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PubMed1993

Effect of exercise and protein intake on energy expenditure in adolescents.

In order to evaluate the influence of physical exercise and protein intake on Resting Metabolic Rate (RMR) and Postprandial Energy Expenditure (PEE), 16 healthy, normal-weight, 15 year-old, adolescent males at the same stage of pubertal development were studied. They were assigned to two dietary groups receiving the same energy intake (1.3 x by measured RMR) and different proportions of macronutrients (13% protein, 39% fat, 48% CHO in Group A; 30% protein, 32% fat, 38% CHO in Group B). An increase in postprandial energy expenditure, relative to basal, was observed in all individuals. The postprandial energy expenditure was higher in group B than in group A. Postprandial Post-exercise Thermogenesis (expressed as Kcal/3 h) was significantly higher in group B than group A (p < 0.05). Although the RMR on the test day was not different between the groups, the RMR on day 2 was significantly higher than on day 1 in group B (p < 0.01). In group B, the post-exercise RQ was significantly lower than the preexercise RQ (p < 0.01). It is concluded that in normal-weight-adolescents, a hyperproteic diet followed by moderately-intensive exercise induces increases in EE and decreases in RQ in the postprandial post-exercise period and is accompanied by increase in the RMR the following day.

Adolescent↗

PubMed1984

Whole-body calorimetry studies in adult men. 1. The effect of fat over-feeding on 24 h energy expenditure.

Eight young men of normal weight were maintained for 1 week on a weight-maintenance diet followed by a 1-week period of over-feeding with extra fat designed to increase energy intake by 50%. Two 36 h calorimetry sessions with low and high physical activities were included in each feeding period. Faecal and urine collections permitted checks on energy malabsorption and nitrogen excretion. Over-feeding led to increases in body-weight, faecal energy and N excretion and in estimated N retention. Faecal energy outputs on the maintenance and over-feeding diets were 5 and 4.4% of the respective gross energy intakes. Energy expenditure on fat over-feeding increased by 5.6% on the low-activity regimen and 6.4% on the high-activity regimen. This amounted, in terms of the extra energy intake, to 9 and 11% on the inactive and active schedules respectively. The increase affected day- and night-time rates of energy expenditure plus the basal metabolic rate. Individuals with a low percentage body fat showed the greatest response to over-feeding. Nutrient-balance studies derived from calorimetry suggested that fat over-feeding led to substantial fat deposition with no evidence of sparing of carbohydrate oxidation. The theoretical cost of depositing dietary fat was exceeded, suggesting that regulatory thermogenic mechanisms may have been stimulated to a small extent.

Adult↗

PubMed2004

Trends in intake of energy and macronutrients--United States, 1971-2000.

During 1971-2000, the prevalence of obesity in the United States increased from 14.5% to 30.9%. Unhealthy diets and sedentary behaviors have been identified as the primary causes of deaths attributable to obesity. Evaluating trends in dietary intake is an important step in understanding the factors that contribute to the increase in obesity. To assess trends in intake of energy (i.e., kilocalories [kcals]), protein, carbohydrate, total fat, and saturated fat during 1971-2000, CDC analyzed data from four National Health and Nutrition Examination Surveys (NHANES): NHANES I (conducted during 1971-1974), NHANES II (1976-1980), NHANES III (1988-1994), and NHANES 1999-2000. This report summarizes the results of that analysis, which indicate that, during 1971--2000, mean energy intake in kcals increased, mean percentage of kcals from carbohydrate increased, and mean percentage of kcals from total fat and saturated fat decreased. An expert advisory committee appointed by the U.S. Department of Health and Human Services and the U.S. Department of Agriculture (USDA) is conducting a review of the Dietary Guidelines for Americans. Revised guidelines will be published in 2005.

Adult↗

PubMed2005

Exogenous recombinant human growth hormone effects during suboptimal energy and zinc intake.

BACKGROUND: Energy and Zinc (Zn) deficiencies have been associated with nutritional related growth retardation as well as growth hormone (GH) resistance. In this study, the relationship between suboptimal energy and/or Zn intake and growth in rats and their response to immunoreactive exogenous recombinant human GH (GHi), was determined. RESULTS: Rats treated with GHi and fed ad-libitum energy and Zn (100/100) had increased IGFBP-3 (p < 0.05) as compared with NSS (215 +/- 23 vs. 185 +/- 17 ng/ml) along with similar body weight gain. Rats treated with GHi and fed suboptimal energy and full Zn (70/100) had significantly increased weight gain (109.0 +/- 18.2 vs. 73.8 +/- 11.0 g) and serum IGF-I levels (568 +/- 90 vs. 420 +/- 85 ng/ml), along with decreased total body water (TBW; 61.0 +/- 1.6 vs. 65.7 +/- 2.1%) as compared to NSS controls. However, body weight gain was reduced (p < 0.05) as compared with rats fed ad-libitum energy. Growth hormone treated rats fed only suboptimal Zn (100/70), had increased weight gain (217.5 +/- 13.2 vs. 191.6 +/- 17.9 g; p < 0.05) compared to those given NSS. These rats gained weight in similar amounts to those fed full Zn. Rats treated with GHi and fed both suboptimal energy and Zn (70/70) showed similar results to those fed suboptimal energy with appropriate Zn (70/100), along with significant increases in IGFBP-3 levels (322 +/- 28 vs. 93 +/- 28 ng/ml). All restricted rats had reduced 24-h EE (kcal/100 g BW) and physical activity index (oscillations/min/kg BW) and GHi did not overcome these effects. CONCLUSION: These results suggest that GHi enhances weight gain in rats with suboptimal energy and Zn intake but does not modify energy expenditure or physical activity index. Suboptimal Zn intake did not exacerbate the reduced growth or decrease in energy expenditure observed with energy restriction.

Journal Article↗

PubMed1991

Intake of energy and nutrients. Euronut SENECA investigators.

As part of the Euronut SENECA study, food consumption has been assessed in 1217 men and 1241 women, born between 1913 and 1918 and living in 18 towns in 12 European countries. The method used was a standardized modified dietary history, including a 3-day estimated record and a food frequency list based on local food patterns. Intakes of energy, protein, fat, carbohydrate, fatty acids, cholesterol and alcohol are described in this paper. As expected, a difference between men and women in energy and nutrient intake was observed in all towns. There was a great variation between towns in mean dietary intakes of all dietary components. Mean energy intake of men ranged from 12.7 MJ in Marki (Poland) to 8.2 MJ in Yverdon (Switzerland) and Chateau Renault-Amboise (France). For women the range was from 10.9 MJ in Marki (Poland) to 6.3 MJ in Yverdon (Switzerland) and Vila Franca de Xira (Portugal). A geographical pattern can be detected for the intake of fatty acids. Intakes of saturated fat were lower in southern than in northern European towns. The calculated ratio for intakes of unsaturated and saturated fatty acids (polyunsaturated fatty acids plus monounsaturated fatty acids/saturated fatty acids) for all participants was higher in the southern European centres than in the northern centres and ranged from 2.7 in Markopoulo (Greece) to 1.2 in Elverum (Norway) and Marki (Poland). Alcohol consumption was considerable higher in men than in women. In men a north-south gradient in alcohol intake can be detected, with the highest intake in the two centres in Italy, where, on average 11% of energy intake was derived from alcohol.

Aged↗

PubMed1997

Dietary adherence in children with familial hypercholesterolemia.

We examined nutritional and psychosocial factors associated with adherence to the recommended diet (< or = 30% of energy from fat and < 10% from saturated fat) in children with familial hypercholesterolemia. Ninety-eight boys and 74 girls aged 7-17 y treated for > or = 18 mo responded to a quantitative food-frequency questionnaire that was self- (ages 13-17 y) or dietitian-(ages 7-12 y) administered. One hundred nine subjects also completed a weighed food record. Psychosocial assessments included the Child Behavior Checklist, Youth Self Report, and Children's Global Assessment Scale. The weighed record showed better adherence to dietary guidelines than the food-frequency questionnaire, but energy intake was underestimated. Low energy reporters had a healthier diet than the rest with the weighed record. According to the questionnaire, energy intake was underreported in only 9% of subjects and was not associated with a healthier diet, thus, further analyses were based on the questionnaire. Intakes of vitamin C (P = 0.0001), folate (P = 0.0001), riboflavin (P = 0.03), thiamine (P = 0.0001), and magnesium (P = 0.0001) per megajoule increased as quartile of total fat intake (as a % of total energy) decreased, reflecting increased intakes of cereals (P = 0.002), pasta (P = 0.01), fruit (P = 0.0001), pure meat (not minced or meat products; P = 0.047), skim milk (P = 0.0001), and skim cheese (P = 0.005). Energy and sugar (% of total energy) intakes were not significantly different across all fat intakes; energy density decreased with decreasing fat quartile. Overall psychosocial function score and parental educational level were associated with lower fat intake in multivariate analysis, explaining 11% of the variance in fat intake. We conclude that adherence to fat restriction among children treated for familial hypercholesterolemia is associated with increased micronutrient density, decreased energy density, and psychosocial factors that facilitate adherence.

Adolescent↗

PubMed1993

Intake of energy, nutrients and food items in an urban elderly population.

This study is part of a transcultural investigation under the auspices of the International Union of Nutritional Sciences, where dietary habits are studied with similar methodology in different populations throughout the world. The present paper describes and evaluates the intake of energy and nutrients, and food habits in an urban elderly population in Sweden, in relation to existing standards. The study population comprised 66 males and 122 females, aged 70 years and over (average 78 years) living in the city of Gothenburg. Energy intake was on average 11.5 MJ in males and 9.9 MJ in females. Nutrient intakes were on average above recommendations, and neither intake nor food choice seemed to change much with increasing age. A validation by a 4-day record and 24-hour urinary nitrogen determination was performed in a subsample, and indicated a probable systematic overestimation of at least 10% for protein consumed. The data from this study support the view that people 70 years of age and older in Sweden are generally healthy, active and have good food habits. This population, however, was not a representative sample. They were all living in a well defined area, with a stable social situation, and belonged generally to middle class. With this background the nutrient data seem reasonable. As long as elderly people stay healthy and do not have other serious risk factors, they seem to keep good food habits and nutritional status up into their eighties and nineties.

Aged↗

PubMed1994

The implications of underreporting in dietary studies.

Dietary data from the Western Sydney Dietary Survey 1989-90 (n = 512) was used to investigate: 1. the prevalence and predictors of underreporting of energy intake, 2. the effects on results of excluding data from underreporters for analysis of mean nutrient intakes, and 3. the proportion of energy intake supplied by macronutrients and proportions of subjects who met dietary goals. The proportion whose measured energy intakes from a Food Frequency Questionnaire (FFQ) were below cutpoints for biologic plausibility was 28.5 per cent; it was higher for subjects who had BMI > 25 and were female. Point estimates for mean intakes of energy and nutrients were all greater when data from underreporters were excluded, but nutrient intakes expressed as percentages of energy intake remained largely unchanged. Increases in estimated mean population intake for each nutrient ranged from 7 per cent to 14 per cent for males, and 12 per cent to 17 per cent for females. Estimates of the percentages of the sample who did not meet dietary goals were significantly lower for a number of nutrients when underreporters were excluded. We conclude that: 1. results expressed as a percentage of energy intake are not affected by the exclusion of energy underreporters, and 2. estimates of the proportion of populations meeting some nutrient goals and associations between diet and disease are likely to change meaningfully and significantly with the exclusion of data from underreporters.

Adult↗

PubMed1976

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.

Altitude↗

PubMedDate not supplied

Plasma urea, creatinine, and urea: creatinine ratio in reindeer (Rangifer tarandus tarandus) and in Svalbard reindeer (Rangifer tarandus platyrhynchus) during defined feeding conditions and in the field.

Variation in plasma urea and creatinine concentration and plasma urea:creatinine ratio (U:C) were studied in semidomestic free-ranging reindeer (Rangifer tarandus tarandus) on the Norwegian mainland, in wild Svalbard reindeer (Rangifer tarandus platyrhynchus), and in captive reindeer maintained either on a lichen-based diet or a protein-rich concentrate to investigate whether these parameters could be used as indicators of the nutritional status of reindeer. In the mainland animals, plasma creatinine concentration was high in winter and early spring and decreased by two-thirds toward the summer. The overall range in mean plasma creatinine concentration (+/-SE) was from 90+/-1.26 to 280+/-2.88 micromol/L. Mean plasma urea concentration (+/-SE) varied from 2.46+/-0.10 in winter up to 17.44+/-0.29 mmol/L in summer and autumn. Month of sampling explained 65% and 90% of the variation in plasma urea and creatinine concentrations, respectively, indicating that seasonality in the diet had the greatest influence on these parameters. Reindeer given lichens as the only feed showed an increase in plasma creatinine and a decrease in plasma urea concentration. Food restriction caused a temporary elevation in urea level but had no significant effect on plasma creatinine concentration. The slight effect of energy intake on urea and creatinine levels was supported by the fact that severe undernutrition in the Svalbard reindeer population had only a small effect on plasma urea and creatinine levels. Protein-rich pellet feed increased plasma urea from around 3 mmol/L to above 10 mmol/L and reduced creatinine concentrations to less than 100 micromol/L, suggesting that the protein content of forage is an important determinant of these blood parameters. Mean U:C ratio (+/-SE) in plasma varied from 8.9+/-0.28 to 120.8+/-1.88. Ratios above 20 appeared when protein intake was low and energy intake was restricted or when protein intake was high. Low ratios occurred when protein intake was low but energy intake adequate. Plasma urea and creatinine concentrations and the U:C ratio showed complex dynamics that were affected by both season and the protein and feed intake. We conclude that they appear to be difficult to interpret as single measures of nutritional status of reindeer.

Animals↗

PubMed2006

Nutritional parameters and mortality in incident hemodialysis patients.

OBJECTIVE: To evaluate the impact of nutritional parameters at the time of initiation of hemodialysis (HD) on mortality. DESIGN: Retrospective study. SETTING: Dialysis Unit of the Federal University of Sao Paulo, Oswaldo Ramos Foundation. PATIENTS: Three hundred forty-four incident HD patients (60.5% male, 26% diabetic) with the first nutritional evaluation performed before completing 3 months of onset of HD were included. METHODS: The study consisted of baseline measurements of several nutritional parameters (triceps skinfold thickness [TSF], midarm muscle circumference [MAMC], body mass index [BMI], serum albumin, serum creatinine, and protein and energy intake assessed by 3-day food diary) and records of outcome (death) over a period of 10 years. RESULTS: Muscle and/or fat depletion was observed in 51% of the studied patients, according to the percent standard of MAMC and TSF, respectively. Presence of diabetes, age over 60 years, serum albumin < 3.5 g/dL, MAMC adequacy < 90%, protein intake < 1.0 g/kg/d, and energy intake < 25 kcal/kg/d were associated with worse survival. When patients were analyzed according to tertiles of dialysis vintage, BMI > or = 25 (calculated as kg/m2) had a negative impact on survival only in the highest tertile (> 2.45 years). Patients with BMI < 25 and MAMC adequacy > or = 90% showed the best survival over the study period, and those with BMI > or = 25 but MAMC adequacy < 90% had the worst survival (P = .004). In the multivariate survival analysis adjusting for diabetes, advanced age, and hypoalbuminemia, the reduced MAMC (P = .008) and the low energy intake (P = .03) were independent predictors of death in incident HD patients. CONCLUSIONS: Reduced MAMC and low energy intake at the beginning of chronic dialysis are risk factors for mortality. A negative effect of high BMI on survival was associated with reduced MAMC and longer dialysis vintage.

Adipose Tissue↗

PubMedDate not supplied

Energy and nitrogen balance and changes in midupper-arm circumference with multiple organ failure.

Energy intake and energy expenditure, nitrogen intake, and urinary nitrogen excretion (or urea production rates) were measured in 35 intravenously fed patients with multiple organ failure over the course of their illness to determine to what extent nutrient requirements were met despite fluid retention. Energy and nitrogen balance were related to serial measurements of midupper-arm circumference (MAC). The target feeding regimen of 176 kJ (42 kcal)/kg fat-free mass (FFM) was achieved in only three patients and the target of 0.24 g N/kg FFM in only four. Two patterns of change in MAC were noted: a steady decrease with time and no change with time. Serial muscle biopsy data indicated that all the patients were wasting away; the maintenance of MAC in the group with no change over time was due to fluid retention. Abnormal losses were not measured, but energy and nitrogen balance in the group in which arm circumference decreased had no apparent effect on the rate of wasting.

Adolescent↗

PubMed1990

Contributions of food groups to intakes of energy, nutrients, cholesterol, and fiber in women's diets: effect of method of classifying food mixtures.

This study examined the effect of using two different methods for categorizing food mixtures when calculating the contribution of various food groups to energy, macronutrient, cholesterol, and fiber intakes. Using method 1, each food mixture was classified as a single item and assigned to a food group according to its main ingredient. Using method 2, most of the food mixtures were separated into their constituent ingredients, and each ingredient was assigned to its appropriate food group. Data were from 1,032 women who provided at least 4 days of dietary data in the U.S. Department of Agriculture's 1985 Continuing Survey of Food Intakes by Individuals. We found that the importance of each food group's contribution to individual dietary components varied depending on the method used to categorize the food mixtures. When food mixtures were separated into their constituent ingredients before assigning foods to food groups, the contributions of meat, fish, poultry, and grain products declined for each of the seven dietary components studied. At the same time, the contributions of milk products, fats, and oils increased for most of the seven components. The results highlight the importance of foods eaten as part of food mixtures to the intake of energy, macronutrients, cholesterol, and fiber.

Adult↗

PubMed1989

Growth, food intake and energy balance of layer and broiler chickens offered glucose in the drinking water and the effect of dietary protein content.

1. Four experiments were carried out to study the effect of offering a 91.5 g/l solution of glucose, compared to tap water, on fluid intake, food intake and growth of individually-caged immature chickens of both layer and broiler strains. 2. Male chicks of an egg-laying strain were offered glucose solution or tap water from 27 to 62 d after hatching. There was no effect of glucose on fluid intake but it depressed food intake (P less than 0.01) to give equal total energy intakes for each treatment. Body weight gain was reduced (P less than 0.001) and carcase fat content increased (P less than 0.001) by the glucose to yield no difference to total carcase energy. 3. When birds were placed in a respiration chamber for two 23-h periods there was no effect of treatment on outputs of energy as faeces + urine or as heat. 4. Male broilers were offered glucose solution or tap water with diets containing either 150 or 195 g protein/kg from 20 to 55 d after hatching. With the low-protein diet glucose depressed food intake (P less than 0.01) but total energy intake and carcase energy were not significantly affected. With the high-protein diet glucose did not depress food intake but increased total energy intake and total body fat. 5. Layer and broiler chicks were offered either a choice of the low- and high-protein diets or a single diet intermediate in protein content, with glucose solution or tap water. With broilers total food intake was depressed by glucose, mainly by a reduced intake of the low-protein diet. Intake of neither diet by the layer chicks was significantly affected by glucose. 6. It is concluded that provision of extra energy in glucose solution depresses food intake when the resultant energy:protein ratio becomes limiting. With a higher protein diet, or with birds having lower protein requirements, glucose solution does not depress food intake and increased fat deposition occurs.

Animals↗

PubMed2002

Neuropeptides and appetite control.

Obesity is important in the aetiology of type 2 diabetes, and presents a major barrier to its successful prevention and management. Obesity develops when energy intake exceeds energy expenditure over time. A complex system has evolved to maintain energy homeostasis, but this is biased towards weight gain. Meal size is controlled by a series of short-term hormonal and neural signals that derive from the gastrointestinal tract, such as cholecystokinin whereas others may initiate meals, such as the recently discovered hormone, ghrelin. Other hormones such as insulin and leptin, together with circulating nutrients, indicate long-term energy stores. All these signals act at several central nervous system (CNS) sites but the pathways converge on the hypothalamus, which contains a large number of peptide and other neurotransmitters that influence food intake. As energy deficit is most likely to compromise survival, it is not surprising that the most powerful of these pathways are those that increase food intake and decrease energy expenditure when stores are depleted. When energy stores are low, production of leptin from adipose tissue, and thus circulating leptin concentrations fall, leading to increased production of hypothalamic neurotransmitters that strongly increase food intake, such as neuropeptide Y (NPY), galanin and agouti-related protein (AGRP) and decreased levels of alpha-melanocyte-stimulating hormone (alpha-MSH), cocaine and amphetamine-regulated transcript (CART) and neurotensin that reduce food intake and increase energy expenditure. The finding that mutations in leptin and POMC lead to severe early onset obesity in humans has highlighted the importance of these peptides in humans. This new understanding may eventually lead to new treatments for obesity that will be of particular benefit in the prevention and treatment of type 2 diabetes.

Appetite↗

PubMed2000

The corticotropin-releasing hormone system in the regulation of energy balance in obesity.

The view that energy balance is regulated has gained acceptance in recent years. An important role in this regulation is played by brain circuitries involved in the control of energy intake (food intake) and energy expenditure (thermogenesis) that are capable of integrating peripheral signals, produced by perturbations of adipose tissue mass, into messages to effectors of food intake and energy expenditure, so as to prevent substantial variations in the level of energy reserves. More than one neurosystem has been reported to genuinely participate in the regulation of energy balance. Among them is the corticotropin-releasing hormone (CRH) system. This system, with its numerous clusters of brain neurons, its closely related peptide urocortin, its two receptor types and its binding protein, all generally widely distributed throughout the brain, forms a network of neuronal pathways capable of interacting with the circuitries controlling food intake and energy expenditure. In addition, CRH and urocortin's anorectic and thermogenic actions appear to be coordinated to optimize energy losses. Finally, the CRH system seems to demonstrate a certain degree of plasticity in obesity and in response to food deprivation that is consistent with its action on food intake and thermogenesis. The observations have been made that food deprivation and obesity can blunt the expression of the CRH type 2alpha receptor in the ventromedial hypothalamic nucleus and can induce the expression of the CRH-binding protein (a CRH-inactivating protein) in brain areas involved in the anorectic and thermogenic actions of CRH.

Brain↗

PubMed1984

Prediction of weights in humans after overfeeding using the Payne-Dugdale model.

Payne & Dugdale (1977) have proposed a model for predicting body weight in humans when the individual lean : fat tissue deposition ratio, energy intake +/- s.d. and energy expenditure +/- s.d. are known. The model was tested in 8 individuals, whose actual weights, energy intakes and expenditures (with their standard deviations) for a normal period, a semi-starvation period and an overfeeding period of 2 weeks were known or estimated. With the model, the lean : fat tissue deposition ratio for each person was calculated from the data of the semi-starvation period. From this ratio the model was able to predict a body weight equal to the one observed for the normal period. For the overeating period, the model predicted body weights which were considerably higher than the ones observed. Some explanations for this phenomenon are discussed.

Adipose Tissue↗

PubMed2003

Estimation of energy requirements in a controlled feeding trial.

BACKGROUND: Estimating energy requirements is a frequent task in clinical studies. OBJECTIVE: We examined weight patterns of participants enrolled in a clinical trial and evaluated factors that may affect weight stabilization. The Harris-Benedict equation and the FAO/WHO equation, used in conjunction with physical activity levels estimated with the 7-d Physical Activity Recall, were compared for estimating energy expenditure. DESIGN: This was a multicenter, randomized controlled feeding trial with participants of the Dietary Approaches to Stop Hypertension Trial. For 11 wk, the amount of food participants received was adjusted to maintain their body weights as close to their initial weights as possible. Change-point regression techniques were used to identify weight-stable periods. Factors related to achieving weight stabilization were examined with logistic regression. RESULTS: A stable weight was achieved by 86% of the 448 participants during the run-in period and by 78% during the intervention period. Energy intake averaged 11 +/- 2.4 MJ/d (2628 +/- 578 kcal/d), with most participants (n = 270) requiring 9-13 MJ/d (2100-3100 kcal/d). The difference between predicted and observed intakes was highest at high estimated energy intakes, mainly because of high and probably incorrect estimates of the activity factor. Participants with lower energy intakes tended to need less adjustment of their energy intakes to maintain a stable weight than did participants with higher energy intakes. CONCLUSIONS: Weight stabilization is not affected by diet composition, sex, race, age, or baseline weight. Either the Harris-Benedict equation or the FAO/WHO equation can be used to estimate energy needs. Activity factors > 1.7 often lead to overestimation of energy needs.

Adolescent↗