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Macronutrient composition and its effect on body composition changes during weight loss therapy in patients with non-alcoholic fatty liver disease: Secondary analysis of a randomized controlled trial.
Lindqvist, C, Holmer, M, Hagström, H, Petersson, S, Tillander, V, Brismar, TB, Stål, P
Nutrition (Burbank, Los Angeles County, Calif.). 2023;110:111982
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Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease worldwide and it is closely linked to overweight and obesity. Weight loss leads to an amelioration of NAFLD, which preferably should lead to loss of fat mass while maintaining lean body mass. The aim of this study was to examine if different diet compositions during weight loss therapy were associated with different reductions in abdominal fat mass compared with standard weight loss advice given by a physician. This study was a secondary analysis of data collected in an open-label, randomised controlled trial. The trial examined the effect of two popular weight loss diets, calorie-restricted intermittent fasting (5:2) and a calorie-restricted low-carbohydrate high-fat (LCHF) diet, compared with standard of care (SOC) on reduction in liver fat in 74 persons with NAFLD. Results show that a dietitian-led nutrition counselling treatment with an LCHF or 5:2 diet reduced weight to a higher extent than physician-supported SOC during a 12-wk treatment. Improvements in most of the variables related to body composition parameters and metabolic function were found, independent of dietary composition. Furthermore, during weight loss, visceral fat was mobilized to a greater extent than subcutaneous fat. Authors conclude that further studies are needed with a focus on the effect of diet composition on body composition changes during weight loss.
Abstract
OBJECTIVES Dietary composition may affect body composition during weight loss therapy. We tested the hypothesis of whether dietary macronutrient composition influences the reduction of total abdominal adipose tissue, subcutaneous adipose tissue (SAT), or visceral adipose tissue (VAT) during weight loss. METHODS Dietary macronutrient composition and body composition were analyzed as a secondary outcome of a randomized controlled trial of 62 participants with non-alcoholic fatty liver disease. Patients were randomly assigned to a calorie-restricted intermittent fasting (5:2), calorie-restricted low-carbohydrate high-fat (LCHF), or healthy lifestyle advice (standard-of-care) diet in a 12-wk intervention phase. Dietary intake was assessed by self-reported 3-d food diaries and by characterization of total plasma fatty acid profile. Percentage of energy intake (E%) from different macronutrients was calculated. Body composition was assessed by magnetic resonance imaging and anthropometric measurements. RESULTS The macronutrient composition differed significantly between the 5:2 (fat 36 E% and carbohydrates 43 E%) and the LCHF (fat 69 E% and carbohydrates 9 E%) groups (P < 0.001). Weight loss was similar in the 5:2 and LCHF groups (-7.2 [SD = 3.4] kg versus 8.0 [SD = 4.8] kg; P = 0.44) and significantly larger than for standard of care (-2.5 kg [SD = 2.3]; P < 0.001). The volume of total abdominal fat, adjusted for height, decreased on average by 4.7% (standard of care), 14.3% (5:2), and 17.7% (LCHF), with no significant differences between the 5:2 and LHCF groups (P = 0.32). VAT and SAT, adjusted for height, decreased on average by 17.1% and 12.7% for 5:2, respectively, and by 21.2% and 17.9% for LCHF, with no significant group differences (VAT [P = 0.16] and SAT [P = 0.10]). VAT was mobilized to a greater extent than SAT in all diets. CONCLUSIONS The 5:2 and LCHF diets had similar effects on changes in intraabdominal fat mass and anthropometrics during weight loss. This might indicate that overall weight loss is more important than diet composition to achieve changes in total abdominal adipose tissue, VAT, or SAT. The results of the present study suggest that there is a need for further studies on the effect of diet composition on body composition changes during weight loss therapy.
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Intramyocellular Lipids, Insulin Resistance, and Functional Performance in Patients with Severe Obstructive Sleep Apnea.
Chien, MY, Lee, PL, Yu, CW, Wei, SY, Shih, TT
Nature and science of sleep. 2020;12:69-78
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Obstructive sleep apnoea syndrome (OSA) is characterized by repeated occlusion of the upper airway during sleep, resulting in periods of intermittent hypoxemia [low level of oxygen in blood]. The aim of this study was to (a) investigate the intramyocellular lipids (IMCL) and extramyocellular lipids (EMCL), biochemical data, and functional performance in patients with severe OSA versus controls, and (b) examine the correlations between intra-muscular lipid contents and biochemical and performance variables. This study is a clinical trial that recruited 20 patients with OSA and body mass index(BMI)-matched controls. Results demonstrate that patients with OSA had significantly lower IMCL and EMCL values when compared with their age-, and BMI-matched controls without OSA. Furthermore, compared with controls, patients with OSA had significantly reduced functional performance and exhibited abnormal biochemical data, including glucose and insulin levels and lipid profiles. Authors conclude that additional large-scale clinical trials are required to further explore the complex mechanism between OSA, muscle metabolism, and insulin action.
Abstract
PURPOSE An increasing number of studies have linked the severity of obstructive sleep apnea (OSA) with metabolic dysfunction. However, little is known about the lipid compartments (intramyocellular [IMCL] and extramyocellular [EMCL] lipids) inside the musculature in these patients. The present study was designed to investigate the IMCL and EMCL, biochemical data, and functional performance in patients with severe OSA, and to examine the correlations between intramuscular lipid contents and test variables. PARTICIPANTS AND METHODS Twenty patients with severe OSA (apnea-hypopnea index [AHI]: ≥30/h; body mass index [BMI]: 26.05±2.92) and 20 age- and BMI-matched controls (AHI <5/h) were enrolled. Proton magnetic resonance spectroscopy was used to measure the IMCL and EMCL of the right vastus lateralis muscle. Biochemical data, including levels of fasting plasma glucose, insulin, lipid profiles, and high-sensitivity C-reactive protein (hsCRP), were measured. Insulin resistance index (IR) was calculated using the homeostasis model assessment method. Performance tests included a cardiopulmonary exercise test and knee extension strength and endurance measurements. RESULTS Patients with severe OSA had significantly (P<0.05) lower values of IMCL (14.1±5.4 AU) and EMCL (10.3±5.8 AU) compared to the control group (25.2±17.6 AU and 14.3±11.1 AU, respectively). Patients with severe OSA had significantly higher hsCRP, IR, and dyslipidemia compared with controls (all P<0.05). Furthermore, IMCL was negatively correlated with AHI, cumulative time with nocturnal pulse oximetric saturation lower than 90% (TSpO2<90%) (ρ=-0.35, P<0.05), IR (ρ=-0.40, P<0.05), glucose (ρ=-0.33, P<0.05), and insulin (ρ=-0.36, P<0.05), and positively correlated with lowest oximetric saturation (ρ=0.33, P<0.01). CONCLUSION Skeletal muscle dysfunction and metabolic abnormalities were observed in patients with OSA that did not have obesity. IMCL was positively correlated with aerobic capacity and muscular performance, but negatively correlated with AHI and IR. Large-scale clinical trials are required to explore the complicated mechanism among OSA, intramuscular metabolism, and insulin action. CLINICAL TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT00813852.
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Visceral obesity, skeletal muscle mass and resistin in metabolic syndrome development.
Rodríguez-López, CP, González-Torres, MC, Cruz-Bautista, I, Nájera-Medina, O
Nutricion hospitalaria. 2019;36(1):43-50
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Obesity is a growing public health problem at a national and global level. Visceral adipose tissue (VAT) is the most bioactive component that is related with the release of inflammatory mediators which gives rise to insulin resistance, mainly local, and subsequently in liver and skeletal muscle. The aim of this study was to determine the relationship of body components with the concentration of resistin as an inflammatory marker in patients with overweight and obesity. The study is an observational, cross-sectional clinical study which analysed 40 participants with an age range between 18 and 40 years. Results indicate that: - as body mass index and VAT increased, anthropometric measurements, body composition, and biochemical indicators were altered. - persons with obesity and increased VAT had the highest proportions of metabolic syndrome (MS). - an increase in skeletal muscle is related with increased BMI and with the presence of increased VAT. - there was a significant increase in resistin concentration in individuals without MS and increased VAT compared to those without MS and normal VAT. Authors conclude that resistin might be acting as an inflammatory adipocytokine [a bioactive product produced by adipose tissue], contributing to the increase in frequency of MS in those persons who present increased levels of this cytokine.
Abstract
INTRODUCTION Background: obesity implies an increase in the visceral adipose tissue (VAT), which is a risk factor for various metabolic diseases. VAT releases proinflammatory mediators, like resistin. In addition, it has been noted that the skeletal muscle mass (SMM) is involved in the development of metabolic syndrome (MS). Objective: this study was designed to determine the relationship of body components (VAT and SMM) with MS and resistin in patients with obesity. Methods: body composition and anthropometric and biochemical measurements to assess MS, and ELISA tests for resistin were carried out in 40 patients aged 18-40 years. Results: overweight and obesity were observed in 72% of patients; visceral obesity was found in 53% and 35% had MS. A positive correlation between VAT and SMM in patients with MS was detected. In the entire population, an increase of 1 kg of SMM was found to be associated with an increase of 3 cm2 of VAT, and an increase of 4 cm2 of VAT was observed in individuals with MS. According to resistin, people with increased VAT had higher concentration than persons with normal VAT. Furthermore, an increase of 1 cm2 of VAT accounted for a person entertaining a 3.3 fold greater risk of MS for different values of SMM and resistin. Conclusion: the transcendence and significance of VAT as a main factor in triggering the chronic inflammatory process and MS, the SMM and resistin were also related. INTRODUCCIÓN: Introducción: la obesidad implica un aumento del tejido adiposo visceral (TAV), el cual es un factor de riesgo para varias enfermedades metabólicas. El VAT se relaciona con mediadores proinflamatorios, como la resistina. Además, se ha observado que la masa musculoesquelética (MME) interviene en el desarrollo del síndrome metabólico (SM). Objetivo: este estudio fue diseñado para determinar la relación de la composición corporal (TAV y MME) con el SM y la resistina en pacientes con obesidad. Métodos: se realizaron medidas antropométricas, de composición corporal y bioquímica para determinar el SM y prueba de ELISA para resistina en 40 pacientes de 18 a 40 años de edad. Resultados: se observó sobrepeso y obesidad en el 72% de los participantes, obesidad visceral en el 53% y el 35% presentó SM. Se detectó una correlación positiva entre el TAV y la MME en pacientes con SM. En el grupo de estudio encontramos que un aumento de un 1 kg de MME se asociaba con un incremento de 3 cm2 de TAV y en individuos con SM, con un incremento de 4 cm2 de TAV. En relación con la resistina, las personas con TAV incrementado presentan concentraciones más altas que las personas con TAV normal. Además, se observó que un aumento de 1 cm2 de TAV representa un riesgo 3,3 veces mayor que para las personas de padecer SM para diferentes valores de MME y de resistina. Conclusión: además de la trascendencia y la importancia del TAV como factor principal para desencadenar el proceso inflamatorio crónico y el SM, se observó que la MME y la resistina también están relacionadas.
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Isocaloric Substitution of Dietary Carbohydrate Intake with Fat Intake and MRI-Determined Total Volumes of Visceral, Subcutaneous and Hepatic Fat Content in Middle-Aged Adults.
Meisinger, C, Rospleszcz, S, Wintermeyer, E, Lorbeer, R, Thorand, B, Bamberg, F, Peters, A, Schlett, CL, Linseisen, J
Nutrients. 2019;11(5)
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Obesity, a worldwide epidemic due to the availability of many unhealthy food options and limited physical exercise, is a known risk factor for many metabolic disorders. The aim of this study was to investigate the association of carbohydrate intake and isocaloric substitution with different types of fat as determined by magnetic resonance imaging (MRI). The study’s analysis was based on the KORA-FF4 study, the second follow-up study of the KORA Survey S4. A total of 400 individuals participated in the FF4 study, from which 283 participants were included in this analysis. Results indicate an association between fat accumulation at specific anatomic locations and macronutrient composition among the participants. The isocaloric substitution of carbohydrates with fat was associated with higher hepatic (related to the liver) fat content and visceral fat accumulation. Authors conclude that the study’s findings can contribute towards the long-lasting discussion about a diet’s optimal fat content.
Abstract
The present study investigated the association of carbohydrate intake and isocaloric substitution with different types of fat with visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT) and hepatic fat content as determined by magnetic resonance imaging (MRI). Data from 283 participants (mean age 56.1 ± 9.0 years) from the MRI sub study of the KORA FF4 study were included. VAT, SAT and total body fat were quantified by a volume-interpolated VIBE-T1w-Dixon MR sequence. Hepatic fat content was determined as the proton density fat-fraction (PDFF) derived from multiecho-T1w MR sequence. Dietary intake was estimated using information provided by two different instruments, that is, repeated 24-h food lists and a food frequency questionnaire. Replacing total carbohydrates with an isoenergetic amount of total fat was significantly positively associated with VAT and hepatic fat, while there was no significant association with SAT. The multivariable adjusted β-coefficient for replacing 5% of total energy (5E%) carbohydrates with total fat was 0.42 L (95% CI: 0.04, 0.79) for VAT. A substitution in total fat intake by 5E% was associated with a significant increase in liver fat content by 23% (p-value 0.004). If reproduced in prospective studies, such findings would strongly argue for limiting dietary fat intake.