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1.
Obes Rev ; 25(5): e13702, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38327045

RESUMEN

A systematic search was conducted in Medline Ovid, Embase, Scopus, and Cochrane Central Register of Controlled Trials up until March 2021 following PRISMA guidelines. Studies included evaluated ghrelin, GLP-1, PYY or appetite sensation via visual analogue scales (VASs) before and after Roux-en-Y gastric bypass (RYGB) in adults. A multilevel model with random effects for study and follow-up time points nested in study was fit to the data. The model included kcal consumption as a covariate and time points as moderators. Among the 2559 articles identified, k = 47 were included, among which k = 19 evaluated ghrelin, k = 40 GLP-1, k = 22 PYY, and k = 8 appetite sensation. Our results indicate that fasting ghrelin levels are decreased 2 weeks post-RYGB (p = 0.005) but do not differ from baseline from 6 weeks to 1-year post-RYGB. Postprandial ghrelin and fasting GLP-1 levels were not different from pre-surgical values. Postprandial levels of GLP-1 increased significantly from 1 week (p < 0.001) to 2 years post-RYGB (p < 0.01) compared with pre-RYGB. Fasting PYY increased at 6 months (p = 0.034) and 1 year (p = 0.029) post-surgery; also, postprandial levels increased up to 1 year (p < 0.01). Insufficient data on appetite sensation were available to be meta-analyzed.


Asunto(s)
Derivación Gástrica , Obesidad Mórbida , Adulto , Humanos , Ghrelina , Obesidad Mórbida/cirugía , Péptido YY , Péptido 1 Similar al Glucagón
2.
Obes Rev ; 24(9): e13598, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37395146

RESUMEN

A dysbiotic intestinal microbiome has been linked to chronic diseases such as obesity, which may suggest that interventions that target the microbiome may be useful in treating obesity and its complications. Appetite dysregulation and chronic systemic low-grade inflammation, such as that observed in obesity, are possibly linked with the intestinal microbiome and are potential therapeutic targets for the treatment of obesity via the microbiome. Dietary pulses (e.g., common beans) are composed of nutrients and compounds that possess the potential to modulate the gut microbiota composition and function which can in turn improve appetite regulation and chronic inflammation in obesity. This narrative review summarizes the current state of knowledge regarding the connection between the gut microbiome and obesity, appetite regulation, and systemic and adipose tissue inflammation. More specifically, it highlights the efficacy of interventions employing dietary common beans as a means to improve gut microbiota composition and/or function, appetite regulation, and inflammation in both rodent obesity and in humans. Collectively, results presented and discussed herein provide insight on the gaps in knowledge necessary for a comprehensive understanding of the potential of beans as a treatment for obesity while highlighting what further research is required to gain this understanding.


Asunto(s)
Microbioma Gastrointestinal , Humanos , Regulación del Apetito , Apetito , Obesidad/etiología , Inflamación/complicaciones
3.
EBioMedicine ; 83: 104192, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35965199

RESUMEN

BACKGROUND: Current paradigms for predicting weight loss in response to energy restriction have general validity but a subset of individuals fail to respond adequately despite documented diet adherence. Patients in the bottom 20% for rate of weight loss following a hypocaloric diet (diet-resistant) have been found to have less type I muscle fibres and lower skeletal muscle mitochondrial function, leading to the hypothesis that physical exercise may be an effective treatment when diet alone is inadequate. In this study, we aimed to assess the efficacy of exercise training on mitochondrial function in women with obesity with a documented history of minimal diet-induced weight loss. METHODS: From over 5000 patient records, 228 files were reviewed to identify baseline characteristics of weight loss response from women with obesity who were previously classified in the top or bottom 20% quintiles based on rate of weight loss in the first 6 weeks during which a 900 kcal/day meal replacement was consumed. A subset of 20 women with obesity were identified based on diet-resistance (n=10) and diet sensitivity (n=10) to undergo a 6-week supervised, progressive, combined aerobic and resistance exercise intervention. FINDINGS: Diet-sensitive women had lower baseline adiposity, higher fasting insulin and triglycerides, and a greater number of ATP-III criteria for metabolic syndrome. Conversely in diet-resistant women, the exercise intervention improved body composition, skeletal muscle mitochondrial content and metabolism, with minimal effects in diet-sensitive women. In-depth analyses of muscle metabolomes revealed distinct group- and intervention- differences, including lower serine-associated sphingolipid synthesis in diet-resistant women following exercise training. INTERPRETATION: Exercise preferentially enhances skeletal muscle metabolism and improves body composition in women with a history of minimal diet-induced weight loss. These clinical and metabolic mechanism insights move the field towards better personalised approaches for the treatment of distinct obesity phenotypes. FUNDING: Canadian Institutes of Health Research (CIHR-INMD and FDN-143278; CAN-163902; CIHR PJT-148634).


Asunto(s)
Insulinas , Obesidad , Adenosina Trifosfato/metabolismo , Canadá , Dieta Reductora , Ejercicio Físico/fisiología , Femenino , Humanos , Insulinas/metabolismo , Mitocondrias/metabolismo , Músculo Esquelético/metabolismo , Obesidad/metabolismo , Serina/metabolismo , Esfingolípidos/metabolismo , Triglicéridos/metabolismo , Pérdida de Peso
4.
Obes Surg ; 32(7): 1-12, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35441332

RESUMEN

PURPOSE: Roux-en-Y gastric bypass (RYGB) surgery produces significant weight loss. However, a number of patients experience weight regain years after surgery. Factors driving weight regain after surgical interventions are currently being explored. Our objective was to investigate appetite-related measures associated with weight regain after RYGB surgery. MATERIALS AND METHODS: Using a cross-sectional design, 29 participants (49.6 ± 9.1 years of age; current BMI 32.4 ± 4.7 kg/m2, 43.6 ± 8.9 months post-RYGB) were stratified into tertiles according to weight regain per month after nadir (weight maintenance (WM), n = 9; low weight regain (LWR), n = 10; and high weight regain (HWR), n = 10). The average weight regain was, by design, significantly different between the groups (WM = 2.2 ± 2.5 kg; LWR = 10.0 ± 3.4 kg; HWR = 14.9 ± 6.3 kg regained, p < 0.05). Appetite (visual analog scales), olfactory performance ("sniffin sticks"), eating behaviors (Three Factor Eating Questionnaire), food reward (Leeds Food Preference Questionnaire), and appetite-related hormones (ghrelin, PYY, GLP-1 and leptin) were measured fasting and in response to a standardized test meal. RESULTS: Dietary restraint was significantly higher than clinical cutoffs in WM and LWR (p < 0.05). As expected, significant time effects were noted for ghrelin, PYY, and GLP-1, but there were no group differences. CONCLUSION: The results suggest that appetite-related outcomes are similar across individuals who have maintained weight loss and experienced regain following RYGB.


Asunto(s)
Derivación Gástrica , Obesidad Mórbida , Apetito/fisiología , Mantenimiento del Peso Corporal , Estudios Transversales , Derivación Gástrica/métodos , Ghrelina , Péptido 1 Similar al Glucagón , Humanos , Obesidad Mórbida/cirugía , Aumento de Peso/fisiología , Pérdida de Peso/fisiología
5.
Int J Sport Nutr Exerc Metab ; 32(3): 214-225, 2022 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-35042186

RESUMEN

There has been much consideration over whether exogenous ketone bodies have the capacity to enhance exercise performance through mechanisms such as altered substrate metabolism, accelerated recovery, or neurocognitive improvements. This systematic review aimed to determine the effects of both ketone precursors and monoesters on endurance exercise performance. A systematic search was conducted in PubMed, SPORTDiscus, and CINAHL for randomized controlled trials investigating endurance performance outcomes in response to ingestion of a ketone supplement compared to a nutritive or nonnutritive control in humans. A meta-analysis was performed to determine the standardized mean difference between interventions using a random-effects model. Hedge's g and 95% confidence intervals (CI) were reported. The search yielded 569 articles, of which eight were included in this review (80 participants; 77 men and three women). When comparing endurance performance among all studies, no significant differences were found between ketone and control trials (Hedges g = 0.136; 95% CI [-0.195, 0.467]; p = .419). Subanalyses based on type of endurance tests showed no significant differences in time to exhaustion (Hedge's g = -0.002; 95% CI [-0.312, 0.308]; p = .989) or time trial (Hedge's g = 0.057; 95% CI [-0.282, 0.395]; p = .744) values. Based on these findings, exogenous ketone precursors and monoesters do not exert significant improvements on endurance exercise performance. While all studies reported an increase in blood ketone concentrations after ingestion, ketone monoesters appear to be more effective at raising concentrations than precursors.


Asunto(s)
Cetonas , Resistencia Física , Ingestión de Alimentos , Ejercicio Físico , Terapia por Ejercicio , Femenino , Humanos , Masculino , Resistencia Física/fisiología
6.
Appl Physiol Nutr Metab ; 47(2): 134-140, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34570984

RESUMEN

Reinforcing Relative Value (RRV) of food and impulsivity are associated with energy intake and obesity. This study investigated the degree to which changes in RRV and impulsivity independently or interactively predict changes in body weight and composition in women with overweight or obesity engaged in either fast or slow weight loss programs. Body weight, body composition, impulsivity (Barratt Impulsiveness Scale), and RRV snack (computerized Behavioural Choice Task) were measured at baseline and post-intervention in 30 women with obesity undergoing either slow (n = 14, -500 kcal/day, 20 weeks) or fast (n = 16, -1000 kcal/day, 10 weeks) weight reduction. No group × time effects were noted on body composition, impulsivity, or RRV, so participants from both groups were pooled for analysis. Multiple regression analyses indicated that none of the impulsivity variables predicted weight or fat mass (FM) loss. However, ΔRRV snack predicted ΔFM (r = 0.40, p = 0.046), whereby greater increases in RRV snack were associated with less FM loss. The results indicate that different rates of weight loss do not differentially affect RRV snack or impulsivity traits. However, changes in RRV snack predicted FM loss, suggesting that dietary interventions that either mitigate increases or foster reductions in the RRV snack may yield greater reductions in adiposity. Trial Registration clinicaltrials.gov identifier: NCT04866875. Novelty: No differences in RRV of food were noted between fast and slow weight loss. Weight loss from combined fast and slow groups led to a moderate-sized reduction in total impulsivity. Greater diet-induced increases in RRV snacks were associated with less body fat loss.


Asunto(s)
Obesidad/psicología , Sobrepeso/psicología , Refuerzo en Psicología , Bocadillos/psicología , Pérdida de Peso , Adiposidad , Adulto , Composición Corporal , Conducta de Elección , Ingestión de Energía , Femenino , Humanos , Conducta Impulsiva , Obesidad/terapia , Sobrepeso/terapia , Análisis de Regresión , Resultado del Tratamiento , Programas de Reducción de Peso
7.
Can J Physiol Pharmacol ; 100(5): 432-440, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-34910595

RESUMEN

Olfaction contributes to feeding behaviour and is modulated by changes in dopamine levels. Methylphenidate (MPH) increases brain dopamine levels and has been shown to reduce appetite and promote weight loss in patients with attention deficit hyperactivity disorder. The objectives of this study were to test the effect of MPH on olfaction, appetite, energy intake, and body weight (BW) on individuals with obesity. In a randomized, double-blind study, 12 participants (age 28.9 ± 6.7 years) with a body mass index (BMI) of 36.1 ± 4.5 kg/m2 were assigned to MPH (0.5 mg/kg) (n = 5) or placebo (n = 7) twice daily for 2 months. Appetite (visual analog scale), odour threshold (Sniffin' Sticks®), energy intake (food menu), and BW (DEXA scan) were measured at day 1 and day 60. MPH intake significantly increased odour threshold scores (6.3 ± 1.4 vs. 9.4 ± 2.1 and 7.9 ± 2.3 vs. 7.8 ± 1.9, respectively; p = 0.029) versus placebo. There was a significantly greater suppression of appetite sensations (desire to eat (p = 0.001), hunger (p = 0.008), prospective food consumption (p = 0.003)) and an increase in fullness (p = 0.028) over time in the MPH versus placebo. MPH suppressed appetite and improved olfactory sensitivity in individuals with obesity. These data provide novel findings on the favourable effects of MPH on appetite and weight regulation in individuals living with obesity.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad , Metilfenidato , Adulto , Apetito/fisiología , Dopamina/farmacología , Dopamina/uso terapéutico , Método Doble Ciego , Humanos , Metilfenidato/farmacología , Metilfenidato/uso terapéutico , Obesidad/complicaciones , Obesidad/tratamiento farmacológico , Olfato , Adulto Joven
8.
Appetite ; 169: 105844, 2022 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-34896388

RESUMEN

Sleep restriction (SR) often leads to an increase in energy intake (EI). However, large variability in EI after SR is often observed, which suggests that individual characteristics may affect food intake. The objective of this study was to explore the influence of characteristics generally associated with risk-taking (sensitivity to reward and personality traits: impulsiveness, sensation seeking) and implicit attitudes toward food on EI after sleep loss. 17 subjects completed the NEO-PI-3, an Implicit Association Test measuring implicit attitudes towards healthy and unhealthy foods, and the Sensitivity to Punishment and Sensitivity to Reward Questionnaire. 24h Ad libitum EI was assessed following a habitual sleep night, a 50% SR with an advanced wake time, and a 50% SR with a delayed bedtime. Changes in EI between each SR condition and the control condition (ΔEI) were calculated for each subject. Despite no changes in overall EI between sleep conditions, results showed large interindividual variations (-669 to +899 kcal) across SR conditions. Regression modeling showed that a lower sensation seeking and higher favorable implicit attitudes towards unhealthy food were significantly associated with increased ΔEI in the advanced wake time condition. For the delayed bedtime, lower sensation seeking was associated with increased ΔEI while controlling for age, sex, REM sleep, and implicit attitudes. These results suggest that certain personality traits and implicit attitudes toward food are associated with changes in EI after sleep loss.


Asunto(s)
Ingestión de Energía , Privación de Sueño , Actitud , Humanos , Personalidad , Sueño
9.
Gene ; 781: 145538, 2021 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-33631245

RESUMEN

BACKGROUND: The genetics of binge-eating disorder (BED) is an emerging topic, with dopaminergic genes being implicated in its etiology due to the role that dopamine (DA) plays in food reward sensitivity and self-regulation of eating behavior. However, no study to date has examined if DA genes influence response to behavioral treatment of BED. OBJECTIVE: The primary objective of this study was to examine the ability of DA-associated polymorphisms to predict BED treatment response measured using binge frequency over 12 months. As secondary objectives, this study examined cross-sectional relationships between these polymorphisms and anthropometrics in women living with and without BED and obesity. METHODS: Women aged 18-64 years old were genotyped for the DA-related SNPs DRD2/ANKK1 Taq1A (rs1800497) and COMT (rs4680), as well as the DA-related uVNTRs DAT-1 (SLC6A3) and MAO-A. A multi-locus DA composite score was formed from these 4 polymorphisms using genotypes known to have a functional impact resulting in modified DA signaling. Binge frequency (Eating Disorder Examination - Interview) and body composition (Tanita BC-418) were assessed in a pre-post analysis to examine genetic predictors of treatment response in women living with obesity and BED. Secondary data analysis was conducted on a cross-sectional comparison of three groups of women enrolled in trial group treatment for BED: women living with obesity and BED (n = 72), obesity without BED (n = 27), and normal-weight without BED (n = 45). RESULTS: There were no significant genotype × time interactions related to anthropometrics or binge frequency for any individual DA genotypes, or to the composite score reflecting DA availability. At baseline, there were no significant between-group differences in frequencies of DA-related alleles, nor were there associations between genotypes and anthropometrics. CONCLUSIONS: Our study found no evidence to suggest that the DRD2/ANKK1 Taq1A, COMT, MAO-A, or DAT-1 polymorphisms are associated with response to behavioral intervention for BED as measured by changes in binge frequency. Future studies should examine a greater variety of dopaminergic polymorphisms, other candidate genes that target other neurotransmitter systems, as well as examine their impact on both behavioral and pharmacological-based treatment for BED.


Asunto(s)
Trastorno por Atracón/genética , Dopamina/genética , Polimorfismo Genético , Adolescente , Adulto , Trastorno por Atracón/metabolismo , Catecol O-Metiltransferasa/genética , Estudios Transversales , Femenino , Genotipo , Humanos , Persona de Mediana Edad , Monoaminooxidasa/genética , Proteínas Serina-Treonina Quinasas/genética , Receptores de Dopamina D2/genética , Adulto Joven
10.
Appl Physiol Nutr Metab ; 46(3): 288-293, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33086027

RESUMEN

Recent advances in foundational research on energy balance and weight loss shed new light on earlier findings. Emerging evidence and insights around mental illness and client-centred, weight-inclusive approaches have implications for practitioners. This paper provides an overview of opinions from invited experts who presented at the Canadian Nutrition Society Thematic Conference in January 2019. Novelty: Weight loss involves an interplay of multiple factors, not diet alone. There is no "best diet" or treatment approach for weight loss. Future research should involve minimizing weight loss countermeasures and new health system-based approaches aimed at improving health.


Asunto(s)
Pérdida de Peso , Congresos como Asunto , Dieta , Metabolismo Energético , Humanos , Salud Mental , Obesidad/prevención & control , Sobrepeso/prevención & control
11.
Physiol Behav ; 228: 113201, 2021 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-33039382

RESUMEN

BACKGROUND: The aim of the study was to investigate whether early changes (1-week) in energy balance-related measures would predict changes in body weight (BW) and fat losses in women living with overweight/obesity. METHODS: BW, body composition (DXA), resting energy expenditure (REE)(indirect calorimetry), olfactory performance (Sniffin' Sticks), appetite and palatability (visual analogue scale) were measured at baseline, after a 1-week of caloric restriction as well as post-intervention (at 10 and 20 weeks) in a group of 30 women living with overweight/obesity. RESULTS: A significant decrease in REE (p = 0.033) was noted after 1 week. Fasting desire to eat (p = 0.004), hunger (p = 0.001) and prospective food consumption (p = 0.001) all increased after 1 week. Similarly, significant increases in AUC SQ for desire to eat (p = 0.01), hunger (p = 0.005) and prospective food consumption (p = 0.001) were noted after 1 week. However, these early changes were not associated to final BW or FM losses at the end of the weight loss intervention. CONCLUSION: Despite significant changes in REE and appetite soon after the onset of a BW loss intervention, these early changes do not seem to predict final BW or FM losses at the end of the program in women living with overweight/obesity.


Asunto(s)
Apetito , Sobrepeso , Composición Corporal , Peso Corporal , Ingestión de Energía , Metabolismo Energético , Femenino , Humanos , Menopausia , Obesidad , Estudios Prospectivos
12.
Physiol Behav ; 225: 113109, 2020 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-32730842

RESUMEN

Studies suggest that REM sleep is important for the maintenance of prefrontal cortex functioning. Therefore, reducing REM sleep may have an impact on cognitive functions such as impulse control and decision-making processes. This study examined the association between impulsiveness and sensation seeking personality traits, REM sleep and performance on a decision-making computer task following a habitual night of sleep and a partial sleep deprivation (PSD) condition with advanced wake-up time. Eighteen young adults participated in two experimental conditions: a control (habitual bedtime and wake time) and a 50% PSD with an advanced wake time. Impulsiveness and sensation seeking personality traits were measured with a personality inventory (NEO-PI-3), sleep was assessed using standard polysomnography and the Iowa Gambling Task (IGT) was completed at noon following each sleep condition. Results showed that when sleep deprived, participants choose more often to play riskier decks of cards during the last half of the IGT. Results also showed that REM sleep duration and REM sleep deprivation were associated with riskier decisions on the IGT. Moreover, impulsiveness was associated with riskier decisions after a normal night of sleep. These findings suggest that REM sleep duration and impulsiveness are important factors to consider while investigating decision-making processes under conditions of uncertainty and risk.


Asunto(s)
Juego de Azar , Sueño REM , Toma de Decisiones , Humanos , Sueño , Privación de Sueño , Adulto Joven
13.
RSC Adv ; 10(29): 17094-17100, 2020 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-35496928

RESUMEN

It is both challenging and desirable to have drug sensitizers released at acidic tumor pH for photodynamic therapy in cancer treatment. A pH-responsive carrier was prepared, in which fumed silica-attached 5,10,15,20-tetrakis(4-trimethylammoniophenyl)porphyrin (TTMAPP) was encapsulated into 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) nanocomposite liposomes. The sizes of agglomerates were determined by dynamic light scattering to be 115 nm for silica and 295 nm for silica-TTMAPP-DOPC liposomes. Morphological changes were also found in TEM images, showing liposome formation at pH 8.5 but collapse upon silanol protonation. TTMAPP release is enhanced from 13% at pH 7.5 to 80% at pH 2.3, as determined spectrophotometrically through dialysis membranes. Fluorescence emission of TTMAPP encapsulated in the dry film of liposomes was reduced to half at pH 8.6 when compared to that at pH 5.4, while the production of singlet oxygen was quintupled at pH 5.0 compared to pH 7.6. Upon treatment of human prostate cancer cells with liposomes containing 6.7 µM, 13 µM, 17 µM and 20 µM TTMAPP, the cell viabilities were determined to be 60%, 18%, 20% and 5% at pH 5.4; 58%, 30%, 25% and 10% at pH 6.3; and 90%, 82%, 68% and 35% at pH 7.4, respectively. Light-induced apoptosis in cancerous cells was only observed in the presence of liposomes at pH 6.3 and pH 5.4 but not at pH 7.4, as indicated by chromatin condensation.

14.
Public Health Nutr ; 23(4): 631-641, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31769383

RESUMEN

OBJECTIVE: To assess the associations among eating behaviour traits, food label use and diet quality and to evaluate if the association between eating behaviour traits and diet quality is mediated by food label use. DESIGN: Eating behaviour traits were assessed using the Three-Factor Eating Questionnaire (TFEQ), the Restraint Scale and the Intuitive Eating Scale, whereas food label use was measured with the Label Reading Survey. Diet quality (Canadian Healthy Eating Index) was assessed with an FFQ. SETTING: Cross-sectional study. PARTICIPANTS: Adults (n 385; mean (sd): BMI = 26·0 (4·9) kg/m2, age = 41·1 (15·0) years) involved in two previous experimental studies. RESULTS: When controlling for potential covariates, general food label use (ß = 1·18 (se 0·26), P < 0·0001) was the main determinant of diet quality, explaining 6·7 % of its variance. General food label use partly mediated the association between TFEQ-cognitive restraint and diet quality; the indirect effect (ßindirect (se); 95 % CI) was stronger in men (0·32 (0·10); 0·15, 0·55) than women (0·16 (0·05); 0·08, 0·27). General food label use also partly mediated the negative association between unconditional permission to eat and diet quality; the indirect effect (ßindirect (se); 95 % CI) was also stronger in men (-1·88 (0·55); -3·11, -0·96) than women (-1·03 (0·33); -1·81, -0·49). CONCLUSIONS: General food label use was the main determinant of diet quality and partly mediated the association between eating behaviour traits and diet quality. The stronger mediating effect observed in men suggests they rely more on food labelling when attempting to restrained themselves, which translates into better diet quality.


Asunto(s)
Dieta Saludable/psicología , Dieta Saludable/estadística & datos numéricos , Conducta Alimentaria/psicología , Etiquetado de Alimentos/estadística & datos numéricos , Adulto , Estudios Transversales , Encuestas sobre Dietas , Femenino , Humanos , Masculino , Análisis de Mediación , Persona de Mediana Edad , Encuestas y Cuestionarios
15.
Obes Rev ; 21(3): e12978, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31863637

RESUMEN

For humans to maintain a stable core temperature in cold environments, an increase in energy expenditure (EE) is required. However, little is known about how cold stimulus impacts energy balance as a whole, as energy intake (EI) has been largely overlooked. This review focuses on the current state of knowledge regarding how cold exposure (CE) impacts both EE and EI, while highlighting key gaps and shortcomings in the literature. Animal models clearly reveal that CE produces large increases in EE, while decreasing environmental temperatures results in a significant negative dose-response effect in EI (r=-.787, P<.001), meaning animals eat more as temperature decreases. In humans, multiple methods are used to administer cold stimuli, which result in consistent yet quantitatively small increases in EE. However, only two studies have measured ad libitum food intake in combination with acute CE in humans. Chronic CE (i.e., cold acclimation) studies have been shown to produce minimal changes in body weight, with an average compensation of ~126%. Although more studies are required to investigate how cold impacts EI in humans, results presented in this review warrant caution before presenting or considering CE as a potential adjunct to weight loss strategies.


Asunto(s)
Frío , Ingestión de Energía/fisiología , Metabolismo Energético/fisiología , Termogénesis/fisiología , Humanos
16.
Front Physiol ; 10: 1048, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31507431

RESUMEN

BACKGROUND/OBJECTIVES: Body composition (BC) does not always vary as a function of exercise induced energy expenditure (exercise EE - resting EE). Energy balance variables were measured to understand energy compensation (EC) in response to an exercise intervention performed at low (LOW) or moderate (MOD) intensity. SUBJECTS/METHODS: Twenty-one women with overweight/obesity (33 ± 5 kg/m2; 29 ± 10 yrs; 31 ± 4 ml O2/kg/min) were randomized to a 3-month LOW or MOD (40 or 60% of VÈ®2reserve, respectively) matched to expend 1500 kcal/week (compliance = 97 ± 5%). Body energy stores (DXA), energy intake (EI) (food menu and food diaries), resting EE (indirect calorimetry), total EE (doubly-labeled water), time spent in different activities (accelerometers), appetite (visual analog scale), eating behavior traits and food reward (liking and wanting) were assessed at baseline, after weeks 1 and 2 and at the end of the 3-month exercise intervention. RESULTS: EC based on BC changes (fat mass and fat-free mass) was 49 ± 79% and 161 ± 88% in LOW and MOD groups, respectively (p = 0.010). EI did not change significantly during the intervention. However, eating behavior traits and food reward had changed by the end of the 3-month supervised exercise. Non-structured physical activity (NSPA) decreased across the intervention (p < 0.002), independent of the intensity of the exercise training. CONCLUSION: Women with overweight/obesity training at LOW presented lower EC for a given energy cost of exercise. Our results strongly suggest that NSPA plays a major role in mediating the effects of exercise on energy balance and ultimately on changes in BC. CLINICAL TRIAL REGISTRATION: www.ClinicalTrials.gov, identifier ISRCTN31641049.

17.
Can J Cardiol ; 35(6): 712-720, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31151706

RESUMEN

BACKGROUND: It remains unclear whether cardiac rehabilitation (CR) provides similar benefits to patients with varying levels of body mass index (BMI). We assessed the psychosocial and cardiometabolic health of patients with increased BMI who completed CR. METHODS: The records of 582 patients who completed a 3-month outpatient CR program were analyzed. On the basis of their BMI at baseline, patients were categorized as normal (18.5-24.9 kg/m2), overweight (25.0-29.9 kg/m2), obese (30.0-34.9 kg/m2), or severely obese (≥ 35.0 kg/m2). Analysis of covariance was used to compare health-related quality of life (ie, Physical Component Summary [PCS] and Mental Component Summary scores), anxiety, depression, and cardiometabolic health indicators between BMI categories after CR. RESULTS: At baseline, patients with severe obesity, when compared with those with normal BMI, had lower PCS scores (39.7 ± 8.5 vs 44.4 ± 8.4, P < 0.001), elevated levels of anxiety (7.0 ± 3.7 vs 4.8 ± 3.2, P = 0.001) and depression (5.5 ± 4.4 vs 3.4 ± 3.7, P < 0.001), higher glycated hemoglobin A1C (6.5 ± 1.1 vs 5.6 ± 0.7%, P < 0.001) and triglycerides (1.6 ± 0.5 vs 1.1 ± 0.4 mmol/L, P < 0.001), and lower high-density lipoprotein cholesterol (1.1 ± 0.3 vs 1.2 ± 0.4 mmol/L, P = 0.006). After CR, notwithstanding a greater percent weight reduction in obesity (-3.5% ± 6.9% vs +1.1% ± 7.0%, P = 0.002) and severe obesity (-6.5% ± 6.9% vs +1.1% ± 7.0%, P < 0.001), smaller improvements in PCS scores were seen in the obese (4.1 ± 7.4 vs 6.9 ± 7.6, P = 0.011) and severely obese (4.1 ± 7.6 vs 6.9 ± 7.6, P = 0.039) when compared with those with normal BMI. CONCLUSIONS: Poorer psychosocial and cardiometabolic health at baseline coupled with smaller improvements in the PCS score suggest that patients with obesity and severe obesity will benefit from enhanced care in the CR setting.


Asunto(s)
Ansiedad/complicaciones , Índice de Masa Corporal , Rehabilitación Cardiaca/métodos , Enfermedades Cardiovasculares/prevención & control , Depresión/complicaciones , Obesidad/complicaciones , Sobrepeso/complicaciones , Anciano , Ansiedad/epidemiología , Ansiedad/rehabilitación , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/etiología , Depresión/epidemiología , Depresión/rehabilitación , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Obesidad/epidemiología , Obesidad/rehabilitación , Ontario/epidemiología , Sobrepeso/epidemiología , Sobrepeso/rehabilitación , Prevalencia , Calidad de Vida , Estudios Retrospectivos , Factores de Riesgo
18.
Nutrition ; 61: 208-212, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30822753

RESUMEN

OBJECTIVES: The genetics of binge-eating disorder (BED) is an emerging topic and one candidate pathway, namely the fat mass and obesity-associated (FTO) gene, may be implicated because of its role in food reward sensitivity and self-regulation of eating. The aims of this study were to examine the independent effects of variants of FTO on binge frequency in women with and without BED and to examine the moderating role of interpersonal attachment in this association. METHODS: Secondary data analysis was conducted on a cross-sectional comparison of three groups of women in a trial of group treatment for BED: BED with obesity (n = 73), BED without obesity (n = 55), and normal weight without BED (n = 50). Women were genotyped for five of the most common FTO single-nucleotide polymorphisms, rs9939609, rs8050136, rs3751812, rs1421085, and rs1121980, which have been related to body mass index and energy intake. Binge frequency (Eating Disorder Examination), body composition (bioelectric impedance), and attachment (Attachment Style Questionnaire) were assessed. RESULTS: There were no significant between-group differences for frequencies of FTO alleles, nor were there any significant anthropometric associations. The FTO × attachment interaction was significant whereby, relative to a low-risk FTO genotype, individuals with a high-risk genotype for the SNP rs1421085 and high-avoidant attachment had higher mean binge frequency than those with high genetic risk but low-avoidant attachment (ß = -7.96; t = -2.07; P = 0.042). CONCLUSIONS: FTO genotypes associated with risk for obesity and loss of control of eating, specifically rs1421085, may interact with insecure attachment in a way that may exacerbate binge eating among women with BED.


Asunto(s)
Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato/genética , Trastorno por Atracón/genética , Trastorno por Atracón/psicología , Obesidad/genética , Apego a Objetos , Adulto , Alelos , Antropometría , Composición Corporal , Índice de Masa Corporal , Bulimia/genética , Bulimia/psicología , Ensayos Clínicos como Asunto , Estudios Transversales , Impedancia Eléctrica , Femenino , Genotipo , Humanos , Peso Corporal Ideal , Persona de Mediana Edad , Obesidad/psicología , Polimorfismo de Nucleótido Simple
19.
Physiol Behav ; 199: 314-321, 2019 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-30496740

RESUMEN

BACKGROUND: Evidence of metabolic adaptations following weight loss is available in the literature. However, the impact of different degrees of caloric restriction on a comprehensive panel including energy expenditure (EE) and intake (EI), appetite, palatability and olfactory performance remains to be investigated. Accordingly, the purpose of the study was to investigate the changes in resting energy expenditure (REE), appetite, olfaction, palatability and EI in women who were engaged in either a slow (-500 kcal/day, 20-week) or in a rapid (-1000 kcal/ day, 10 weeks) weight loss program. METHODS: Thirty-six women with obesity were randomized to a slow or to a rapid weight loss group. Body composition (DXA), REE (indirect calorimetry), olfactory performance (Sniffin' Sticks), appetite (Visual Analogue Scale) were assessed at multiple time points during the intervention. RESULTS: A total of 30 participants completed the study (slow group n = 14; rapid group n = 16). Body weight decreased by -4.46 (3.99) % (P < .001) and - 6.23 (3.06) % (P = .001) in the slow and rapid groups, respectively. No differences in % weight loss were noted between groups (P = .175). Significant decreases in fat mass (P < .001), REE (P = .035), total EI (P = .001) were observed over time from both groups. However, no significant differences emerged between groups for any of the outcomes. The satiety quotient (SQ) at time 180 min significantly increased for desire to eat (P = .01), hunger (P = .011) and PFC (P = .002), while the area under the curve for postprandial appetite rates were not changed. No differences in palatability and olfactory performance were noted after the intervention. CONCLUSIONS: Our results suggest that different rates of weight loss exert similar effects on REE, appetite, satiety, and EI when weight loss are comparable.


Asunto(s)
Apetito/fisiología , Metabolismo Energético/fisiología , Obesidad/fisiopatología , Sobrepeso/fisiopatología , Pérdida de Peso/fisiología , Adulto , Composición Corporal/fisiología , Peso Corporal/fisiología , Calorimetría , Femenino , Humanos , Adulto Joven
20.
Br J Nutr ; 120(5): 583-592, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30058508

RESUMEN

Although there is a growing interest for the effects of intermittent fasting on energy balance, this study aimed to compare appetite, energy intake and food reward responses with an energy depletion induced either by 24-h food restriction or an equivalent deficit with exercise in healthy males. In all, twelve healthy lean males (21·5 (sd 0·5) years old; BMI: 22·5 (sd 1·7) kg/m2) participated in this study. Body composition, aerobic capacity, food preferences and energy intake were assessed. They randomly completed three conditions: (i) no depletion (CON); (ii) full 24-h energy restrictions (Def-EI); and (iii) exercise condition (Def-EX). Ad libitum energy intake and food reward were assessed at the end of each session. Appetite feelings were assessed regularly. Ad libitum energy intake was higher on Def-EI (7330 (sd 2975) kJ (1752 (sd 711) kcal) compared with that on CON (5301 (sd 1205) kJ (1267 (sd 288) kcal)) (P<0·05), with no difference between CON and Def-EX (6238 (sd 1741) kJ (1491 (sd 416) kcal) (P=0·38) and between Def-EX and Def-EI (P=0·22). There was no difference in the percent energy ingested from macronutrients. Hunger was lower on CON and Def-EX compared with Def-EI (P<0·001). Satiety was higher on CON and Def-EI compared with that on Def-EX (P<0·001). There was a significant interaction condition × time for food choice fat bias (P=0·04), showing a greater preference for high-fat v. low-fat food during Def-EI and Def-EX. Although 24-h fasting leads to increased energy intake at the following test meal (without total daily energy intake difference), increased hunger profile and decreased post-meal food choice fat bias, such nutritional responses are not observed after a similar deficit induced by exercise.


Asunto(s)
Apetito/fisiología , Metabolismo Energético/fisiología , Ejercicio Físico/fisiología , Ayuno/fisiología , Composición Corporal , Ingestión de Energía , Conducta Alimentaria , Preferencias Alimentarias/psicología , Humanos , Hambre/fisiología , Masculino , Consumo de Oxígeno , Recompensa , Saciedad/fisiología , Encuestas y Cuestionarios , Adulto Joven
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