RESUMEN
BACKGROUND & AIMS: Relatively high-protein diets are effective for body weight loss, and subsequent weight maintenance, yet it remains to be shown whether these diets would prevent a positive energy balance. Therefore, high-protein diet studies at a constant body weight are necessary. The objective was to determine fullness, energy expenditure, and macronutrient balances on a high-protein low-carbohydrate (HPLC) diet compared with a high-carbohydrate low-protein (HCLP) diet at a constant body weight, and to assess whether effects are transient or sustained after 12 weeks. METHODS: A randomized parallel study was performed in 14 men and 18 women [mean ± SD age: 24 ± 5 y; BMI (in kg/m(2)): 22.8 ± 2.0] on diets containing 30/35/35 (HPLC) or 5/60/35 (HCLP) % of energy from protein/carbohydrate/fat. RESULTS: Significant interactions between dietary intervention and time on total energy expenditure (TEE) (P = 0.013), sleeping metabolic rate (SMR) (P = 0.040), and diet-induced thermogenesis (DIT) (P = 0.027) appeared from baseline to wk 12. TEE was maintained in the HPLC diet group, while it significantly decreased throughout the intervention period in the HCLP diet group (wk 1: P = 0.002; wk 12: P = 0.001). Energy balance was maintained in the HPLC diet group, and became positive in the HCLP diet group at wk 12 (P = 0.008). Protein balance varied directly according to the amount of protein in the diet, and diverged significantly between the diets (P = 0.001). Fullness ratings were significantly higher in the HPLC vs. the HCLP diet group at wk 1 (P = 0.034), but not at wk 12. CONCLUSIONS: Maintenance of energy expenditure on HPLC vs. HCLP diets at a constant body weight may prevent development of a positive energy balance, despite transiently higher fullness. The study was registered on clinicaltrials.gov with Identifier: NCT01551238.
Asunto(s)
Peso Corporal , Carbohidratos de la Dieta/administración & dosificación , Proteínas en la Dieta/administración & dosificación , Metabolismo Energético , Adulto , Apetito , Biomarcadores/orina , Composición Corporal , Índice de Masa Corporal , Dieta Baja en Carbohidratos , Dieta con Restricción de Proteínas , Femenino , Humanos , Masculino , Nitrógeno/orina , Método Simple Ciego , Adulto JovenRESUMEN
Energy- and food-reward homeostasis is the essential component for maintaining energy balance and its disruption may lead to metabolic disorders, including obesity and diabetes. Circadian alignment, quality sleep and sleep architecture in relation to energy- and food-reward homeostasis are crucial. A reduced sleep duration, quality sleep and rapid-eye movement sleep affect substrate oxidation, leptin and ghrelin concentrations, sleeping metabolic rate, appetite, food reward, hypothalamic-pituitary-adrenal (HPA)-axis activity, and gut-peptide concentrations, enhancing a positive energy balance. Circadian misalignment affects sleep architecture and the glucose-insulin metabolism, substrate oxidation, homeostasis model assessment of insulin resistance (HOMA-IR) index, leptin concentrations and HPA-axis activity. Mood disorders such as depression occur; reduced dopaminergic neuronal signaling shows decreased food reward. A good sleep hygiene, together with circadian alignment of food intake, a regular meal frequency, and attention for protein intake or diets, contributes in curing sleep abnormalities and overweight/obesity features by preventing overeating; normalizing substrate oxidation, stress, insulin and glucose metabolism including HOMA-IR index, and leptin, GLP-1 concentrations, lipid metabolism, appetite, energy expenditure and substrate oxidation; and normalizing food reward. Synchrony between circadian and metabolic processes including meal patterns plays an important role in the regulation of energy balance and body-weight control. Additive effects of circadian alignment including meal patterns, sleep restoration, and protein diets in the treatment of overweight and obesity are suggested.
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Ingestión de Energía/fisiología , Metabolismo Energético/fisiología , Homeostasis/fisiología , Obesidad/prevención & control , Sueño/fisiología , Ritmo Circadiano , Humanos , Obesidad/fisiopatologíaRESUMEN
CONTEXT: Epidemiologically, an inverse relationship between body mass index (BMI) and sleep duration is observed. Intra-individual variance in the amount of slow wave sleep (SWS) or rapid eye movement (REM) sleep has been related to variance of metabolic and endocrine parameters, which are risk factors for the disturbance of energy balance (EB). OBJECTIVE: To investigate inter-individual relationships between EB (EB= energy intake-energy expenditureâ£, MJ/24 h), SWS or REM sleep, and relevant parameters in normal-weight men during two 48 h stays in the controlled environment of a respiration chamber. SUBJECTS AND METHODS: A total of 16 men (age 23±3.7 years, BMI 23.9±1.9 kg m(-2)) stayed in the respiration chamber twice for 48 h to assure EB. Electroencephalography was used to monitor sleep (2330-0730 hrs). Hunger and fullness were scored by visual analog scales; mood was determined by State Trait Anxiety Index-state and food reward by liking and wanting. Baseline blood and salivary samples were collected before breakfast. Subjects were fed in EB, except for the last dinner, when energy intake was ad libitum. RESULTS: The subjects slept on average 441.8±49 min per night, and showed high within-subject reliability for the amount of SWS and REM sleep. Linear regression analyses showed that EB was inversely related to the amount of SWS (r=-0.43, P<0.03), and positively related to the amount of REM sleep (r=0.40, P<0.05). Relevant parameters such as hunger, reward, stress and orexigenic hormone concentrations were related to overeating, as well as to the amount of SWS and REM sleep, however, after inclusion of these parameters in a multiple regression, the amount of SWS and REM sleep did not add to the explained variance of EB, which suggests that due to their individual associations, these EB parameters are mediator variables. CONCLUSION: A positive EB due to overeating, was explained by a smaller amount of SWS and higher amount of REM sleep, mediated by hunger, fullness, State Trait Anxiety Index-state scores, glucose/insulin ratio, and ghrelin and cortisol concentrations.
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Ansiedad/metabolismo , Ingestión de Energía , Metabolismo Energético , Hambre , Hidrocortisona/metabolismo , Hiperfagia/metabolismo , Fases del Sueño , Sueño REM , Adolescente , Adulto , Análisis de Varianza , Índice de Masa Corporal , Conducta de Elección , Electroencefalografía , Humanos , Masculino , Consumo de Oxígeno , Saciedad , Fases del Sueño/fisiología , Adulto JovenRESUMEN
OBJECTIVES: The objectives of this study were to determine the long-term survival and success rates of autotransplanted canines and to investigate the influence of various parameters on the long-term success rate. STUDY DESIGN: Fifty-nine patients (73 transplanted canines) volunteered to participate in this study. The mean follow-up time was 11 years. Different parameters that could influence the outcome of transplantation were examined in the patient files. Each transplanted canine was clinically and radiologically evaluated. Logistic regression analyses were performed. RESULTS: The survival rate was 75.3%, because 18 transplanted teeth were lost before examination. The success rate for all transplanted teeth was 57.5%, because 42 transplanted teeth were evaluated as clinically successful. The most significant parameter in determining the success rate of autotransplantation was age at transplantation (P = .0429). CONCLUSION: Autotransplantation of impacted canines may have a successful outcome 11 years after transplantation. The success rate increases when performing the transplantation at a younger age.