/- 0.4 and 0.9 +/- 2.1 MJ/d, respectively. All outcomes were consistent with theoretical changes due to the increased fat-free mass, body weight, and energy intake. There was no evidence of any active energy-dissipating mechanisms.     

Voluntary food intake during prolonged exercise in obese women

The effect of 57 days of moderate physical activity on the energy intake and balance of three obese women (187% of ideal weight) was investigated in a metabolic balance study. Food was offered in extra quantity, prepared in a palatable but simple fashion, and intake was covertly monitored. Expenditure was measured using the factorial method and indirect calorimetry done every 3 to 4 days. After a 5-day evaluation phase which no exercise was done, individual treadmill assignments were given to subjects to increase daily expenditure to 125% of sedentary levels. Mean dialy intake (1903 kcal/day) and expenditure (2882 kcal/day) did not change with time. As a result, negative energy balance was obtained and sustained. A consistent rate of weight loss (0.12 kg/day) at a reasonable cost (8200 kcal/kg)occurred. Therefore, obese women doing long-term moderate exercise do not compensate by an increase in caloric intake. This can produce a negative caloric balance when exercise is coupled with ad libitum selection of ordinary foods.     

Resting energy expenditure and food-induced thermogenesis in obese children

Nineteen overweight girls 14.54 +/- 0.38 years of age were studied. Results were compared with those obtained in eight age-matched (14.07 +/- 0.51 years) and sex-matched normal weight controls. Energy expenditure (EE) was determined using open-circuit indirect calorimetry at rest, both after a 12-h fast and after an oral sucrose load of 3 g/kg ideal body weight. Food-induced thermogenesis (FIT) was evaluated by computing the area under the curve of the EE response above resting energy expenditure (REE) during the first 3 h after the sucrose load, REE (kcal/day) was higher in the overweight patients (1,818 +/- 46 vs. 1,527 +/- 67; p = 0.002); REE standardized by fat-free mass (FFM) (kcal/kg FFM/day) was lower in obese children than in controls (35.2 +/- 1.0 vs. 44.9 +/- 1.9; p = 0.0001). A linear correlation between REE and FFM was evidenced in both controls and overweight subjects (r = 0.78 and 0.68, respectively; p = 0.05 and p < 0.001, respectively). Actual REE in the obese children was significantly lower than the value predicted by applying the regression equation of REE on FFM in controls to the actual FFM in obese children (paired t test; p = 0.003). FIT was identical in overweight and normal weight subjects, regardless of whether it was expressed in absolute value, as the percentage calorie intake, or standardized by FFM.(ABSTRACT TRUNCATED AT 250 WORDS)     

A/T-rich sequences act as quantitative enhancers of gene expression in transgenic tobacco and potato plants

This study is the first to report approximations of energy requirements for male and female breast-fed and formula-fed infants based on individual estimates of total daily energy expenditure (TDEE) and energy deposition derived from total body fat (TBF) and fat-free mass (FFM) gain as determined by total-body electrical conductivity. In 46 healthy, full-term infants the effect of > or = 4 mo of exclusive breast-feeding compared with formula feeding on macronutrient and energy intake, TDEE, energy deposition, and growth were investigated prospectively. Metabolizable energy intake (MEI) was assessed from macronutrient intake by test weighing (MEI-TW) and from the sum of TDEE and energy deposition (MEI-Pred). At 1-2, 2-4, 4-8, and 8-12 mo of age MEI-Pred averaged 431 +/- 38, 393 +/- 33, 372 +/- 33, and 355 +/- 21 kJ x kg(-1) x d(-1) for boys, and 401 +/- 59, 376 +/- 25, 334 +/- 33, and 326 +/- 17 kJ x kg(-1) x d(-1) for girls. No significant difference between breast-fed and formula-fed infants was found with respect to weight, length, head circumference, TBF, FFM, and TDEE at all ages, or for gain in length, weight, TBF, and FFM. MEI-TW was significantly different between feeding groups at 1-4 mo of age (formula-fed being greater than breast-fed, P < 0.005). This feeding effect, however, was not significant for MEI-Pred (MJ/d). MEI-TW differed from MEI-Pred only in breast-fed infants at 1-4 mo (P < 0.05 at 2-4 mo). The data from this study indicate that energy requirements in infants are lower than the recommendations in guidelines currently in use.     

Effects of wine on plasma fibrinolytic and coagulation systems

Energy expenditure was estimated using the doubly-labelled water (DLW) method in summer in five free-living adult, non-pregnant, non-lactating, red deer (Cervus elaphus) hinds (weight 107.3 (SE 0.9) kg; age 6 (SE 1) years) on lowland pasture under typical farming conditions. Climatic conditions were monitored throughout the experiment. Errors due to 2H losses in CH4 and faeces were calculated from previous estimates of stoichiometries. CH4 production, fractionated water loss, urinary N and O2 consumption were estimated using an iterative approach. The water flux (rH2O) in these animals consuming only fresh grass was 12 (SE 0.5) kg/d, the CO2 production (rCO2) was 1271 (SE 40) litres/d and the mean energy expenditure was 25 (SE 0.8) MJ/d. There were no significant differences in the isotope distribution spaces and flux rates, rH2O, rCO2 or energy expenditure using the multi-point or two-point approaches to calculation. The DLW-derived energy expenditure of 25 MJ/d is approximately 20% higher than the recommended intake of 21 MJ/d for adult hinds kept outdoors (Adam, 1986) and, at 757 kJ/kg0.75 per d, one third higher than the value of 570 kJ/kg0.75 per d for stags penned indoors (Key et al. 1984).     

Modulation of calcium and potassium currents by lamotrigine

In a prospective noninterventional study of 75 consecutive patients (mean age 71 +/- 12 years) undergoing surgery for colorectal cancer, standard postoperative energy intake was evaluated. Seventeen patients expended 40%-60% of estimated basal energy during hospitalization, 33 patients 60%-80%, 22 patients 80%-100% and three patients 100%-125%. Weight loss was observed in 67 patients (mean loss 4.7 +/- 4.4%) during hospitalization. Men had a significantly higher mean total calorie deficit (p < 0.001), and mean weight loss percentage (p < 0.01), compared to women. Preoperative nutritional status, nutrition-associated complications and length of hospital stay did not change the nutritional support and intake. Correlation analyses resulted in significant associations between gender and total calorie deficit (rs = 0.41, p < 0.01), postoperative weight loss and total calorie deficit (rs = -0.32, p < 0.01), and between postoperative weight loss and length of stay (rs = 0.27, p < 0.05). We concluded that the patients' energy intake was insufficient compared to estimated basal energy expenditure. These results suggest a need for individualized nutritional care, based on each patient's energy needs and on registration of daily calorie intake, all with the aim of increasing energy intake postoperatively in standard hospital care.     

High prevalence of obesity in low income and multiethnic schoolchildren: a diet and physical activity assessment

The objective of the study was to assess the prevalence of obesity and/or undernutrition and evaluate diet and activity patterns among schoolchildren from an ethnically diverse low income urban population. A cross-sectional survey of 498 children aged 9-12 y from 24 schools in low income multiethnic neighborhoods in Montreal, Canada was undertaken. Height, weight, dietary intake, physical activity record, and lifestyle and demographic characteristics were measured. There was no evidence of undernutrition because linear growth was appropriate for age, but 39.4% of children were overweight (>85th percentile NHANES II). Dietary fat intake was higher in children from single-parent families (P < 0.001) and those with mothers born in Canada. Intake of vitamins A, C, iron and folate was directly related to income sufficiency. Children who did more physical activity had significantly higher intakes of energy, calcium, iron, zinc and fiber but were not heavier. Dietary intake was systematically underreported among overweight children, i.e., their reported intakes did not meet calculated energy needs. This underreporting makes it difficult to attribute the accumulated energy imbalance to either energy intake or expenditure.     

Energy metabolism in sedentary and active 49- to 70-yr-old women

This study examined differences between long-term exercising (LE) and long-term nonexercising (LNE) women [n = 24; age 56.4 +/- 6.2 (SD) yr] for resting metabolic rate (RMR) and energy expenditure in the free-living state by using doubly labeled water (DLW). There was a statistically significant difference (P = 0.0002) between the 12 LE (94.85 +/- 8.44 kJ . kg-1 . day-1) and 12 LNE (81.16 +/- 6.62 kJ . kg-1 . day-1) for RMR, but this difference was only marginally significant (P = 0.06) when the data (MJ/day) were subjected to an analysis of covariance with fat-free mass as the covariate. The DLW data indicated that the eight most active LE (12.99 +/- 3.58 MJ/day) expended significantly (P = 0.01) more energy than did the eight least active LNE (9.30 +/- 1.15 MJ/day). Energy expenditures ranged from 7.64 to 18.15 MJ/day, but there was no difference (P = 0.96) between the LE and LNE in energy expenditure during activity that was not designed to either improve or maintain fitness. These cross-sectional data on 49- to 70-yr-old women therefore suggest that 1) aerobic-type training results in a greater RMR per unit of body mass and also when statistical control is exerted for the effect of the metabolically active fat-free mass, 2) there is a large range in the energy intake necessary to maintain energy balance, and 3) aerobic training does not result in a compensatory reduction in energy expenditure during the remainder of the day.     

Alpha-linolenic acid and marine long-chain n-3 fatty acids differ only slightly in their effects on hemostatic factors in healthy subjects

The effects of alpha-linolenic acid (ALA, 18:3n-3), eicosapentaenoic acid (EPA, 20:5n-3), and docosahexaenoic acid (DHA, 22:6n-3) on hemostatic factors were compared. Healthy subjects (29 women and 17 men aged 20-44 y) received either linseed oil (average ALA intake: 5.9 g/d) or fish oil plus sunflower oil (average EPA + DHA intake: 5.2 g/d) for 4 wk. The supplemented amount of fat was 1.19 mg/kJ (1 g/200 kcal) calculated energy expenditure. Stability of habitual diets was monitored. Blood samples were collected at baseline, at the end of the experimental period, and after a 12-wk follow-up period. Different changes in the study groups were seen only in serum cholesterol and triacylglycerols, platelet fatty acid composition, and ADP-induced platelet aggregation. The treatments did not differ in their effects on collagen-induced platelet aggregation and thromboxane production, aggregation to the thromboxane A2 mimic I-BOP, urinary excretion of 11-dehydro-thromboxane B2 and beta-thromboglobulin, bleeding time, plasma fibrinogen concentration, antithrombin III activity, factor VII coagulant activity, or activity of plasminogen activator inhibitor 1. The results indicate that supplemented ALA from vegetable oil and EPA and DHA from a marine source have largely parallel effects on hemostatic factors.     

Metabolizable energy intake and sustained energy expenditure of Alaskan sled dogs during heavy exertion in the cold

OBJECTIVE: To measure energy expenditures of Alaskan sled dogs at rest and during racing under frigid conditions, using the doubly labeled water (DLW) technique. ANIMALS: 18 fit Alaskan sled dogs. PROCEDURE: Energy expenditure was measured in 9 dogs during a 490-km sled dog race by use of the DLW technique, whereby dogs were administered water enriched with nonradioactive isotopes of hydrogen and oxygen. Energy intake was determined by dietary analysis. Changes in background abundance of the isotopes 2H and 18O were monitored in 5 dogs that did not receive isotope-enriched water. RESULTS: Dogs completed the 490-km race at an average speed of 7 km/h at ambient temperature of -35 to -10 C. Total energy expenditure, measured by the DLW technique, was 47,100 +/- 5,900 kJ/d (4,400 +/- 400 kJ.kg-0.75/d), and metabolizable energy intake was 44,600 kJ/d (4,100 kJ.kg-0.75/d) during the 70-hour race. CONCLUSIONS: The sustained metabolic rate for these sled dogs during racing was extraordinarily high for a large mammal. This study validated use of the DLW technique in dogs with exceptionally high energy expenditure associated with prolonged exercise in the cold.     

Intrahousehold allocation of energy intake among children under five years and their parents in rural Bangladesh

OBJECTIVE: This study assesses intrahousehold allocation of energy in rural Bangladesh and tests the hypothesis that, when daily energy intake is adjusted for energy expenditure, no age or gender bias will be apparent in intrahousehold energy allocation. DESIGN: Data were collected at two-month intervals over a one year study. SETTING: Four villages in Matlab Thana, rural Bangladesh. SUBJECTS: Two hundred and seven children up to 5 y of age and their 145 mothers and 123 fathers. INTERVENTIONS: Data included six measurements of observed 24 h dietary energy intake and physical activity recorded from waking to sleeping. Total daily energy expenditure was derived using the factorial method. RESULTS: Women's energy intake ranged from 75-88% of the FAO/WHO recommended energy intake over the six periods of data collection, significantly less (P < 0.0001) than the men's (range 89-114%). Although the women had moderate levels of physical activity, frequent pregnancies and long lactation periods increased their energy needs. Among children no longer breast fed, energy consumption, unadjusted for energy expenditure, provided 86-108% of the FAO/WHO recommended energy intake by weight. CONCLUSIONS: Women consistently received less of their energy requirements than either their children or their husbands.     

Pressure-controlled nephrostography

A study was made during a 3-month period of the food intake of all patients older than 60 years, who were admitted to a ward of acute orthopedic surgery. This amounted to 31 women and 15 men, whose average age was 74 years. Each patient's diet was studied for 16 days on an average. The mean daily energy intake was 1 163+/-341 kcal (4 868 +/- 1 427 kJ) for women and 1 558+/-539 kcal (6 521+/-2 856 kJ) for men. 44 of 46 patients received fewer calories than is recommended for healthy persons the same age, and 25 of 46 patients consumed less calories per day than the basal metabolism. The mean daily protein intake was 0.7+/-0.3 g/kg/day for both men and women. 28 of the patients received less than 0.8 g/kg/day which is the amount of protein recommended healthy adults and none of our patients received 1.5 g protein/kg/day, the protein intake recommended patients in hospital. The low protein intake was due to a poor intake of energy as well as a high consumption of refreshing drinks and titbits, both a little nourishment.     

Total and resting energy expenditure in obese women reduced to ideal body weight

Obesity could be due to excess energy intake or decreased energy expenditure (EE). To evaluate this, we studied 18 obese females (148 +/- 8% of ideal body weight [IBW], mean +/- SD) before and after achieving and stabilizing at IBW for at least 2 mo and a control group of 14 never obese females (< 110% of IBW or < 30% fat). In the obese, reduced obese, and never obese groups, the percent of body fat was 41 +/- 4%, 27 +/- 4%, and 25 +/- 3%; total energy expenditure (TEE) was 2704 +/- 449, 2473 +/- 495, and 2259 +/- 192 kcal/24 h; while resting metabolic rate was 1496 +/- 169, 1317 +/- 159, and 1341 +/- 103 kcal/24 h, respectively. 15 obese subjects who withdrew from the study had a mean initial body composition and EE similar to the subjects who were successful in achieving IBW. In 10 subjects followed for at least one year after stabilizing at IBW there was no significant relationship between the deviation from predicted TEE at IBW and weight regain. These studies indicate that, in a genetically heterogeneous female population, neither the propensity to become obese nor to maintain the obese state are due to an inherent metabolic abnormality characterized by a low EE.     

Schistosoma mansoni: the varying occurrence of repetitive elements in different strains shows sex-specific polymorphisms

In this Grand Round, two children are described with atypical generalized scleroderma and severe failure to thrive. Neither had Raynaud's phenomenon nor evidence of gastrointestinal (GI) disease. Treatment with non-steroidal anti-inflammatory drugs, prednisone, D-penicillamine, alpha and gamma interferon was unsuccessful in reversing the sclerodermatous changes and growth arrest. Dietary intake analysis and extensive GI investigation were performed in both. In one case, resting energy expenditure (Ee) was repeatedly measured. His intake did not meet requirements for growth. Supplemental tube feeding (900 kcal in 6 h) was commenced, causing an increase in weight from 11 to 16 kg. The other patient refused supplementary tube feeding and no weight gain has been observed for 5 yr. In conclusion, early-onset generalized scleroderma in the absence of visceral involvement, but with growth failure, may represent an atypical form of systemic sclerosis. The response of the two patients to conventional therapy was disappointing. However, the rapid catch-up growth induced by tube feeding observed in one patient underlines the importance of adequate dietary management.