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1.
Eur J Nutr ; 59(4): 1517-1527, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31139889

RESUMEN

PURPOSE: Diets with increased protein content are popular strategies for body weight regulation, but the effect of such diets for the colonic luminal environment is unclear. We aimed to investigate the associations between putative colorectal cancer-related markers and total protein intake, plant and animal proteins, and protein from red and processed meat in pre-diabetic adults (> 25 years). METHODS: Analyses were based on clinical and dietary assessments at baseline and after 1 year of intervention. Protein intake was assessed from 4-day dietary records. Putative colorectal cancer-related markers identified from 24-h faecal samples collected over three consecutive days were: concentration of short-chain fatty acids, phenols, ammonia, and pH. RESULTS: In total, 79 participants were included in the analyses. We found a positive association between change in total protein intake (slope: 74.72 ± 28.84 µmol per g faeces/E%, p = 0.01), including animal protein intake (slope: 87.63 ± 32.04 µmol per g faeces/E%, p = 0.009), and change in faecal ammonia concentration. For change in ammonia, there was a dose-response trend from the most negative (lowest tertile) to the most positive (highest tertile) association (p = 0.01): in the high tertile, a change in intake of red meat was positively associated with an increase in ammonia excretion (slope: 2.0 ± 0.5 µmol per g faeces/g/day, p < 0.001), whereas no such association was found in the low and medium tertile groups. CONCLUSION: Increases in total and animal protein intakes were associated with higher excretion of ammonia in faeces after 1 year in overweight pre-diabetic adults undertaking a weight-loss intervention. An increase in total or relative protein intake, or in the ratio of animal to plant protein, was not associated with an increase in faeces of any of the other putative colorectal cancer risk markers. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01777893.


Asunto(s)
Proteínas Dietéticas Animales/administración & dosificación , Neoplasias Colorrectales/complicaciones , Neoplasias Colorrectales/metabolismo , Sobrepeso/complicaciones , Proteínas de Plantas/administración & dosificación , Estado Prediabético/metabolismo , Programas de Reducción de Peso/métodos , Biomarcadores de Tumor/metabolismo , Estudios de Cohortes , Dieta/métodos , Heces , Femenino , Humanos , Internacionalidad , Masculino , Persona de Mediana Edad , Sobrepeso/metabolismo , Sobrepeso/terapia , Factores de Riesgo
3.
Int J Obes (Lond) ; 42(3): 580-583, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-28883543

RESUMEN

On the basis of the abundance of specific bacterial genera, the human gut microbiota can be divided into two relatively stable groups that might have a role in personalized nutrition. We studied these simplified enterotypes as prognostic markers for successful body fat loss on two different diets. A total of 62 participants with increased waist circumference were randomly assigned to receive an ad libitum New Nordic Diet (NND) high in fiber/whole grain or an Average Danish Diet for 26 weeks. Participants were grouped into two discrete enterotypes by their relative abundance of Prevotella spp. divided by Bacteroides spp. (P/B ratio) obtained by quantitative PCR analysis. Modifications of dietary effects of pre-treatment P/B group were examined by linear mixed models. Among individuals with high P/B the NND resulted in a 3.15 kg (95% confidence interval (CI): 1.55; 4.76, P<0.001) larger body fat loss compared with ADD, whereas no differences was observed among individuals with low P/B (0.88 kg (95% CI: -0.61; 2.37, P=0.25)). Consequently, a 2.27 kg (95% CI: 0.09; 4.45, P=0.041) difference in responsiveness to the diets were found between the two groups. In summary, subjects with high P/B ratio appeared more susceptible to lose body fat on diets high in fiber and whole grain than subjects with a low P/B ratio.


Asunto(s)
Bacteroides/fisiología , Microbioma Gastrointestinal/fisiología , Sobrepeso/dietoterapia , Prevotella/fisiología , Pérdida de Peso/fisiología , Adulto , Distribución de Chi-Cuadrado , Heces/microbiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sobrepeso/epidemiología , Resultado del Tratamiento , Circunferencia de la Cintura
4.
J Hum Hypertens ; 29(1): 58-63, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24759040

RESUMEN

Randomized trials have shown significant blood pressure (BP) reductions after increased protein compared with carbohydrate intake, but the effect on BP maintenance after initial weight loss is unclear. We examined the effect of a high-protein diet on the maintenance of reduced BP after weight loss in 420 overweight adults from the Diet, Obesity and Genes study. After an 8-week weight-loss period (>8% BW), subjects (42±6 years) were randomized to either a high-protein diet (23-28 en% protein) or a lower-protein control diet (10-15 en% protein) for 26 weeks. BMI after weight loss was 30.3±4.3 kg m(-2), BP was 118/73 mm Hg and 28 subjects (6.5%) used antihypertensive agents. Systolic BP during 26 weeks of weight maintenance dietary intervention increased in both treatment groups, but it was 2.2 mm Hg less (95% CI: -4.6 to 0.2 mm Hg, P=0.08) in the high-protein group than in the lower-protein control group. In 191 (pre)hypertensive subjects (baseline systolic BP⩾120 mm Hg), a larger difference was observed (-4.2 mm Hg (-7.7, -0.7), P=0.02). The effect was attenuated after adjustment for initial BP (-3.4 mm Hg (-6.9, -0.03), P=0.048), and after additional adjustment for weight change (-2.7 mm Hg (-6.1, 0.4), P=0.11). Adjustment for 24-h urinary excretion of sodium and potassium did not change the results. Diastolic BP yielded similar results. These findings suggest that a BP reduction after weight loss is better maintained when the intake of protein is increased at the expense of carbohydrates. This effect is partly mediated by body weight.


Asunto(s)
Presión Sanguínea , Proteínas en la Dieta/administración & dosificación , Hipertensión/dietoterapia , Obesidad/dietoterapia , Pérdida de Peso , Adulto , Índice de Masa Corporal , Dieta Baja en Carbohidratos , Europa (Continente) , Femenino , Humanos , Hipertensión/diagnóstico , Hipertensión/fisiopatología , Masculino , Persona de Mediana Edad , Estado Nutricional , Obesidad/diagnóstico , Obesidad/fisiopatología , Factores de Tiempo , Resultado del Tratamiento
5.
Int J Obes (Lond) ; 38(12): 1511-7, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24675714

RESUMEN

BACKGROUND: A high dietary protein (P) content and low glycemic index (LGI) have been suggested to be beneficial for weight management, but long-term studies are scarce. OBJECTIVE: The DIOGENES randomized clinical trial investigated the effect of P and GI on weight loss maintenance in overweight or obese adults in eight centers across Europe. This study reports the 1-year results in two of the centers that extended the intervention to 1 year. METHOD: After an 8-week low-calorie diet (LCD), 256 adults (body mass index >27 kg m(-)(2)) were randomized to five ad libitum diets for 12 months: high P/LGI (HP/LGI), HP/high GI (HP/HGI), low P/LGI (LP/LGI), LP/HGI and a control diet. During the first 6 months, foods were provided for free through a shop system and during the whole 12-month period, subjects received guidance by a dietician. Primary outcome variable was the change in body weight over the 12-month intervention period. RESULTS: During the LCD period, subjects lost 11.2 (10.8, 12.0) kg (mean (95% confidence interval (CI))). Average weight regain over the 12-month intervention period was 3.9 (95% CI 3.0-4.8) kg. Subjects on the HP diets regained less weight than subjects on the LP diets. The difference in weight regain after 1 year was 2.0 (0.4, 3.6) kg (P=0.017) (completers analysis, N=139) or 2.8 (1.4, 4.1) kg (P<0.001) (intention-to-treat analysis, N=256). No consistent effect of GI on weight regain was found. There were no clinically relevant differences in changes in cardiometabolic risk factors among diet groups. CONCLUSION: A higher protein content of an ad libitum diet improves weight loss maintenance in overweight and obese adults over 12 months.


Asunto(s)
Dieta Reductora , Proteínas en la Dieta/administración & dosificación , Índice Glucémico , Obesidad/terapia , Aumento de Peso , Pérdida de Peso , Población Blanca , Adulto , Índice de Masa Corporal , Peso Corporal , Restricción Calórica , Dieta con Restricción de Proteínas , Carbohidratos de la Dieta/administración & dosificación , Ingestión de Energía , Europa (Continente)/epidemiología , Familia , Femenino , Prueba de Tolerancia a la Glucosa , Humanos , Masculino , Encuestas Nutricionales , Obesidad/prevención & control , Cooperación del Paciente , Factores de Tiempo , Circunferencia de la Cintura
6.
Eur J Clin Nutr ; 67(9): 990-5, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23778783

RESUMEN

BACKGROUND/OBJECTIVES: To investigate acceptability and tolerability of diets of different protein and glycemic index (GI) content aimed at weight maintenance following a phase of rapid weight loss, as part of a large pan-European dietary intervention trial. SUBJECTS/METHODS: The Diogenes study (www.diogenes-eu.org) consisted of an initial 8-week rapid weight-loss phase (800-1000 kcal/day), followed by a 6-month weight maintenance intervention with five different diets varying in protein and GI content. Measurement of a range of outcomes relating to experience of the Diogenes diets in terms of acceptability, experience and mood were recorded via end of day questionnaires throughout the study. RESULTS: Weight change during the initial weight loss phase weakly, but positively correlated with acceptability of the programme (r range=-0.08 to 0.2, P 0.05, n=685 on four of five dimensions). Success at weight maintenance positively correlated with acceptance of the programme (r range=-0.21 to -0.34, P<0.001, n=540 for all five dimensions). The diets with higher protein content were more acceptable than the low protein (LP) diets, however, no differences between the high vs low GI diets were found concerning acceptability and tolerability. CONCLUSIONS: Results suggest that moderately high protein diets, compared with LP diets, are more acceptable diets for weight control in overweight individuals.


Asunto(s)
Dieta con Restricción de Proteínas , Índice Glucémico , Obesidad/dietoterapia , Prioridad del Paciente , Adulto , Índice de Masa Corporal , Peso Corporal , Dieta Reductora , Carbohidratos de la Dieta/administración & dosificación , Proteínas en la Dieta/administración & dosificación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pérdida de Peso
7.
Physiol Res ; 61(6): 597-607, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23098653

RESUMEN

Fatty acid composition of adipose tissue changes with weight loss. Palmitoleic acid as a possible marker of endogenous lipogenesis or its functions as a lipokine are under debate. Objective was to assess the predictive role of adipose triglycerides fatty acids in weight maintenance in participants of the DIOGENES dietary intervention study. After an 8-week low calorie diet (LCD) subjects with > 8 % weight loss were randomized to 5 ad libitum weight maintenance diets for 6 months: low protein (P)/low glycemic index (GI) (LP/LGI), low P/high GI (LP/HGI), high P/low GI (HP/LGI), high P/high GI (HP/HGI), and a control diet. Fatty acid composition in adipose tissue triglycerides was determined by gas chromatography in 195 subjects before the LCD (baseline), after LCD and weight maintenance. Weight change after the maintenance phase was positively correlated with baseline adipose palmitoleic (16:1n-7), myristoleic (14:1n-5) and trans-palmitoleic acid (16:1n-7t). Negative correlation was found with baseline oleic acid (18:1n-9). Lower baseline monounsaturated fatty acids (14:1n-5, 16:1n-7 and trans 16:1n-7) in adipose tissue triglycerides predict better weight maintenance. Lower oleic acid predicts lower weight decrease. These findings suggest a specific role of monounsaturated fatty acids in weight management and as weight change predictors.


Asunto(s)
Tejido Adiposo/química , Ácidos Grasos/química , Triglicéridos/metabolismo , Pérdida de Peso/fisiología , Tejido Adiposo/metabolismo , Adulto , Peso Corporal , Ácidos Grasos/metabolismo , Ácidos Grasos Monoinsaturados/química , Ácidos Grasos Monoinsaturados/metabolismo , Femenino , Índice Glucémico , Humanos , Masculino , Persona de Mediana Edad , Ácido Oléico/química , Ácido Oléico/metabolismo , Triglicéridos/análisis
8.
Int J Obes (Lond) ; 36(12): 1545-51, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22270380

RESUMEN

BACKGROUND: Circulating angiotensin-converting enzyme (ACE) was identified as a predictor of weight loss maintenance in overweight/obese women of the Diogenes project. OBJECTIVE: To investigate whether ACE acted also as a predictor in men of the Diogenes study and to compare it with that in women. DESIGN: Subjects, who lost ≥ 8% of body weight induced by low-caloric diet in an 8-week weight loss period, were assigned to weight loss maintenance with dietary intervention for 6 months. SUBJECTS: 125 overweight/obese healthy men from eight European countries who completed whole intervention. MEASUREMENTS: Concentrations and activity of serum ACE at baseline and after the 8-week weight loss, in addition to anthropometric and physiological parameters. RESULTS: Serum ACE concentration decreased by 11.3 ± 10.6% during the weight loss period in men. A greater reduction is associated with less body weight regain during the maintenance period (r=0.227, P=0.012). ACE change was able to predict a weight regain ≤ 20% after 6 months, with an odds ratio of 1.59 (95% confidence interval (CI): 1.09-2.33, P=0.016) for every 10% reduction, which was independent of body mass index and weight loss. The prediction power was weaker in men than in women, but without a significant sex difference (P=0.137). In pooled subjects (N=218), the odds ratio was 1.96 (95% CI: 1.46-2.64, P<0.001). CONCLUSIONS: A greater reduction of ACE during weight loss is favorable for weight maintenance in both men and women. This can offer useful information for personalized advice to improve weight loss maintenance. It also confirms the role of ACE in the metabolic pathways of weight regulation.


Asunto(s)
Obesidad/sangre , Peptidil-Dipeptidasa A/sangre , Pérdida de Peso , Adulto , Biomarcadores/sangre , Estudios Transversales , Dieta Reductora , Ingestión de Energía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Distribución por Sexo , Aumento de Peso
9.
Clin Obes ; 1(2-3): 62-8, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25585570

RESUMEN

There is a need to develop tools to predict individual weight loss maintenance and attrition prognosis. We aimed to identify predictors of weight loss maintenance outcome and attrition in subjects from eight European countries in the DiOGenes project. A total of 932 overweight/obese subjects (body mass index: 27-42 kg m(-2) ) were enrolled in an 8-week low-calorie diet (LCD). The 776 subjects (83%) who achieved at least 8% reduction in their initial body weight were randomized into five dietary arms varying in protein content and glycemic index for a 6-month weight maintenance period. Baseline characteristics, weight loss at weeks 1, 3 and 8 of LCD were assessed as predictors of weight loss maintenance and attrition using multivariate regression and correlation models. The multivariate model showed that the 6-month weight loss maintenance was predicted by: 7.889 - 0.343 × weight loss at week 3 + 1.505 × weight loss at week 8 + 2.422 × gender (0 = male and 1 = female gender) (R(2) = 51%, P = 0.0001). A greater weight loss at week 8 was associated with a lower attrition during the subsequent 6-month dietary intervention period (OR = 0.92, 95% CI: 0.88-0.97, P = 0.001). Furthermore, the men showed an increased likelihood for attrition during the dietary intervention period (OR = 1.54, 95% CI: 1.07-2.20, P = 0.02). A greater weight loss during 8 weeks of LCD and female gender predict better 6-month weight maintenance of weight loss, whereas the baseline characteristics did not predict outcome. Attrition could be strongly predicted by gender and weight loss during LCD.

10.
Nutr Diabetes ; 1: e4, 2011 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-23154296

RESUMEN

BACKGROUND: Intake of industrially produced trans fatty acids (TFAs) is, according to observational studies, associated with an increased risk of cardiovascular disease, but the causal mechanisms have not been fully elucidated. Besides inducing dyslipidemia, TFA intake is suspected to promote abdominal and liver fat deposition. OBJECTIVE: We examined the effect of a high intake of TFA as part of an isocaloric diet on whole-body, abdominal and hepatic fat deposition, and blood lipids in postmenopausal women. METHODS: In a 16-week double-blind parallel intervention study, 52 healthy overweight postmenopausal women were randomized to receive either partially hydrogenated soybean oil providing 15.7 g day(-1) of TFA or a control oil with mainly oleic and palmitic acid. Before and after the intervention, body composition was assessed by dual-energy X-ray absorptiometry, abdominal fat by magnetic resonance (MR) imaging, and liver fat by (1)H MR spectroscopy. RESULTS: Compared with the control fat, TFA intake decreased plasma high-density lipoprotein (HDL)-cholesterol by 10%, increased low-density lipoprotein (LDL)-cholesterol by 18% and resulted in an increased LDL/HDL-cholesterol ratio (baseline adjusted mean (95% CI) difference between diet groups 0.41 (0.22; 0.60); P<0.001). TFA tended to increase the body fat (0.46 (-0.20; 1.17) kg; P=0.16) and waist circumference (1.1 (-0.1; 2.4) cm; P=0.08) more than the control fat, whereas neither abdominal nor liver fat deposition was affected by TFA. CONCLUSION: The adverse effect of dietary TFA on cardiovascular disease risk involves induction of dyslipidemia, and perhaps body fat, whereas weight gain-independent accumulation of ectopic fat could not be identified as a contributory factor during short-term intake.

11.
Eur J Clin Nutr ; 64(9): 994-9, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20588292

RESUMEN

OBJECTIVE: The purpose of this study was to investigate whether pre-treatment subject characteristics and weight change during the first weeks of a low-calorie diet (LCD) can predict weight loss outcomes at the end of a controlled 8-week weight loss period in overweight and obese adults. SUBJECTS: A total of 932 overweight and obese subjects of both genders were included at eight European centers, and underwent an 8-week LCD period. RESULTS: The weight loss at week 8 was positively correlated with initial body weight (Spearman's rho=0.62), height (rho=0.43), body mass index (rho=0.43), waist (rho=0.48) and hip circumference (rho=0.33), sagittal diameter (rho=0.45), fat mass (rho=0.35) and fat-free mass (rho=0.52), and gender (rho=-0.36) (all P<0.01). In the multivariate regression model, adjusted for center, only initial body weight, early weight loss (week 1) and weight loss at week 3 were significant predictors of weight loss outcome at week 8: weight loss (kg) at week 8=0.09+0.046 x baseline body weight (kg)-0.311 x weight loss (kg) at week 1+1.284 x weight loss (kg) at week 3 (R(2)=68%, P<0.0001). A weight loss of > or =2.6 kg at week 1 during the LCD period was identified as the optimal cut-off predictor for at least 10 kg weight loss at week 8. CONCLUSIONS: This study suggests that initial body weight, early weight loss (week 1) and weight loss at week 3 are predictors of final weight loss during an 8-week LCD, and may be used as early biomarkers of subsequent responses to an LCD diet.


Asunto(s)
Dieta Reductora , Obesidad/dietoterapia , Sobrepeso/dietoterapia , Pérdida de Peso/fisiología , Adulto , Peso Corporal/fisiología , Restricción Calórica , Femenino , Humanos , Masculino , Valor Predictivo de las Pruebas , Valores de Referencia , Factores Sexuales , Factores de Tiempo , Resultado del Tratamiento
12.
Ann N Y Acad Sci ; 1190: 25-41, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20388134

RESUMEN

Many dietary factors or substances exert effects on the three components of energy balance, and one strategy for tackling weight gain could be to use the inherent properties of these substances. Here, we will review the evidence regarding nutritional factors with a potential impact on energy balance, such as wholegrain foods, dietary fiber and protein content, calcium, and certain spices. There is ample evidence to suggest that dietary protein, wholegrain, and fiber promote satiety and either reduce energy absorption or stimulate energy expenditure. Dietary calcium reduces fat absorption, and a sufficient intake may also prevent excessive hunger during weight loss diets. Chili and mustard have beneficial effects on energy balance, although the quantitative importance of this may be modest. Manipulation of diet composition with an aim to prevent weight gain and weight regain is a promising avenue of research.


Asunto(s)
Alimentos , Obesidad/metabolismo , Animales , Calcio/metabolismo , Calcio/fisiología , Fibras de la Dieta/metabolismo , Humanos
13.
Obes Rev ; 11(1): 76-91, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19470086

RESUMEN

Diogenes is a Pan-European, randomized, controlled dietary intervention study investigating the effects of dietary protein and glycaemic index on weight (re)gain, metabolic and cardiovascular risk factors in obese and overweight families in eight European centres. The article is methodological in character, and the presentation of 'results' will be limited to baseline characteristics of the study populations included. A total of 891 families with at least one overweight/obese parent underwent screening. The parents started an initial 8-week low-calorie diet and families with minimum one parent attaining a weight loss of > or = 8%, were randomized to one of five energy ad libitum, low-fat (25-30 E%) diets for 6 or 12 months: low protein/low glycaemic index, low protein/high glycaemic index, high protein/low glycaemic index, high protein/high glycaemic index or control (national dietary guidelines). At two centres the families were provided dietary instruction plus free foods for 6 months followed by 6-month dietary instruction only. At the remaining six centres the families received dietary instruction only for 6 months. The median weight loss during the low-calorie diet was 10.3 kg (inter-quartile range: 8.7-12.8 kg, n = 775). A total of 773 adults and 784 children were randomized to the 6-month weight (re)gain prevention phase. Despite major cultural and dietary regional differences in Europe, interventions addressing effects of dietary factors are feasible with a reasonable attrition.


Asunto(s)
Dieta Reductora , Carbohidratos de la Dieta/clasificación , Índice Glucémico , Obesidad/dietoterapia , Pérdida de Peso , Adolescente , Adulto , Anciano , Niño , Preescolar , Carbohidratos de la Dieta/administración & dosificación , Carbohidratos de la Dieta/metabolismo , Grasas de la Dieta/administración & dosificación , Proteínas en la Dieta/administración & dosificación , Proteínas en la Dieta/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Adulto Joven
14.
Obes Rev ; 11(1): 67-75, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19573053

RESUMEN

The aim of this study was to describe the development and implementation of a multifaceted, low-fat, weight-loss strategy for a Pan-European randomized controlled dietary intervention study, Diogenes. There were 891 families with at least one overweight/obese parent who underwent screening. Eligible, overweight/obese adults followed an 8-week weight-loss phase with a fixed low-energy diet (800 kcal). On attaining weight loss of > or = 8%, families were randomized to a 6- or 12-month low-fat (25-30%E) diet either based on national dietary guidelines or one of four interventions: low protein (LP)/low glycaemic index (LGI), LP/high GI (HGI), high protein (HP)/LGI and HP/HGI. The impact of each diet in preventing weight (re)gain was tested. A points-based system was used to manipulate dietary protein and carbohydrate. Manipulating carbohydrate composition involved substituting foods with a relatively high or low GI. A questionnaire was designed and completed by study investigators, providing feedback on the dietary intervention methods used to inform future interventions. The points system allowed macronutrient manipulations without compromising dietary flexibility or enforcing energy restrictions. Reported centre/participant differences in the ease of implementing the intervention may reflect dietary diversity and personal preferences for specific weight-management strategies. The points system provides a useful starting point for designing improved experimental paradigms for the manipulation of dietary intake in future trials.


Asunto(s)
Dieta Reductora , Índice Glucémico , Obesidad/dietoterapia , Pérdida de Peso , Adolescente , Adulto , Anciano , Niño , Preescolar , Comparación Transcultural , Dieta Baja en Carbohidratos , Dieta con Restricción de Grasas , Dieta con Restricción de Proteínas , Carbohidratos de la Dieta/administración & dosificación , Carbohidratos de la Dieta/clasificación , Carbohidratos de la Dieta/metabolismo , Grasas de la Dieta/administración & dosificación , Proteínas en la Dieta/administración & dosificación , Europa (Continente) , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
15.
Diabetes Obes Metab ; 11(6): 596-602, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19383030

RESUMEN

AIM: No studies have assessed if changes in visceral adipose tissue (VAT) during weight loss differ between women and men with comparable amounts of VAT at baseline. The aim of this study was to assess if changes in VAT induced by a low-calorie diet (LCD) differ between women and men. METHODS: In this post hoc analysis of an existing database, abdominal adipose tissue was evaluated before and after an 8-week LCD (800-1000 kcal/day) by a single-slice magnetic resonance scan performed at the abdominal level. Body composition was measured by dual X-ray energy absorptiometry. RESULTS: Data from 111 obese subjects (85 women and 26 men) were available. Relative changes in VAT were found to be more pronounced in men [mean (95% CI): -32.6% (-38.7 to -26.6)] than in women [-21.9% (-25.0 to -18.8)] (p = 0.003) after correction for relative changes in fat mass (FM). When analysing only the data from a subgroup of 23 women and 23 men who were matched for similar visceral to abdominal subcutaneous fat ratio at baseline, these differences could not be observed anymore: the change in VAT was -33.7% (-38.7 to -28.7) in men and -26.8% (-31.8 to -21.8) in women (p = 0.07). CONCLUSIONS: This study suggests that relative changes in VAT during a LCD may be greater in men than in women even after taking relative changes in FM into account. However, these differences disappear when properly matching the subjects for baseline amounts of VAT.


Asunto(s)
Composición Corporal/fisiología , Restricción Calórica , Grasa Intraabdominal/fisiología , Pérdida de Peso/fisiología , Absorciometría de Fotón , Adulto , Anciano , Femenino , Humanos , Grasa Intraabdominal/anatomía & histología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Factores Sexuales , Adulto Joven
16.
Obes Rev ; 10(1): 58-67, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18721231

RESUMEN

The discovery of cannabinoids, with the well-known stimulatory effect of Cannabis sativa on appetite, has offered a new drug target for obesity treatment. Cannabinoids act on two different receptors: CB1 receptors which are sited in the brain and many peripheral tissues, and CB2 receptors which are primarily found in immune system cells. Cannabinoid receptor antagonists act centrally by blocking CB1 receptors, thereby reducing food intake. Moreover, they probably also act peripherally by increasing thermogenesis and therefore energy expenditure, as has been suggested by animal experiments. Despite these promising mechanisms of action, recent clinical studies examining the effect of the two CB1 receptor antagonists rimonabant and taranabant showed that the attained weight loss did not exceed that attained with other currently approved anti-obesity medications. Moreover, potentially severe psychiatric adverse effects limit their clinical use. As several new CB1 receptor antagonists are presently undergoing development, it remains to be elucidated to what extent they differ in terms of efficacy and safety. This review primarily discusses how close cannabinoid receptor antagonists are to the ideal anti-obesity drug, with respect to their mechanisms of action, clinical effectiveness and safety.


Asunto(s)
Fármacos Antiobesidad/uso terapéutico , Antagonistas de Receptores de Cannabinoides , Metabolismo Energético/efectos de los fármacos , Obesidad/tratamiento farmacológico , Fármacos Antiobesidad/efectos adversos , Cannabinoides/farmacología , Ensayos Clínicos como Asunto , Ingestión de Energía/efectos de los fármacos , Humanos , Pérdida de Peso/efectos de los fármacos
17.
Phys Rev Lett ; 101(4): 042001, 2008 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-18764320

RESUMEN

The first measurements of xF-dependent single-spin asymmetries of identified charged hadrons, pi+/-, K+/-, and protons, from transversely polarized proton-proton collisions at 62.4 GeV at RHIC are presented. Large asymmetries are seen in the pion and kaon channels. The asymmetries in inclusive pi+ production, AN(pi+), increase with xF from 0 to approximately 0.25 and AN(pi-) decrease from 0 to approximately -0.4. Observed asymmetries for K- unexpectedly show positive values similar to those for K+, increasing with xF, whereas proton asymmetries are consistent with zero over the measured kinematic range. Comparisons of the data with predictions of QCD-based models are presented.

18.
Phys Rev Lett ; 98(25): 252001, 2007 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-17678015

RESUMEN

We present particle spectra for charged hadrons pi(+/-), K(+/-), p, and p[over] from pp collisions at square root[s] = 200 GeV measured for the first time at forward rapidities (2.95 and 3.3). The kinematics of these measurements are skewed in a way that probes the small momentum fraction in one of the protons and large fractions in the other. Large proton to pion ratios are observed at values of transverse momentum that extend up to 4 GeV/c, where protons have momenta up to 35 GeV. Next-to-leading order perturbative QCD calculations describe the production of pions and kaons well at these rapidities, but fail to account for the large proton yields and small p[over]/p ratios.

19.
Phys Rev Lett ; 94(16): 162301, 2005 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-15904216

RESUMEN

We have measured rapidity densities dN/dy of pi+/- and K+/- over a broad rapidity range (-0.1 < y < 3.5) for central Au + Au collisions at square root(sNN) = 200 GeV. These data have significant implications for the chemistry and dynamics of the dense system that is initially created in the collisions. The full phase-space yields are 1660 +/- 15 +/- 133 (pi+), 1683 +/- 16 +/- 135 (pi-), 286 +/- 5 +/- 23 (K+), and 242 +/- 4 +/- 19 (K-). The systematics of the strange to nonstrange meson ratios are found to track the variation of the baryochemical potential with rapidity and energy. Landau-Carruthers hydrodynamics is found to describe the bulk transport of the pions in the longitudinal direction.

20.
Phys Rev Lett ; 94(3): 032301, 2005 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-15698255

RESUMEN

Charged-particle pseudorapidity densities are presented for the d + Au reaction at sqrt[s(NN)] = 200 GeV with -4.2 < or = eta < or = 4.2. The results, from the BRAHMS experiment at BNL Relativistic Heavy-Ion Collider, are shown for minimum-bias events and 0%-30%, 30%-60%, and 60%-80% centrality classes. Models incorporating both soft physics and hard, perturbative QCD-based scattering physics agree well with the experimental results. The data do not support predictions based on strong-coupling, semiclassical QCD. In the deuteron-fragmentation region the central 200 GeV data show behavior similar to full-overlap d+Au results at sqrt[s(NN)] = 19.4 GeV.

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