Bioimpedance analysis of body composition in an international twin cohort

Energy and macronutrient intake heritability: A systematic review and meta-analysis of twin and family-based studies

BACKGROUND/AIMS

The current meta-analysis aimed to examine the heritability and familial resemblance of dietary intakes, including energy and macronutrients in both twin and family-based studies.

METHODS

The online literature databases, including PubMed, Scopus, and Web of Science were searched comprehensively until 2023 to identify the relevant studies. The heritability index in family studies was h2 and the heritability indices for twin studies were h2, A2, and E2. Three weighted methods were used to calculate the mean and SE of heritability dietary intakes.

RESULTS

Eighteen papers including 8 studies on familial population and 12 for twin population studies were included in the present meta-analysis. The heritability of dietary intakes in twin studies (range of pooled estimated h2, A2, and E2 was 30-55%, 14-42%, and 52-79%, respectively) was higher than family studies (range of pooled estimated h2 = 16-39%). In family studies, the highest and lowest heritability for various nutrients was observed for the fat (%Kcal) (h2 range:36-38%) and carbohydrate in g (h2 range:16-18%), respectively. In twin studies, based on mean h2, the highest and lowest heritability for various nutrients was reported for the fat (%Kcal) (h2 range:49-55%) and protein intake in g (h2 range:30-35%), respectively. Also, based on the mean of A2, the highest and lowest heritability was observed for carbohydrates (% Kcal) (A2 range:42-42%), and protein (% Kcal) (A2 range:14-16%), respectively. Furthermore, in twin studies, the highest and lowest mean of E2 was shown for saturated fats (E2 range:74-79%) and energy intake (E2 range:52-57%), respectively.

CONCLUSION

Our analysis indicated that both environmental factors and genetics have noticeable contributions in determining the heritability of dietary intakes. Also, we observed higher heritability in twins compared to family studies.

Genetic architecture of adiposity measures among Asians: Findings from GWAS

Adiposity has gradually become a global public threat over the years with drastic increase in the attributable deaths and disability adjusted life years (DALYs). Given an increased metabolic risk among Asians as compared to Europeans for any given body mass index (BMI) and considering the differences in genetic architecture between them, the present review aims to summarize the findings from genome-wide scans for various adiposity indices and related anthropometric measures from Asian populations. The search for related studies, published till February 2022, were made on PubMed and GWAS Catalog using search strategy built with relevant keywords joined by Boolean operators. It was recorded that out of a total of 47 identified studies, maximum studies are from Korean population (n = 14), followed by Chinese (n = 7), and Japanese (n = 6). Nearly 200 loci have been identified for BMI, 660 for height, 16 for weight, 28 for circumferences (waist and hip), 32 for ratios (waist hip ratio [WHR] and thoracic hip ratio [THR]), 5 for body fat, 16 for obesity, and 28 for adiposity-related blood markers among Asians. It was observed that though, most of the loci were unique for each trait, there were 3 loci in common to BMI and WHR. Apart from validation of variants identified in European setting, there were many novel loci discovered in Asian populations. Notably, 125 novel loci form Asian studies have been reported for BMI, 47 for height, 5 for waist circumference, and 2 for adiponectin level to the existing knowledge of the genetic framework of adiposity and related measures. It is necessary to examine more advanced adiposity measures, specifically of relevance to abdominal adiposity, a major risk factor for cardiometabolic disorders among Asians. Moreover, in spite of being one continent, there is diversity among different ethnicities across Asia in terms of lifestyle, climate, geography, genetic structure and consequently the phenotypic manifestations. Hence, it is also important to consider ethnic specific studies for identifying and validating reliable genetic variants of adiposity measures among Asians.

Genome-wide association study identifies genetic risk loci for adiposity in a Taiwanese population

Overweight and obese are risk factors for various diseases. In Taiwan, the combined prevalence of overweight and obesity has increased dramatically. Here, we conducted a genome-wide association study (GWAS) on four adiposity traits, including body-mass index (BMI), body fat percentage (BF%), waist circumference (WC), and waist-hip ratio (WHR), using the data for more than 21,000 subjects in Taiwan Biobank. Associations were evaluated between 6,546,460 single-nucleotide polymorphisms (SNPs) and adiposity traits, yielding 13 genome-wide significant (GWS) adiposity-associated trait-loci pairs. A known gene, FTO, as well as two BF%-associated loci (GNPDA2-GABRG1 [4p12] and RNU6-2-PIAS1 [15q23]) were identified as pleiotropic effects. Moreover, RALGAPA1 was found as a specific genetic predisposing factor to high BMI in a Taiwanese population. Compared to other populations, a slightly lower heritability of the four adiposity traits was found in our cohort. Surprisingly, we uncovered the importance of neural pathways that might influence BF%, WC and WHR in the Taiwanese (East Asian) population. Additionally, a moderate genetic correlation between the WHR and BMI (γg = 0.52; p = 2.37×10−9) was detected, suggesting different genetic determinants exist for abdominal adiposity and overall adiposity. In conclusion, the obesity-related genetic loci identified here provide new insights into the genetic underpinnings of adiposity in the Taiwanese population.

Association of body mass index and its long-term changes with cardiometabolic diseases: A nationwide twin study

BACKGROUND & AIMS

The association between higher body mass index (BMI) and cardiometabolic diseases (CMDs, including type 2 diabetes and cardiovascular diseases) is not well understood. We aimed to examine the association of BMI and its long-term changes with cardiometabolic diseases (CMDs) and explore the role of familial background and healthy lifestyle in this association.

METHODS

Within the Swedish Twin Registry, 36 622 CMD-free individuals aged ≥40 were followed for up to 16 years. BMI data was collected at baseline and 25-35 years prior to baseline. Healthy lifestyle (non-smoking, no/mild alcohol consumption, and regular physical activity) was assessed as unfavourable (none or only one of these factors) vs. favourable (two or three). Incident CMDs were identified by linkage with the Swedish National Patient Registry. Two strategies were followed: 1) Cox models in all twin individuals; 2) stratified Cox models in CMD-discordant twin pairs.

RESULTS

At baseline, 16 195 (44.2%) study participants had overweight/obesity (BMI ≥ 25 kg/m²) and 11 202 (30.6%) developed CMDs over follow-up. Among all participants, the hazard ratio (HR) and 95% confidence interval (CI) of developing any CMD was 1.52 (1.45-1.58) for people with overweight/obesity compared to normal BMI (20-25 kg/m²). Compared to stable normal BMI, HRs (95% CIs) of CMDs were 1.28 (1.02-1.59) and 1.33 (1.24-1.43) for only earlier life or only later life overweight/obesity, respectively, and 1.69 (1.55-1.85) for overweight/obesity both in earlier and later life. In stratified Cox analyses conducted among all CMD-discordant twin pairs, overweight/obesity was associated with greater risk of CMDs (1.37, 95% CI 1.18-1.61). In joint effect analysis, the risk of CMDs related to overweight/obesity was diminished 32% among people with a favourable lifestyle (1.51, 95% CI 1.44-1.58) compared to those with overweight/obesity and an unfavourable lifestyle (2.20, 95% CI 2.03-2.38).

CONCLUSIONS

Overweight/obesity is associated with an increased risk of CMDs, and shared genetic and early-life environmental factors might not account for this association. However, a favourable lifestyle could attenuate the risk of high BMI-related CMDs.

No Evidence for Passive Gene-Environment Correlation or the Influence of Genetic Risk for Psychiatric Disorders on Adult Body Composition via the Adoption Design

The relationship between genetic and environmental risk is complex and for many traits, estimates of genetic effects may be inflated by passive gene-environment correlation. This arises because biological offspring inherit both their genotypes and rearing environment from their parents. We tested for passive gene-environment correlation in adult body composition traits using the 'natural experiment' of childhood adoption, which removes passive gene-environment correlation within families. Specifically, we compared 6165 adoptees with propensity score matched non-adoptees in the UK Biobank. We also tested whether passive gene-environment correlation inflates the association between psychiatric genetic risk and body composition. We found no evidence for inflation of heritability or polygenic scores in non-adoptees compared to adoptees for a range of body composition traits. Furthermore, polygenic risk scores for anorexia nervosa, attention-deficit/hyperactivity disorder and schizophrenia did not differ in their influence on body composition traits in adoptees and non-adoptees. These findings suggest that passive gene-environment correlation does not inflate genetic effects for body composition, or the influence of psychiatric disorder genetic risk on body composition. Our design does not look at passive gene-environment correlation in childhood, and does not test for 'pure' environmental effects or the effects of active and evocative gene-environment correlations, where child genetics directly influences home environment. However, these findings suggest that genetic influences identified for body composition in this adult sample are direct, and not confounded by the family environment provided by biological relatives.

Heritability and Environmental Correlation of Phase Angle with Anthropometric Measurements: A Twin Study

Bioelectrical impedance analysis (BIA)-derived phase angle (PhA) is a valuable parameter to assess physical health. However, the genetic and environmental aspects of PhA are not yet well understood. The present study aimed to estimate the heritability of PhA and investigate the relationships between PhA and anthropometric measurements. PhA and skeletal muscle mass index (SMI) were examined using multi-frequency BIA in 168 Japanese twin volunteers (54 males and 114 females; mean age = 61.0 ± 16.5 years). We estimated the narrow-sense heritability of these parameters and the genetic and environmental relationships between them using a genetic twin modeling. For the PhA, 51% (95% confidence interval: 0.33, 0.64) of the variance was explained by additive genetic effects, and 49% (95% confidence interval: 0.36, 0.67) was explained by unique environmental effects. The heritability of PhA was lower than the height, body weight, and body mass index. PhA shared almost no genetic variation with anthropometric measurements and SMI but shared an environmental variation (14%) with SMI. These findings suggest that the genes affecting PhA are different than those affecting anthropometric measurements and SMI. The correlation between PhA and SMI is caused by common environmental factors.

Obstructive sleep apnea and hypertriglyceridaemia share common genetic background: Results of a twin study

Obstructive sleep apnea is associated with an increased risk of hypertension, diabetes and dyslipidaemia. Both obstructive sleep apnea and its comorbidities are at least partly heritable, suggesting a common genetic background. Our aim was to analyse the heritability of the relationship between obstructive sleep apnea and its comorbidities using a twin study. Forty-seven monozygotic and 22 dizygotic adult twin pairs recruited from the Hungarian Twin Registry (mean age 51 ± 15 years) attended an overnight diagnostic sleep study. A medical history was taken, blood pressure was measured, and blood samples were taken for fasting glucose, total cholesterol, triglyceride, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol and lipoprotein (a). To evaluate the heritability of obstructive sleep apnea and its comorbidities bivariate analysis was performed with an adjustment for age, gender, body mass index (BMI) and smoking after false discovery rate correction and following exclusion of patients on lipid-lowering and antidiabetic medications. There was a significant correlation between indices of obstructive sleep apnea severity, such as the apnea-hypopnea index, oxygen desaturation index and percentage of sleep time spent with oxygen saturation below 90%, as well as blood pressure, serum triglyceride, lipoprotein (a) and glucose levels (all p < .05). The bivariate analysis revealed a common genetic background for the correlations between serum triglyceride and the oxygen desaturation index (r = .63, p = .03), as well as percentage of sleep time spent with oxygen saturation below 90% (r = .58, p = .03). None of the other correlations were significantly genetically or environmentally determined. This twin study demonstrates that the co-occurrence of obstructive sleep apnea with hypertriglyceridaemia has a genetic influence and heritable factors play an important role in the pathogenesis of dyslipidaemia in obstructive sleep apnea.

Genetic correlations of psychiatric traits with body composition and glycemic traits are sex- and age-dependent

Body composition is often altered in psychiatric disorders. Using genome-wide common genetic variation data, we calculate sex-specific genetic correlations amongst body fat %, fat mass, fat-free mass, physical activity, glycemic traits and 17 psychiatric traits (up to N = 217,568). Two patterns emerge: (1) anorexia nervosa, schizophrenia, obsessive-compulsive disorder, and education years are negatively genetically correlated with body fat % and fat-free mass, whereas (2) attention-deficit/hyperactivity disorder (ADHD), alcohol dependence, insomnia, and heavy smoking are positively correlated. Anorexia nervosa shows a stronger genetic correlation with body fat % in females, whereas education years is more strongly correlated with fat mass in males. Education years and ADHD show genetic overlap with childhood obesity. Mendelian randomization identifies schizophrenia, anorexia nervosa, and higher education as causal for decreased fat mass, with higher body fat % possibly being a causal risk factor for ADHD and heavy smoking. These results suggest new possibilities for targeted preventive strategies.

Genomics of body fat percentage may contribute to sex bias in anorexia nervosa

Anorexia nervosa (AN) occurs nine times more often in females than in males. Although environmental factors likely play a role, the reasons for this imbalanced sex ratio remain unresolved. AN displays high genetic correlations with anthropometric and metabolic traits. Given sex differences in body composition, we investigated the possible metabolic underpinnings of female propensity for AN. We conducted sex-specific GWAS in a healthy and medication-free subsample of the UK Biobank (n = 155,961), identifying 77 genome-wide significant loci associated with body fat percentage (BF%) and 174 with fat-free mass (FFM). Partitioned heritability analysis showed an enrichment for central nervous tissue-associated genes for BF%, which was more prominent in females than males. Genetic correlations of BF% and FFM with the largest GWAS of AN by the Psychiatric Genomics Consortium were estimated to explore shared genomics. The genetic correlations of BF%male and BF%female with AN differed significantly from each other (p < .0001, δ = -0.17), suggesting that the female preponderance in AN may, in part, be explained by sex-specific anthropometric and metabolic genetic factors increasing liability to AN.

Genetic influences on the onset of obstructive sleep apnoea and daytime sleepiness: a twin study

Background

Obstructive sleep apnoea (OSA) is one of the major sources of the excessive daily sleepiness, cognitive dysfunction, and it increases cardiovascular morbidity and mortality. Previous studies suggested a possible genetic influence, based on questionnaires but no objective genetic study was conducted to understand the exact variance underpinned by genetic factors.

Methods

Seventy-one Hungarian twin pairs involved from the Hungarian Twin Registry (48 monozygotic, MZ and 23 dizygotic, DZ pairs, mean age 51 ± 15 years) underwent overnight polysomnography (Somnoscreen Plus Tele PSG, Somnomedics GMBH, Germany). Apnoea hypopnea index (AHI), respiratory disturbance index (RDI) and oxygen desaturation index (ODI) were registered. Daytime sleepiness was measured with the Epworth Sleepiness Scale (ESS). Bivariate heritability analysis was applied.

Results

The prevalence of OSA was 41% in our study population. The heritability of the AHI, ODI and RDI ranged between 69% and 83%, while the OSA, defined by an AHI ≥5/h, was itself 73% heritable. The unshared environmental component explained the rest of the variance between 17% and 31%. Daytime sleepiness was mostly determined by the environment, and the variance was influenced in 34% by the additive genetic factors. These associations were present after additional adjustment for body mass index.

Conclusion

OSA and the indices of OSA severity are heritable, while daytime sleepiness is mostly influenced by environmental factors. Further studies should elucidate whether close relatives of patients with OSA may benefit from early family risk based screening.

Heritability of muscle mass in Korean parent-offspring pairs in the Fifth Korean National Health and Nutrition Examination Survey (KNHANES V)

OBJECTIVES

Decreased muscle mass is known to be associated with several serious medical conditions. We analyzed the Fifth Korean National Health and Nutrition Examination Survey (KNHANES V, 2010-2011) to estimate the heritability of muscle mass in Korean parent-offspring pairs.

STUDY DESIGN

Cross-sectional.

MAIN OUTCOME MEASURES

A total of 1233 parents (average age 57.67 ± 8.50 years) and 917 offspring (average age 29.10 ± 7.57 years) from 743 families were included in the analysis. Muscle mass was estimated based on three different indices: appendicular skeletal muscle mass (ASM) measured with a dual-energy X-ray absorptiometry (DXA), weight-adjusted ASM (SMI), and height-adjusted ASM (RASM). The heritability was estimated by employing the maximum-likelihood variance components implemented in Sequential Oligogenic Linkage Analysis Routines (SOLAR). The best-fitting model was determined out of four polygenic models. Pearson's partial correlation coefficient was also calculated using the muscle mass indices to further study the association between father or mother and son or daughter pairs.

RESULTS

The heritability estimates of the muscle mass indices ranged from 55% to 80% (all p < 0.01). The correlation coefficient of father and offspring ranged from 0.11 to 0.40, while that of mother and offspring ranged from 0.23 to 0.43 (all p < 0.01).

CONCLUSIONS

The heritability estimates of muscle mass in Koreans are large and significant, suggesting that parental muscle mass is an important predictor of the offspring's muscle mass. The result implies that there may be a genetic factor partly determining muscle mass.

Assessing genetic and environmental influences on epicardial and abdominal adipose tissue quantities: a classical twin study

BACKGROUND/OBJECTIVES

Various adipose tissue compartments play an important role in the development of cardiometabolic diseases. The quantity of different fat compartments is influenced by genetic and environmental factors. The aim of our study was to evaluate the magnitude of genetic and environmental effects on epicardial, subcutaneous and visceral adipose tissue (EAT, SAT and VAT) quantities in a cohort of adult twin pairs.

SUBJECTS/METHODS

In this cross-sectional study we investigated adult twins (57 monozygotic (MZ) and 33 dizygotic (DZ) same-gender twin pairs; 180 twin subjects). We measured EAT volume using electrocardiogram-gated native computed tomography (CT) scan of the heart, and abdominal SAT and VAT areas were quantified between the third and fourth lumbar vertebra on native CT images. We calculated genetic and environmental impact on the size of various adipose tissue compartments by analyzing co-twin correlations in MZ and DZ pairs separately, and furthermore by using genetic structural equation models.

RESULTS

In co-twin analysis, MZ twins had stronger correlations than DZ twins for EAT (r_MZ=0.81, r_DZ=0.32), similar to SAT and VAT quantities (r_MZ=0.80, r_DZ=0.68 and r_MZ=0.79, r_DZ=0.48, respectively). In multi-trait model fitting analysis, the overall contribution of genetic factors to EAT, SAT and VAT volumes were 80%, 78% and 70%, whereas environmental factors were 20%, 22% and 30%, respectively. Common pathway model analyses indicated that none of the EAT, SAT and VAT phenotypes was independent of the other two.

CONCLUSIONS

Genetic factors have substantial influence, while environmental factors have only a modest impact on EAT volume, abdominal SAT and VAT quantities. There is a considerable amount of common genetic background influencing the quantities of all three adipose tissue compartments.

Fat mass, fat-free mass, and resting metabolic rate in weight-stable sleeve gastrectomy patients compared with weight-stable nonoperated patients

BACKGROUND

There is evidence that body composition and resting metabolic rate (RMR) in weight-stable patients after Roux-en-Y gastric bypass and duodenal switch is similar to that of nonoperated individuals within the same body mass index (BMI) interval. Currently, data concerning fat mass (FM), fat-free mass (FFM), and RMR on weight-stable patients after sleeve gastrectomy (SG) are lacking.

OBJECTIVES

To assess FM, FFM, and RMR, in a selected and homogenous population of weight-stable SG patients (WSSG) and compare them with those obtained from healthy normal weight-stable nonoperated (WSNO) volunteers controls of similar sex, age, and BMI.

SETTING

University hospital, Italy.

METHODS

We assessed total weight, FM, and FFM by bioelectrical impedance assay, and RMR by indirect calorimetry, in 70 WSSG patients (47 females, 23 males) at a mean follow-up of 3.2 ± 2.1 years after SG and compared them with 70 healthy WSNO volunteers, as controls (47 females, 23 males).

RESULTS

There was no significant difference between WSSG and WSNO groups concerning total weight (males, 72 ± 2.66 versus 72.8 ± 1.99 kg, P = .0254; females 65.1 ± 2.53 versus 63.7 ± 2.87 kg, P = .0139), FM (males, 17.7 ± 1.53 versus 16.7 ± 1.57 kg, P = .0341; females 19.6 ± 0.50 versus 18.5 ± 2.85 kg, P = .0104), FFM (males, 54.3 ± 3.07 versus 56.1 ± 3.30 kg; P = .049; females 45.5 ± 2.29 versus 45.1 ± 1.13 kg, P = .287), and RMR (males, 1541 ± 121.3 versus 1463 ± 74.4 kcal/d; P = .0118; females 1214 ± 54.9 versus 1250 ± 90.1 kcal/d, P = .0215).

CONCLUSION

At a mean follow-up of 3.2 ± 2.1 years after SG, WSSG patients of both sexes have a FM, FFM, and RMR comparable to that of healthy WSNO individuals within the same age and BMI interval. These findings further support bariatric surgery-induced weight loss as a physiologic process and indicate that young patients, in the setting of an adequate preoperative and postoperative specific diet and moderate physical activity, do not suffer from excessive FFM depletion after SG in the mid-term.

Obesity: systemic and pulmonary complications, biochemical abnormalities, and impairment of lung function

Obesity is currently one of the major epidemics of this millennium and affects individuals throughout the world. It causes multiple systemic complications, some of which result in severe impairment of organs and tissues. These complications involve mechanical changes caused by the accumulation of adipose tissue and the numerous cytokines produced by adipocytes. Obesity also significantly interferes with respiratory function by decreasing lung volume, particularly the expiratory reserve volume and functional residual capacity. Because of the ineffectiveness of the respiratory muscles, strength and resistance may be reduced. All these factors lead to inspiratory overload, which increases respiratory effort, oxygen consumption, and respiratory energy expenditure. It is noteworthy that patterns of body fat distribution significantly influence the function of the respiratory system, likely via the direct mechanical effect of fat accumulation in the chest and abdominal regions. Weight loss caused by various types of treatment, including low-calorie diet, intragastric balloon, and bariatric surgery, significantly improves lung function and metabolic syndrome and reduces body mass index. Despite advances in the knowledge of pulmonary and systemic complications associated with obesity, longitudinal randomized studies are needed to assess the impact of weight loss on metabolic syndrome and lung function.

Genetic and environmental influence on thyroid gland volume and thickness of thyroid isthmus: a twin study

OBJECTIVES

Decreased thyroid volume has been related to increased prevalence of thyroid cancer.

SUBJECTS AND METHODS

One hundred and fourteen Hungarian adult twin pairs (69 monozygotic, 45 dizygotic) with or without known thyroid disorders underwent thyroid ultrasound. Thickness of the thyroid isthmus was measured at the thickest portion of the gland in the midline using electronic calipers at the time of scanning. Volume of the thyroid lobe was computed according to the following formula: thyroid height*width*depth*correction factor (0.63).

RESULTS

Age-, sex-, body mass index- and smoking-adjusted heritability of the thickness of thyroid isthmus was 50% (95% confidence interval [CI], 35 to 66%). Neither left nor right thyroid volume showed additive genetic effects, but shared environments were 68% (95% CI, 48 to 80%) and 79% (95% CI, 72 to 87%), respectively. Magnitudes of monozygotic and dizygotic co-twin correlations were not substantially impacted by the correction of covariates of body mass index and smoking. Unshared environmental effects showed a moderate influence on dependent parameters (24-50%).

CONCLUSIONS

Our analysis support that familial factors are important for thyroid measures in a general twin population. A larger sample size is needed to show whether this is because of common environmental (e.g. intrauterine effects, regional nutrition habits, iodine supply) or genetic effects.

Clinical impact of Mediterranean-enriched-protein diet on liver size, visceral fat, fat mass, and fat-free mass in patients undergoing sleeve gastrectomy

BACKGROUND

Weight loss before laparoscopic sleeve gastrectomy (LSG) is desirable because it can reduce visceral fat and liver size thereby facilitating the surgical procedure. Preoperative very-low-energy diets have been demonstrated to decrease weight, visceral fat, and liver size. However, no studies have been conducted using the Mediterranean-protein-enriched diet (MPED) or on the amount of preoperative weight loss attributed to the loss of fat-free mass (FFM).

OBJECTIVES

To evaluate the effect of the MPED on weight, visceral fat, liver size, fat mass (FM), and FFM in obese patients undergoing LSG.

SETTING

University Hospital, Italy.

MATERIALS AND METHODS

Obese male patients (n = 37) with a mean body mass index (BMI) of 45.2 kg/m(2) scheduled for LSG underwent an 8-week preoperative MPED. Their weight, visceral fat, body composition, liver size, and biochemical and metabolic patterns were measured before and after the diet. Patient compliance was assessed by the presence of ketonuria and weight loss. Qualitative methods (5-point Likert questionnaire) were used to measure diet acceptability and side effects.

RESULTS

We observed highly significant decreases in weight, liver size, visceral fat, and FM; however, there was no significant reduction in FFM. All tested patients showed a high frequency of acceptability and compliance in following the diet, and no secondary effects were observed.

CONCLUSION

Based on our findings, we were able to support the hypothesis that MPED might be associated with significant reductions in weight loss, FM, and liver size without a significant loss of FFM.