Thermogenic Effect Of Food Research Articles

Duodeno-Jejunal Tube Placement in an Experimental Model of Obesity: Effects on Food Behaviour and Basal Energy Expenditure

Metabolic surgery can modulate weight as well as food intake and basal energy expenditure. In this study, we evaluate the effectiveness of duodenal exclusion by analysing anthropometric results, intake variations, food behaviour and calorimetric parameters. This is an experimental study with 8-week-old Sprague-Dawley male rats. The sequences used are as follows: Cafeteria diet for 3 weeks, followed by surgery and sacrifice at 4 weeks. Four experimental groups are as follows: two non-obese groups (n = 15; surgery = 10, sham = 5) and two obese groups by cafeteria diet (n = 15; surgery = 10, sham = 5). Surgery performed was duodenal exclusion with physical barrier. Weight, intake, glycaemia and basal energy expenditure by indirect calorimetry were monitored before and after surgery. Weight changes in groups that underwent intervention were significant. The reduction in calorie consumption after surgery was significant in the obese intervention group despite an increased standard feed consumption (161 ± 11 vs 139 ± 13 Kcal/day, p < 0.05; due to a lower consumption of cafeteria diet). In non-obese animals, changes were transient. Basal energy expenditure decreased in both intervention groups: 6.2 ± 0.5 vs 5.5 ± 0.4 Kcal/kg/h in non-obese animals and 5.6 ± 0.3 vs 4.7 ± 0.3 Kcal/kg/h in obese animals (p < 0.05). Duodeno-jejunal tube placement stops weight gain in obese and non-obese animals. In obese animals, there is an important qualitative change in appetite towards standard feed with a significant decrease in caloric intake. In non-obese animals, changes in quantitative intake are transient. This surgery decreases basal energy expenditure in obese animals. This may be attributed to an enhanced thermogenic effect of food and a slowing in the animal's weight gain.

Insulin resistance is not associated with thermogenic effect of a high-fat meal in obese children

In adults, insulin resistance may decrease the thermogenic effect of food, contributing to weight gain. We aimed to determine the effect of insulin resistance on energy expenditure in children with long-standing obesity. We hypothesized that thermogenic effect of food would decrease with increasing insulin resistance. Energy expenditure was measured using whole room indirect calorimetry in obese children 7 to 18 years old. Participants were fed a high-fat meal with energy content equal to 35% of measured resting energy expenditure. Thermogenic effect of food was measured for 180 minutes posttest meal and expressed as a percent of calories consumed. Body composition was assessed using whole-body dual-energy x-ray absorptiometry. Fasting glucose, insulin, and hemoglobin A1C were measured. Complete data were available for 25 children (median age, 12.1 years; 52% male). As expected, a significant decrease in resting energy expenditure was observed with increasing Tanner stage (P = .02 by Kruskal-Wallis test). Insulin sensitivity, as determined by homeostasis model assessment index equation, did not significantly affect resting energy expenditure (P = .3) or thermogenic effect of food (P = .7) after adjustment for Tanner stage. In conclusion, our study did not find an association between insulin resistance and energy expenditure in obese children.

Short Sleep Duration Is Associated with Higher Energy Intake and Expenditure among African-American and Non-Hispanic White Adults1,2

Habitual short sleep duration appears to increase the risk of obesity. The objective of this paper is to investigate the association of habitual sleep duration with objective measures of energy balance. One hundred twelve African-American and 111 non-Hispanic whites aged 21–69 y participated in a cross-sectional study of dietary assessment and biomarkers. Participants reported the mean number of hours per day spent sleeping over the past year. Short sleep duration was defined as ≤6 h/d of sleep. Energy intake (kilocalories) was objectively assessed using the 2-point doubly labeled water technique to determine total energy expenditure, which is approximately equal to energy intake. Physical activity energy expenditure (kilocalories) was estimated as total energy expenditure minus each participant’s calculated basal metabolic rate and the thermogenic effect of food. Compared with participants who slept ≤6 h, individuals who slept 8 h were significantly less likely to be obese (OR: 0.33; 95% CI: 0.14, 0.79). However, this association was not linear across 6–9 h of sleep (P-trend = 0.16). There was an inverse association between sleep and energy intake (P-trend = 0.07): compared with ≤6 h/d, adults who reported ≥9 h sleep consumed 178 fewer kcal/d. There was also an inverse association between sleep and physical activity (P-trend = 0.05): compared with ≤6 h/d of sleep, adults who reported 9 h of usual sleep expended 113 fewer kcal/d in physical activity. These data indicate that, compared with longer sleep duration, adults who report habitual short sleep duration have somewhat higher physical activity energy expenditure but considerably higher energy intake. Habitual short sleep duration appears to be 1 of the facets of modern life leading to a mismatch between energy intake and physical activity.

Predicted vs. Actual Resting Energy Expenditure and Activity Coefficients: Post-Gastric Bypass, Lean and Obese Women

Total Energy Expenditure (TEE) and energy requirements are commonly estimated from equations predicting Resting Energy Expenditure (REE) multiplied by a Physical Activity (PA) coefficient that accounts for both PA energy expenditure and the thermogenic effect of food. PA coefficients based on PA self-reports are a potential source of error that has not been evaluated. Therefore, in this study we compared: 1) the Harris-Benedict (HB), Mifflin-St. Jeor (MSJ), and the Food and Agriculture Organization/World Health Organization/United Nations University (FAO/WHO/UNU) REE equations with REE measured (REE-m) with indirect calorimetry; 2) PA coefficients determined with PA self-reports vs. objectively assessed PA; and 3) TEE estimates in post-Gastric Bypass (GB = 13), lean (LE = 7), and obese (OB = 12) women. REE was measured in the morning after an overnight fast with participants resting supine for 30 min. Self-reported PA was evaluated with a questionnaire and objectively measured with accelerometers worn for 5-7 days. Nutritional intake was evaluated with a food frequency questionnaire. Anthropometry included DEXA, and abdominal CT scans. Eligible GB had surgery ≥ 12 months before the study, and had ≥ 10 kg of body weight loss. All participants were 18-45 years of age, able to engage in ambulatory activities, and not taking part in exercise training programs. One-way ANOVA was used to detect differences in REE and TEE. Accuracy of REE prediction equations were determined by cases within 10% of REE-m, and agreement analyses. REE predictions were not different than REE-m, but agreements were better with HB and MSJ, particularly in the GB and LE groups. Discrepancies in the PA coefficients determined with self-report vs. objectively assessed PA resulted in TEE overestimates (approximately 200-300 Kcal/day) using HB and MSJ equations. FAO/WHO/UNU overestimated TEE in all groups regardless of the PA assessment method (approximately 300-900 kcal/day). These results suggest that: 1) HB and MSJ equations are good predictors of REE among GB and LE, but not among OB women, 2) PA coefficients used to estimate TEE must be determined with objective PA assessment, and 3) TEE estimates using PA coefficients with the FAO/WHO/UNU equation must be used with caution.

Energy expenditure in obese children with pseudohypoparathyroidism type 1a

ContextPatients with pseudohypoparathyroidism type 1a (PHP-1a) develop early-onset obesity. The abnormality in energy expenditure and/or energy intake responsible for this weight gain is unknown.ObjectiveThe aim of this study was to evaluate energy expenditure in children with PHP-1a compared with obese controls.PatientsWe studied 6 obese females with PHP-1a and 17 obese female controls. Patients were recruited from a single academic center.MeasurementsResting energy expenditure and thermogenic effect of a high fat meal were measured using whole room indirect calorimetry. Body composition was assessed using whole body dual energy x-ray absorptiometry. Fasting glucose, insulin and hemoglobin A1C were measured.ResultsChildren with PHP-1a had decreased resting energy expenditure compared with obese controls (P <0.01). After adjustment for fat free mass, the PHP-1a group’s resting energy expenditure was 346.4 kcals/day less than obese controls (95% CI [−585.5 to −106.9], P <0.01). The thermogenic effect of food, expressed as percent increase in postprandial energy expenditure over resting energy expenditure, was lower in PHP-1a patients than obese controls but did not reach statistical significance (absolute reduction of 5.9%, 95% CI [−12.2% to 0.3%], P = 0.06).ConclusionsOur data indicate that children with PHP-1a have decreased resting energy expenditure compared with obese controls and that may contribute to the development of obesity in these children. These patients may also have abnormal diet-induced thermogenesis in response to a high fat meal. Understanding the causes of obesity in PHP-1a may allow for targeted nutritional or pharmacologic treatments in the future.

Increased resting energy expenditure in children with attention-deficit-hyperactivity disorder.

Attention Deficit Hyperactivity Disorder (ADHD) is one of the most frequently reported neuropsychiatric disorders in childhood. However, there is limited data on the biological basis for this disorder. Disturbances in neurotransmitters have been suggested to play a pathophysiologic role. Phenotypically an increased prevalence of obesity has been reported. To investigate resting energy expenditure (REE) and diet-induced thermogenesis in stimulant medication-naïve children with ADHD. Case control study of 12 pre-pubertal boys with ADHD of the hyperactive-impulsive type and 12 control boys without ADHD. Anthropometric testing and indirect calorimetry were performed before and after a standardized meal. REE and thermogenesis were measured in each subject at 2 time points. In an independent group of 60 boys with ADHD, BMI standard deviation scores (BMI-SDS) were compared to age-adapted reference values. REE was on average 6.5 kcal/kg fat free mass/day higher in the ADHD compared to the control group (p<0.01). In contrast, the thermogenic effect of food was not different between the two groups (average increase by 16%, p=n.s.). The repeat measurements, an average of 5±1 months apart, were highly reproducible in all subjects. Age and restlessness did not explain the differences in REE. Boys with ADHD had similar BMI-SDS values (mean BMI-SDS -0.10±0.98) as reference groups. REE, in contrast to diet-induced thermogenesis, is higher in medication-naïve boys with ADHD. The normal BMI levels suggest increased energy intake in these children.

Resting Metabolic Rate and Thermogenic Effect of Food in Vegetarian Diets Compared with Mediterranean Diets

The purpose of our work is to compare the resting metabolic rate (RMR) and thermogenic effect of food (TEF) in a group of vegetarians and a group of subjects consuming a Mediterranean diet. The composition of the diets was similar. Thirty-two subjects were studied: 16 vegetarians (age 34 ± 9 years, BMI 21 ± 2) and 16 omnivors (age 30 ± 5 years, BMI 22 ± 3). All were in excellent general health. Each subject consumed a dish of pasta (100 g) and bread (30 g) after RMR had been measured. TEF was measured over the next 3 h and calculated as the incremental area above RMR. Energy (vegetarians and omnivors 7,727 ± 3,516 vs 8,970 ± 2,273 kJ/day, respectively) and carbohydrate (vegetarians and omnivors 285.1 ± 141.3 vs. 300.1 ± 74 g/day, respectively) intakes of the 2 groups were similar. The vegetarian group consumed a higher quantity of fiber (30.5 ± 16.7 vs. 16.5 ± 7.9) and a lower amount of protein (44.9 ± 18.3 vs. 70.1 ± 14.9) than the omnivorous group. No significant differences were observed in RMR (4.23 ± 0.96 vs. 4.06 ± 0.54 kJ/min) and TEF (0.50 ± 0.25 vs. 0.38 ± 0.25 ΔkJ/min) between the groups. Results did not change after correcting for weight, age and gender. Our study failed to show any significant differences in RMR and TEF between vegetarians and subjects consuming a Mediterranean diet. We conclude that vegetarianism per se is not accompanied by a difference in RMR and TEF when the carbohydrate content of the diet is similar to a control group of nonvegetarians.

Energy Balance in Stable Malnourished Patients with Chronic Obstructive Pulmonary Disease

We have measured caloric intake, energy expenditure, and the thermogenic effect of food in ten patients with stable COPD who had a history of involuntary weight loss over several years and were malnourished (< 85 percent ideal body weight). Each patient completed a 7-day food record. Indirect calorimetry was performed in the resting postabsorptive state. After placement of a nasoenteric tube, patients were randomly assigned to be refed or sham-fed (mean +/- SD, 16 +/- 3 days), following which, metabolic measurements were repeated. Indirect calorimetry was also performed before and after a large meal in each patient. Home caloric intake was 135 +/- 23 percent of resting energy expenditure. Resting energy expenditure was 94 +/- 16 percent of that predicted by the Harris-Benedict equation and did not change significantly during inpatient refeeding. Refeeding resulted in weight gain (2.4 +/- 1.9 kg, p < 0.02). A large meal caused substantial increases in energy expenditure (24 +/- 18 percent), carbon dioxide production (39 +/- 18 percent), and oxygen consumption (23 +/- 16 percent). We conclude that stable malnourished COPD patients consume adequate calories to meet average energy requirements and are not hypermetabolic. Inpatient refeeding by nocturnal nasoenteric infusion is well tolerated and results in weight gain, but the thermogenic effect of a large meal poses a considerable metabolic and ventilatory load that could precipitate acute respiratory failure.

The thermogenic and metabolic effects of food in liver cirrhosis: Consequences on the storage of nutrients and the hormonal counterregulatory response

The thermogenic effect of food and the rates of oxidation and storage of nutrients were evaluated by indirect calorimetry in 10 cirrhotic patients and seven normal controls for a 6-hour period, after they had consumed a standard meal supplying 15 kcal/kg body weight with 15%, 30%, and 55% protein, fat, and carbohydrate calories, respectively. Although the thermogenic response to food was not significantly lower in patients than in controls ( 51.6 ± 13.5 v 72.2 ± 8.8 kcal 6 h ), patients exhibited a delayed and blunted increment of energy expenditure after the meal intake ( P < .025). The greater part of the glucose load was oxidized in patients (70.2 ± 3.9% v 50.4 ± 3.9% in controls; P < .01), suggesting a defective glucose storage as glycogen. This result could be related to insulin resistance, which was evidenced by a large increase in glucose and insulin levels after the meal intake in patients ( P ± .001). Conversely, lipid oxidation was sharply reduced and de novo lipogenesis occurred in patients, so that the rate of lipid storage was increased. The profiles of circulating levels of catecholamines, thyroid hormones (free thyroxine [FT 4] and triiodothyronine [T 3]), and glucagon were assayed during the test. Norepinephrine and glucagon levels remained higher in patients throughout the test ( P < .001), whereas thyroid hormones stayed in the same range in the two groups. After an initial increase, glucose levels decreased sharply, inducing an activation of counterregulatory hormones, glucagon, and notably, epinephrine, for which the increment was correlated with the decrease of glucose ( r = −.917; P < .001). The involvement of counterregulatory hormones led to an increase of lipid oxidation; this may explain the preferential use of fat as a fuel substrate that was observed in these patients at fast.

Polyunsaturated: Saturated ratio of diet fat influences energy substrate utilization in the human

In order to examine the effect of dietary long chain fatty acid composition on energy substrate utilization, basal metabolism rate (BMR) and the thermogenic effect of food (TEF) were measured in eight subjects consuming diets varying only in diet fat polyunsaturated: saturated (P:S) ratio. Subjects consumed the low P:S (0.241 ± 0.02) and high P:S (1.65 ± 0.28) ratio diets for seven days using a crossover design. Fat and carbohydrate oxidation during BMT and TEF over 230 minutes after a breakfast meal were determined on days 1 and 7 of each diet period using open circuit respiratory gas exchange. On day 7, BMR respiratory quotient was reduced ( P < .05) for the low P:S (0.826 ± 0.005) compared with high P:S (0.853 ± 0.014) ratio diet, resulting in an increased basal fat oxidation rate with low P:S (0.074 ± 0.006 g/min) compared with high P:S (0.059 ± 0.008 g/min) ratio diet feeding. The cumulative contribution of fat oxidation to TEF on day 7 was lower ( P < .01) for the low P:S (1.35 ± 1.6 g) compared with high P:S (6.49 ± 0.8 g) ratio diets. This was paralleled by opposite differences ( P < .05) in the contribution of carbohydrate oxidation to TEF (21.0 ± 3.0 g and 13.1 ± 3.4 g, respectively, for each diet treatment). On day 1 in subjects switching from either home and alternate test diets, and on day 7, caloric expenditure of TEF after low P:S was not statistically lower compared to the high P:S ratio diet. On day 1 subjects switching from the alternate diet showed a significant decrease ( P < .05) in total fat oxidation of TEF after low P:S (13.5 ± 2.4 g) compared to high P:S (17.9 ± 1.6 g) ratio diets. These findings suggest that the long chain fatty acid composition of dietary fat modulates the oxidation of fat and carbohydrate acutely after meal feeding and after chronic feeding.

Thermogenic effect of food in physically well-trained elderly men.

Basal metabolic rate (BMR) and the thermogenic effect of food (TEF) after a liquid mixed meal of 2092 kJ (500 kcal) were examined in physically well-trained, elderly men in comparison with sedentary weight- and age-matched controls. BMR tended to be higher and TEF was significantly higher in the physically well-trained men than in the controls. No certain differences were found in plasma thyroid hormones or catecholamines. BMR correlated with whole body potassium while TEF did not. The tendency to elevated BMR in the well-trained men might therefore be due to their greater muscle mass. The elevated TEF, however, probably has other causes and might be associated with the elevated catecholamine sensitivity associated with the physically trained condition.