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... In table 2 we summarize several dietary ingredients that are under research because of their thermogenic potential (induce considerable changes in energy expenditure) and safety if consumed in recommended doses; nonetheless, it is necessary to clarify that they are not able to solve obesity/overweight by their own but might provide some advantages in long term treatments. Green Tea (Camelia sinensis) 6-8 mg of Green Tea with 50% of Epigalocatechin-3-gallate (EGCG) per kg of body massThermogenic and antioxidant properties due to polyphenols and catechinsSeems to increase fat oxidation under resting and post-exerciseProlongs catecholamine-induced lipolysis during exercise probably by inhibition of catechol-o-methyltransferase (COMT)Xanthine derivatives can act as phosphodiesterase (PDE) inhibitors  Chilli Pepper (Capsicum) 2-10 mg Capsaicinoids per kg of body massThermogenic and anti-obesity potentialIncreases resting energy expenditureActivates sympathetic nervous system and BAT via Transient Receptor Potential Vanilloid 1 (TRPV1) and probably Melastatin 8 Channel (TRPM8)Stimulates lypolisis through lipases activation  Anhydrous Caffeine 2-4 mg Caffeine (1,3,7-trimethylxanthine) per kg of body mass ...
Obesity is a multifactorial disease characterized by an expansion of lipid storage in the form of triacylglycerides in adipose tissue (mainly in White Adipose Tissue, WAT). According to WHO, around 650 million of adults were obese in 2016. The fact sheet literally states "…overweight and obesity are linked to more deaths worldwide than underweight. Globally there are more people who are obese than underweight-this occurs in every region except parts of sub-Saharan Africa and Asia". Thus, this pathology must be addressed from an ana-tomic, neurophysiologic, psycho-social, metabolic and genetic point of view, since medical staff would seize an integral approach during individual treatment in each patient [1,2]. Abstract Currently, obesity is an important public health problem in the world, which is considered as a multifactorial and chronic disease, with many situations conditioning the development of this pathology. Therefore, obesity is the result of the interaction between lifestyle (excessive of energy-dense food intake and sedentariness) and genetic predisposition. Some genetic variations have been linked to obese phenotype, affecting metabolic pathways related to energy production at the mitochondrial level, such as mutations in uncoupling proteins (UCPs). Besides of updating key concepts about thermogenesis and its relationship to obesity, we report experimental results in a couple of Venezuelan obese subjects (among n = 95 analyzed individuals) with the pathogenic polymorphism in exon 4 of the UCP3 gene (C→T mutation at −427 bp), named rs104894319. UCPs are proteins located in the mitochondrial inner membrane that carry out an important role in adaptive thermogenesis, a process that takes place during electron transport chain and oxidative phosphorylation when ATP is produced, but instead of using protons (H +) to generate the electrochemical gradient in ATP synthase, the UCPs redirect H + to dissipate that energy as heat. In fact, high capacity to produce heat of brown adipose tissue (BAT) is due to this uncoupling process, as well as during browning process that may suffer white adipose tissue (WAT) in the conversion to beige/brite adipose tissue. This might result after adaptation mechanisms from nutritional intervention, supplementation or physical exercise practice, which in turn may be used as a complementary strategy to deal with obesity nowadays.
Background and aims: A personal indirect calorimeter allows everyone to assess resting and
non-resting energy expenditure, thus enabling accurate determination of a person’s total calorie need
for weight management and fitness. The aim of this study is to compare the performance of a new
personal metabolic rate tracker based on indirect calorimetry, Breezing®, with the Douglas bag method,
the gold standard method for energy expenditure (EE) measurement.
Methods: Energy expenditures (EE) at rest and during activities, and respiratory quotient (RQ)
were measured for 12 healthy subjects, including 7 males and 5 females under different living conditions.
A total of 314 measurements were performed with Breezing®, and the results were compared with those
by the Douglas bag method.
Results: R-squared correlation coefficients (R2) between the data obtained with Breezing® and the Douglas bag method were 0.9976, 0.9986, 0.9981, and 0.9980, for VO2, VCO2, EE, and RQ, respectively.
Conclusions: The EE and RQ values determined by Breezing® are in good agreement with those
by the Douglas bag method.
In the present investigation we compared blood epinephrine (EPI), norepinephrine (NE), free fatty acids (FFA) and glycerol concentrations in response to a capsaicinoid supplement or placebo in healthy adults before and after acute exercise.
Twenty subjects ingested a placebo or supplement (Capsimax, OmniActive Health Technologies; 2 mg capsaicinoids in a microencapsulated matrix) with one week separating conditions. Fasting blood samples were collected during each visit; 30 minutes following a rest period and before placebo or supplement intake (Pre); 2 hours post intake (2 hr); one minute following the cessation of 30 minutes of exercise performed at 65% of maximal heart rate reserve (2.5 hr); 90 minutes following the cessation of exercise (4 hr). Heart rate (HR), systolic (SBP) and diastolic (DBP) blood pressure were recorded at all times.
A time effect was noted for HR, SBP, and DBP (p < 0.05), with HR and SBP higher at 2.5 hr compared to Pre (due to exercise) and DBP lower at 2.5 hr compared to Pre. No interaction or condition effects were noted for EPI, NE, FFA, or glycerol (p > 0.05). However, a time effect was noted for all variables (p < 0.0001), with values higher than Pre at 2.5 hr for EPI and glycerol, at 2 hr and 2.5 hours for FFA, and at 2 hr, 2.5 hr, and 4 hr for NE (p < 0.05). In terms of percent change from Pre, glycerol was higher with Capsimax than for placebo at 4 hr (p = 0.011) and FFA was higher with Capsimax than for placebo at 2 hr (p = 0.025) and at 2.5 hr (p = 0.015).
Ingestion of low dose (2 mg) Capsimax was associated with an increase in blood FFA and glycerol at selected times post ingestion, as compared to placebo. However, Capsimax had no differing effect on EPI or NE compared to placebo. Lastly, no difference was noted in HR, SBP, or DBP between placebo and Capsimax.
We investigated the effects of dietary red pepper on the energy metabolism in male subjects. In the first experiment, after having a standardized dinner on the previous evening, the subjects consumed a breakfast (650 kcal) either with or without 10 g of red pepper. For 150 min after the meal, they took a rest and their expired gas was collected. During the initial 30 min after the meal, the energy expenditure tended to be higher in the red-pepper diet period than in the control diet period. For the remaining 120 min, no difference in the energy expenditure was found between the red-pepper diet period and the control diet period. However the carbohydrate oxidation was significantly higher in the red-pepper diet period than in the control diet period while the lipid oxidation was lower in the red-pepper diet period than in the control diet period for 150 min after the meal. In the second experiment, the subjects consumed a breakfast with 10 g of red pepper after an oral administration of propranolol or a placebo. The propranolol abolished the increase in energy expenditure during the initial 30 min due to the meal containing red pepper. For the remaining 120 min, no difference in energy expenditure was found between the propranolol period and the placebo period. These results suggest than an increase in the energy expenditure after the meal containing red pepper appeared only immediately after the meal ingestion and a red-pepper diet increases the carbohydrate oxidation without increasing total energy expenditure for 150 min after the meal. And an increase in the energy expenditure immediately after the meal containing red pepper is considered to be caused by beta-adrenergic stimulation.
The effects of red pepper and caffeine ingestion on energy and macronutrient balances were examined in eight Caucasian male subjects. All subjects participated in two randomly assigned conditions: control and experimental (red pepper and caffeine). After ingesting a standardized breakfast, subjects ate three meals ad libitum (lunch, dinner and breakfast) and snacks which were served approximately 2 h after the lunch and dinner over a 24 h period. Two appetizers with or without 3 g red pepper) were given before lunch and dinner, and a drink (decaffeinated coffee with or without 200 mg caffeine) was served at all meals and snacks except for the after-dinner snack. It is also important to note that on the experimental day, 8.6 and 7.2 g red pepper were also added to lunch and dinner respectively. Red pepper and caffeine consumption significantly reduced the cumulative ad libitum energy intake and increased energy expenditure. The mean difference in energy balance between both conditions was 4000 kJ/d. Moreover, the power spectral analysis of heart rate suggested that this effect of red pepper was associated with an increase in sympathetic:parasympathetic nervous system activity ratio. These results indicate that the consumption of red pepper and caffeine can induce a considerable change in energy balance when individuals are given free access to foods.
Type 2 diabetes mellitus is increasingly common, primarily because of increases in the prevalence of a sedentary lifestyle and obesity. Whether type 2 diabetes can be prevented by interventions that affect the lifestyles of subjects at high risk for the disease is not known.
We randomly assigned 522 middle-aged, overweight subjects (172 men and 350 women; mean age, 55 years; mean body-mass index [weight in kilograms divided by the square of the height in meters], 31) with impaired glucose tolerance to either the intervention group or the control group. Each subject in the intervention group received individualized counseling aimed at reducing weight, total intake of fat, and intake of saturated fat and increasing intake of fiber and physical activity. An oral glucose-tolerance test was performed annually; the diagnosis of diabetes was confirmed by a second test. The mean duration of follow-up was 3.2 years.
The mean (+/-SD) amount of weight lost between base line and the end of year 1 was 4.2+/-5.1 kg in the intervention group and 0.8+/-3.7 kg in the control group; the net loss by the end of year 2 was 3.5+/-5.5 kg in the intervention group and 0.8+/-4.4 kg in the control group (P<0.001 for both comparisons between the groups). The cumulative incidence of diabetes after four years was 11 percent (95 percent confidence interval, 6 to 15 percent) in the intervention group and 23 percent (95 percent confidence interval, 17 to 29 percent) in the control group. During the trial, the risk of diabetes was reduced by 58 percent (P<0.001) in the intervention group. The reduction in the incidence of diabetes was directly associated with changes in lifestyle.
Type 2 diabetes can be prevented by changes in the lifestyles of high-risk subjects.
To assess the validity and reliability of a hand-held indirect calorimeter.
Resting metabolic rate (RMR) was measured on two separate mornings.
A heterogeneous sample of 41 healthy adults.
RMR using both a metabolic cart (Sensormedics 2900, SM-2900) and a hand-held indirect calorimeter (BodyGem, BG).
There were no trial-to-trial differences in RMR measured by the BG (6756+/-163 vs 6697+/-163 kJ/day) or the SM-2900 (6400+/-163 vs 6396+/-167 kJ/day). RMR measured by the BG was significantly higher than that measured by the SM-2900 during both trials. In a sample of 10 subjects, the energy cost of holding the BG in position was determined to be (0.17+/-0.04 kJ/min, or 255+/-84 kJ/day). After applying this adjustment, the differences between systems were no longer significant during trial 1 (mean difference=101+/-67 kJ/day) or trial 2 (46+/-75 kJ/day). In overweight and obese individuals, RMR measured by the BodyGem was more accurate than that estimated by the Harris-Benedict equations.
The BodyGem provides valid and reliable measurements of RMR. The BodyGem produces significantly higher values than the Sensor Medics 2900 indirect calorimeter, with the increase largely due to an increased energy demand required to hold the BG in position.
To compare, in patients with cancer and in healthy subjects, measured resting energy expenditure (REE) from traditional indirect calorimetry to a new portable device (MedGem) and predicted REE.
Cross-sectional clinical validation study.
Private radiation oncology centre, Brisbane, Australia.
Cancer patients (n = 18) and healthy subjects (n = 17) aged 37-86 y, with body mass indices ranging from 18 to 42 kg/m(2).
Oxygen consumption (VO(2)) and REE were measured by VMax229 (VM) and MedGem (MG) indirect calorimeters in random order after a 12-h fast and 30-min rest. REE was also calculated from the MG without adjustment for nitrogen excretion (MGN) and estimated from Harris-Benedict prediction equations. Data were analysed using the Bland and Altman approach, based on a clinically acceptable difference between methods of 5%.
The mean bias (MGN-VM) was 10% and limits of agreement were -42 to 21% for cancer patients; mean bias -5% with limits of -45 to 35% for healthy subjects. Less than half of the cancer patients (n = 7, 46.7%) and only a third (n = 5, 33.3%) of healthy subjects had measured REE by MGN within clinically acceptable limits of VM. Predicted REE showed a mean bias (HB-VM) of -5% for cancer patients and 4% for healthy subjects, with limits of agreement of -30 to 20% and -27 to 34%, respectively.
Limits of agreement for the MG and Harris Benedict equations compared to traditional indirect calorimetry were similar but wide, indicating poor clinical accuracy for determining the REE of individual cancer patients and healthy subjects.
Objective: Capsaicinoids are a group of chemicals naturally occurring in chilli peppers with bioactive properties that may help to support weight management. The aim of the present study was to conduct a meta-analysis investigating the potential effects of capsaicinoids on energy intake, to clarify previous observations and form evidence-based conclusions about possible weight management roles. Methods: Medical databases (Medline, Web of Knowledge and Scopus) were systematically searched for papers. Search terms were: ‘capsaicin*’ or ‘red pepper’ or ‘chilli*’ or ‘chili*’ with ’satiety’ or ‘energy intake’. Of the seventy-four clinical trials identified, 10 were included, 8 of which provided results suitable to be combined in analysis (191 participants). From the studies, 19 effect sizes were extracted and analysed using MIX meta-analysis software. Results: Data analysis showed that capsaicinoid ingestion prior to a meal reduced ad libitum energy intake by 309.9 kJ (74.0 kcal) p < 0.001 during the meal. Results, however, should be viewed with some caution as heterogeneity was high (I2 = 75.7%). Study findings suggest a minimum dose of 2 mg of capsaicinoids is needed to contribute to reductions in ad libitum energy intake, which appears to be attributed to an altered preference for carbohydrate-rich foods over foods with a higher fat content. Conclusions: Meta-anlysis findings suggest that daily consumption of capsaicinoids may contribute to weight management through reductions in energy intake. Subsequently, there may be potential for capsaicinoids to be used as long-term, natural weight-loss aids. Further long-term randomised trials are now needed to investigate these effects.
Capsaicinoids are a group of chemicals found in chilli peppers, with bioactive properties. The purpose of this study is to systematically review research investigating the potential benefits capsaicinoid compounds may have in relation to weight management. Medical databases were searched and 90 trials found, 20 of which were selected for inclusion, involving 563 participants. Three main areas of potential benefit for weight management were found: (1) increased energy expenditure; (2) increased lipid oxidation and (3) reduced appetite. Trial duration, dosage and sized varied, though trials were generally of high quality with a low risk of bias. It was observed that consumption of capsaicinoids increases energy expenditure by approximately 50 kcal/day, and that this would produce clinically significant levels of weight loss in 1-2 years. It was also observed that regular consumption significantly reduced abdominal adipose tissue levels and reduced appetite and energy intake. The mechanism of action is not presently fully understood, although it is well accepted much of the effects are caused by stimulation of the TRPV1 receptor. While capsaicinoids are not a magic bullet for weight loss, the evidence is that they could play a beneficial role, as part of a weight management program.
Indirect calorimetry is a noninvasive and reliable means of determining resting metabolic rate in humans. Barriers to obtaining an accurate measure of resting metabolic rate (RMR) in hospitalized patients include the expense and the requirement of technical expertise for maintenance.
A literature search on handheld calorimeters was conducted using PubMed and OVID. The search resulted in a total of 54 published articles; 23 of these specifically are about handheld calorimeter devices.
Results from a handheld calorimeter were similar to those obtained from metabolic cart studies. The Douglas bag method compared with the MedGem indicated a significant agreement (P = .286). The handheld device was compared with metabolic carts in 9 studies with mixed results. The predictive equations (Harris-Benedict, Mifflin-St Jeor, and FAO/WHO equations) over- and underestimated RMR compared with the MedGem. The Harris-Benedict equation overestimated the RMR by 3%-11%, the Mifflin-St Jeor equation overestimated the RMR by 1%, and the FAO/WHO equation overestimated RMR by 12%.
The present study examines the validity and reliability of handheld calorimeters for measuring resting energy expenditure based on published literature. Handheld calorimeters are more accurate than predictive equations based on gender, age, and ethnicity for determining resting metabolic rate and are therefore a viable alternative for clinical evaluation of the hospitalized patient.
Capsaicin, a spicy component of hot peppers, has been shown to improve inflammatory disease and obesity. In this study, we tested the hypothesis that the anti-inflammatory activity of capsaicin can be used to improve free fatty acid (FFA)-induced inflammation by reducing gene expression of macrophage inflammatory protein 1 (MIP-1) and interleukin 8 (IL-8) in THP-1 (human acute monocytic leukemia cell) macrophages. To investigate whether capsaicin ameliorates palmitate-induced MIP-1 and IL-8 gene expressions, we treated THP-1 cells with palmitate in the presence or absence of capsaicin and measured MIP-1 and IL-8 by real-time polymerase chain reaction. To elucidate the mechanism by which capsaicin effects on palmitate-induced MIP-1 and IL-8 gene expressions, we performed immunoblotting with stress kinase-related antibodies and measured palmitate oxidation and palmitate oxidation-related gene expression. Palmitate and stearate but not the unsaturated FFA oleate significantly increased MIP-1 and IL-8 expressions in THP-1 macrophages. Treatment with capsaicin or FFA oxidation stimulators inhibited palmitate-induced MIP-1 and IL-8 expressions in THP-1 macrophages. Capsaicin increased the gene expression of carnitine palmitoyltransferase 1 and the β-oxidation of palmitate. Furthermore, capsaicin significantly reduced palmitate-stimulated activation of c-Jun N-terminal kinase, c-Jun, and p38. Our data suggest that the attenuation of palmitate-induced MIP-1 and IL-8 gene expressions by capsaicin is associated with reduced activation of c-Jun N-terminal kinase, c-Jun, and p38 and preserved β-oxidation activity.
We determined whether nine common herbs (basil, chili, cilantro, dill, garlic, ginger, lemongrass, oregano, and parsley) and one herb mixture (Italian Herbs) retain the antioxidant capacity (AC) and content of phenolics and characteristic marker compounds during processing to dry and paste forms. Oregano exhibited the highest AC among the herbs tested in dry and fresh forms. Compared with fresh herbs, the AC in dry form was decreased in garlic, chili, dill, oregano and parsley and paste form of oregano and basil. With the exception of dried garlic and lemongrass in fresh and paste form, all herbs in dry, paste, and fresh form contained significant AC. The AC was correlated significantly to the total phenolic content in both dry and fresh form. However, there was no significant correlation between the AC and the concentration of chemical marker compounds. In summary, processed herbs contribute significant amounts of AC to the diet.
To investigate the effects of capsaicin (CAP) on proliferation of bladder cancer T24 cells in vitro as well as on xenografts in nude mice in vivo.
T24 cells were assessed for cell viability and apoptosis by 3-(4, 5-dimethylthiazol-2-yl)-3, 5-diphenyltetrazolium bromide assay and flow cytometry analysis after incubation with different concentrations of CAP. To uncover the mechanism by which CAP affected the viability of T24 cells, intracellular production of reactive oxygen species (ROS) and mitochondrial membrane potential were assessed. To study the in vivo effects of CAP, T24 cells were grown as xenografts in nude mice and CAP (5 mg/kg by wt) was subcutaneously injected into nude mice with bladder tumors.
CAP decreased the viability of T24 cells in a dose-dependent manner without marked apoptosis. CAP induced ROS production and mitochondrial membrane depolarization, thereby inducing cell death, not apoptosis, in T24 cells at a concentration of 100 microM or higher. Furthermore, these effects of CAP could be reversed by capsazepine, the antagonist of transient receptor potential vanilloid type 1 channel. In vivo experiment showed that CAP significantly slowed the growth of T24 bladder cancer xenografts as measured by size (661.80 +/- 62.03 vs 567.02 +/- 43.94 mm(3); P <.01).
CAP mediates cell death in T24 cells through calcium entry-dependent ROS production and mitochondrial depolarization, and it may have a role in the management of bladder cancer.
Obesity is a major health problem in developed countries and a growing one in the developing world. It increases the risk of diabetes, heart disease, fatty liver and some forms of cancer. A better understanding of the biological basis of obesity should aid its prevention and treatment.
The purpose of this study was to identify and describe how adults with diabetes in a weight control study attempted to make life-style behavioral changes. All subjects had non-insulin-dependent diabetes mellitus (NIDDM) and were 20% to 50% overweight. Data were drawn from narrative responses given by 28 clients to open-ended questions regarding behavioral change. Questions were asked as part of a 16-week life-style behavioral change program for weight control. A systematic analysis of content was used to generate six categories of responses depicting the life-style behavioral change process. The process, as described by these clients, is: Starting point; Introspection; Why change; Mental preparation; Plans, progress, and continuation; and Helps and hindrances.
Current interest in the role of functional foods in weight control has focused on plant ingredients capable of interfering with the sympathoadrenal system.
We investigated whether a green tea extract, by virtue of its high content of caffeine and catechin polyphenols, could increase 24-h energy expenditure (EE) and fat oxidation in humans.
Twenty-four-hour EE, the respiratory quotient (RQ), and the urinary excretion of nitrogen and catecholamines were measured in a respiratory chamber in 10 healthy men. On 3 separate occasions, subjects were randomly assigned among 3 treatments: green tea extract (50 mg caffeine and 90 mg epigallocatechin gallate), caffeine (50 mg), and placebo, which they ingested at breakfast, lunch, and dinner.
Relative to placebo, treatment with the green tea extract resulted in a significant increase in 24-h EE (4%; P < 0.01) and a significant decrease in 24-h RQ (from 0.88 to 0.85; P < 0.001) without any change in urinary nitrogen. Twenty-four-hour urinary norepinephrine excretion was higher during treatment with the green tea extract than with the placebo (40%, P < 0.05). Treatment with caffeine in amounts equivalent to those found in the green tea extract had no effect on EE and RQ nor on urinary nitrogen or catecholamines.
Green tea has thermogenic properties and promotes fat oxidation beyond that explained by its caffeine content per se. The green tea extract may play a role in the control of body composition via sympathetic activation of thermogenesis, fat oxidation, or both.
The prevalence of obesity is increasing globally, with nearly half a billion of the world's population now considered to be overweight or obese. The obesity epidemic is related both to dietary factors and to an increasingly sedentary lifestyle. Obesity has significant co-morbidities and these are associated with substantial health care and social costs. Of particular concern is the fact that obesity is increasing among children and adolescents. National health policymakers must take action to deal with the obesity problem. Prevention should be the primary target, but it is also important to develop strategies to treat those already affected with obesity.
The increased rate of obesity in the past decade is caused by a larger rate of energy input than energy expenditure. But this simple explanation belies the complexity of the possible solutions: Education about obesity needs to improve for both the medical community and the public. Successful treatment will require reforms of medical practice as well as more research to facilitate the development of new drugs.
Decreased appetite and increased energy expenditure after oral consumption of red pepper has been shown.
The aim of the present study was to assess the relative oral and gastrointestinal contribution to capsaicin-induced satiety and its effects on food intake or macronutrient selection.
For 24 subjects (12 men and 12 women; age: 35+/-10 y; BMI: 25.0+/-2.4 kg/m2; range 20-30), 16 h food intake was assessed four times during 2 consecutive days by offering macronutrient-specific buffets and boxes with snacks, in our laboratory restaurant. At 30 min before each meal, 0.9 g red pepper (0.25% capsaicin; 80,000 Scoville Thermal Units) or a placebo was offered in either tomato juice or in two capsules that were swallowed with tomato juice. Hunger and satiety were recorded using Visual Analogue Scales.
Average daily energy intake in the placebo condition was 11.5+/-1.0 MJ/d for the men and 9.4+/-0.8 MJ/d for the women. After capsaicin capsules, energy intake was 10.4+/-0.6 and 8.3+/-0.5 MJ/d (P<0.01); after capsaicin in tomato juice, it was 9.9+/-0.7 and 7.9+/-0.5 MJ/d, respectively (compared to placebo: P<0.001; compared to capsaicin in capsules: P<0.05). En % from carbohydrate/protein/fat (C/P/F): changed from 46+/-3/15+/-1/39+/-2 to 52+/-4/15+/-1/33+/-2 en% (P<0.01) in the men, and from 48+/-4/14+/-2/38+/-3 to 42+/-4/14+/-2/32+/-3 en% (P<0.01) in the women, in both capsaicin conditions. Satiety (area under the curve) increased from 689 to 757 mmh in the men and from 712 to 806 mmh in the women, both (P<0.01). Only in the oral exposure condition was the reduction in energy intake and the increase in satiety related to perceived spiciness.
In the short term, both oral and gastrointestinal exposure to capsaicin increased satiety and reduced energy and fat intake; the stronger reduction with oral exposure suggests a sensory effect of capsaicin.
To test whether consumption of a beverage containing active ingredients will increase 24-hour energy metabolism in healthy, young, lean individuals. RESEARCH METHOD AND PROCEDURES: Thirty-one male and female subjects consumed 3 x 250-mL servings of a beverage containing green tea catechins, caffeine, and calcium for 3 days in a single-center, double-blind, placebo-controlled, cross-over design study. On the 3rd day, 23-hour energy metabolism, extrapolated to 24-hour, was measured in a calorimeter chamber. Blood pressure and heart rate were measured, and total day and night urines were analyzed for urea and catecholamine excretion.
Twenty-four-hour energy expenditure (EE) and 24-hour fat oxidation were lower in women than in men (p < 0.0001 and p < 0.015, respectively). Although there were no treatment or treatment/gender effects on substrate oxidation, treatment increased 24-hour EE by 106 +/- 31 kcal/24 hours (p = 0.002), equivalent to 4.7 +/- 1.6 kcal/h (day; p = 0.005) and 3.3 +/- 1.5 kcal/h (night; p = 0.04). No significant differences were observed in hemodynamic parameters.
The present study provides evidence that consumption of a beverage containing green tea catechins, caffeine, and calcium increases 24-hour EE by 4.6%, but the contribution of the individual ingredients cannot be distinguished. Although this increase is modest, the results are discussed in relation to proposed public health goals, indicating that such modifications are sufficient to prevent weight gain. When consumed regularly as part of a healthy diet and exercise regime, such a beverage may provide benefits for weight control.
A pocket-sized metabolic analyzer for assessment of resting energy expenditure
Zhao D, Xian X, Terrera M, KrishnanR, Miller D, et al. (2014) A
pocket-sized metabolic analyzer for assessment of resting energy
expenditure. Clinical Nutr 33: 341-347.