The agreement between body composition indices measured by dual-energy X-Ray absorptiometry and bioelectrical impedance analysis in adults.

Bioelectrical impedance analysis (BIA), a device that analyzes the current conduction differences between the fat and water components is widely used for reasons that include convenience of use, non-invasiveness, safety, and low cost. Dual energy X-ray absorptiometry (DXA) allows for the assessment of total body and regional lean and fat tissues and bone mineral content (BMC). The objective of this study was to compare body composition assessments by BIA and DXA before and after a 6-week herbal diet intervention program in 50 pre-menopausal women [mean +/- SD: age 30.58 +/- 6.15, body mass index (BMI) 31.72 +/- 3.78]. Waist-to-hip ratio (WHR) was measured by BIA and anthropometry. Lean body mass (LBM), body fat (BF), BMC and percent body fat (%BF) were measured by BIA and DXA. Highly significant correlations were observed between BIA and DXA measurements for LBM, BF, BMC and %BF (r = 0.73, 0.93, 0.53, 0.79, respectively) before the intervention. Differences between BIA and DXA measurements were observed in LBM, BF, %BF and BMC before intervention (p < 0.01) where WHR by BIA was significantly higher compared to anthropometry before (p < 0.01) and after the intervention (p < 0.01). BIA underestimated LBM by 1.85 kg and overestimated BF by 2.54 kg compared to DXA before the intervention. Although BIA and DXA showed highly significant correlations for LBM, BF, BMC and %BF before the intervention, they did not produce statistically comparable results in pre-menopausal Korean women and therefore should not be used interchangeably when measuring body composition.

Body composition analysis is a valuable tool for assessing and monitoring the nutritional status of children with spinal muscular atrophy (SMA). This study was designed to compare the consistency of bioelectrical impedance analysis (BIA) and dual-energy X-ray absorptiometry (DXA), as the gold standard method for assessing body composition in clinical practice when treating children with type II and III SMA. From 2019 to 2021, we performed a retrospective analysis of body composition by DXA and BIA measurement methods in patients with type II and III SMA treated at a Chinese tertiary children's hospital. Fat mass (FM), muscle mass (MM), bone mineral content (BMC), and visceral fat area (VFA) were compared using paired sample t-tests. We calculated Lin's concordance correlation coefficient (CCC) and Spearman correlation coefficient to verify the correlation between DXA and BIA measurements. Bland-Altman analysis was used to assess the consistency of the two methods. Fifty-seven children with type II and III SMA were recruited. Compared with body composition measured by DXA, the average FM measured by BIA is significantly lower (P <0.001), whereas the average MM, BMC, and VFA measured by BIA are significantly higher (P < 0.001) in children with SMA. Overall, the difference between MM (Delta [BIA-DAX] = 1.6 kg) and FM (Delta [BIA-DAX] = -1.6 kg) measured by DXA and BIA was minor, whereas the difference of VFA (Delta [BIA-DAX] = -43.5 cm) was significantly large. Correlation analysis indicated a substantial correlation of MM (CCC = 0.96 [95% confidence interval (CI) = 0.93-0.98], r = 0.967 [P < 0.0001]) and FM (CCC = 0.95 [95% CI = 0.92-0.97], r = 0.953 [P < 0.0001]), and poor correlation of BMC (CCC = 0.61 [95% CI = 0.42-0.75], r = 0.612 [P < 0.0001]) and VFA (CCC = 0.54 [95% CI = 0.33-0.70], r = 0.689 [P < 0.0001]) measurements between the two methods. The Bland-Altman analysis suggests that the majority of participants were within LOA. In addition, differences in MM and VFA measurements between BIA and DAX increased according to patients' increasing height, whereas differences in FM and BMC did not differ with height. BIA overestimates MM and underestimates the FM, BMC, and VFA in children with SMA compared with DXA measurements. Overall, the non-invasive, easy-to-use, and repeatable BIA measurements were found to be in good agreement with DXA measurements, especially for FM and MM, which are essential parameters for the nutritional evaluation of children with SMA.

ABSTRACTWe aimed to assess the agreement of a commercially available bioelectrical impedance analysis (BIA) device in measuring changes in fat, lean and bone mass over a 10-week lifestyle intervention, with dual energy X-ray absorptiometry (DXA) as reference. A sample of 136 volunteers (18–66 years) underwent a physical activity intervention to enhance lean mass and reduce fat mass. BIA (Tanita BC545) and DXA (Hologic Explorer) measures of whole-body composition were taken at baseline and at the end of the intervention. After an average of 74 ± 18 days intervention, DXA showed significant changes in 2 of 3 outcome variables: reduced fat mass of 0.802 ± 1.092 kg (P < 0.001), increased lean mass of 0.477 ± 0.966 kg (P < 0.001); minor non-significant increase of 0.007 ± 0.041 kg of bone mass (P = 0.052). The respective changes in BIA measures were a significant reduction of 0.486 ± 1.539 kg fat (P < 0.001), but non-significant increases of 0.084 ± 1.201 kg lean mass (P = 0.425), and 0.014 ± 0.091 kg bone (P = 0.074). Significant, but moderately weak, correlations were seen in absolute mass changes between DXA and BIA: 0.511 (fat), 0.362 (lean) and 0.172 (bone). Compared to DXA, BIA demonstrated mediocre agreement to changes in fat mass, but poor agreement to lean mass changes. BIA significantly underestimated the magnitude of changes in fat and lean mass compared to DXA.

Modern bioelectrical impedance analysis (BIA) provides a wide range of body composition estimates such as fat mass (FM), lean body mass (LBM), and body water, using specific algorithms. Assuming that the fat free mass (FFM) and LBM can be accurately estimated by the 8-electrode BIA analyzer (BIA8MF; InBody230, Biospace), the bone mineral content (BMC) may be calculated by subtracting the LBM from the FFM estimates based on the three-compartment (3C) model. In this cross-sectional study, 239 healthy Taiwanese adults (106 male and 133 female) aged 20–45 years were recruited for BIA and dual-energy X-ray absorptiometry (DXA) measurements of the whole body and body segments, with DXA as the reference. The results showed a high correlation between BIA8MF and DXA in estimating total and segmental LBM, FM and percentage body fat (r = 0.909–0.986, 0.757–0.964, and 0.837–0.936, respectively). For BMC estimates, moderate to high correlations (r = 0.425–0.829) between the two methods were noted. The percentage errors and pure errors for BMC estimates between the methods ranged from 33.9% to 93.0% and from 0.159 kg to 0.969 kg, respectively. This study validated that BIA8MF can accurately assesses LBM, FM and body fat percentage (BF%). However, the estimation of segmental BMC based on the difference between FFM and LBM in body segments may not be reliable by BIA8MF.

Determinants of body composition measured by dual-energy X-ray absorptiometry in Dutch children and adolescents

To validate body composition measurements by Bioelectric Impedance Analysis (BIA) against Dual-Energy X-ray Absorptiometry (DXA) as the reference method in healthy children and adolescents. Cross-sectional. Schools in and around Pune city, India. A random sample of 210 (114 boys, 96 girls) apparently healthy Indian children and adolescents (5-18 y). Weight, height, Tanner stage (TS) were recorded. Body composition measures: fat-free mass (FFM), fat mass (FM), lean mass (LM), bone mineral content (BMC) and body fat percentage (%BF) were assessed by BIA and DXA on a single day. Agreement between the methods was estimated by Pearson's correlation, and Bland and Altman analysis. %BF, FM, FFM, LM, BMC. BIA underestimated %BF by 6.7 (3.7)% as compared to DXA. Mean FFM, BMC and LM by BIA were significantly higher than by DXA (P<0.001). These differences remained similar after adjusting for age, BMI and TS. Mean differences between FFM (-2.32 (1.39) kg), BMC (-0.18 (0.15) kg), and LM (-2.15 (1.34) kg) by DXA and BIA were significant (P<0.01). Correlations between BIA and DXA were 0.92 for %BF, 0.96 for LM and 0.98 for FFM and BMC. Both the methods were similar in identifying normal and overfat children as per their respective cut-offs. BIA and DXA techniques are not interchangeable for assessment of body composition. However, BIA may be used in the field/clinical setting preferably with ethnicity specific references.

To compare the consistency in the measurement of percentage of body fat (PBF) by multi-frequency bioelectrical impedance analysis (MF-BIA) and dual energy X-ray absorptiometry (DXA) in overweight and obese adults in China, and provide evidence for the accurate MF-BIA application in China. A total of 1 323 overweight/obese adults aged 22-55 years were recruited in this study. All the subjects received PBF measurement by both MF-BIA and DXA. The consistency in PBF measurement by MF-BIA and DXA was evaluated by using interclass correlation coefficients (ICC), then the correction prediction models was established. The differences in PBF measurement in male subjects and female subjects between MF-BIA and DXA were statistical significant (all P < 0.01), the mean difference values were -6.5% for overweight males and -4.3% for obese males, -2.5% for overweight females and 0.5% for obese females, respectively. The difference in ICC of PBF between MF-BIA and DXA measurement were statistically significant in all subgroups (P < 0.01). The ICC was 0.746 for overweight males, 0.807 for obese males, 0.628 for overweight females and 0.674 for obese females, respectively. The correction prediction models included: PBF (DXA) = 13.425 + 0.719 × PBF (MF-BIA) for overweight males; PBF (DXA) = 12.572 + 0.741 × PBF (MF-BIA) for obese males; PBF (DXA) = 9.785 + 0.802 × PBF (MF-BIA) for overweight females; PBF (DXA) = 20.348 + 0.532 × PBF (MF-BIA) for obese females. The consistency in PBF measurement in overweight/obese adults by MF-BIA and DXA was poor in China. Correction should be conducted when MF-BIA is used in the measurement of PBF.

To assess sarcopenia, sarcopenic obesity, physical performance in patients with acromegaly and compare the diagnostic performance of dual-energy X-ray absorptiometry (DXA) and multifrequency bioelectrical impedance analysis (BIA). This cross-sectional study included 27 patients with acromegaly and 27 age-, sex-, and BMI-matched patients without acromegaly. Body composition was assessed using BIA and DXA. Lean mass indices included fat-free mass index (FFMI) and skeletal muscle index (SMI) via BIA, and the Baumgartner (BMG) and Foundation for the National Institutes of Health indices via DXA. Obesity parameters included fat mass index (FMI) and body fat percentage via BIA. Physical performance was evaluated using handgrip strength (HGS), Timed Up and Go (TUG), 4-m gait speed (4MGS), and the Short Physical Performance Battery (SPPB) tests. The strength, assistance in walking, rising from a chair, climbing stair and falls (SARC-F) questionnaire was also performed. Strong correlations were observed between BIA and DXA body composition measures (r = 0.83, p < 0.01 for %BIA fat mass vs. %DXA fat mass; r = 0.80, p < 0.01 for SMI vs. BMG and r = 0.80, p < 0.01 for FFMI vs. BMG). Patients with acromegaly had significantly higher FFMI than patients without the disease (p = 0.03), but no difference in sarcopenic obesity prevalence (p = 0.50). Patients with acromegaly performed worse in the TUG and 4MGS tests, even after adjustment for confounders (p < 0.01 for both). No significant associations were found between SARC-F scores and lean mass or physical performance. Patients with acromegaly showed impaired physical performance despite higher FFMI, with no differences in sarcopenic obesity. The SARC-F questionnaire showed limited diagnostic value in this population.

The evaluation of body composition is an essential parameter for preventing obesity and sarcopenic obesity, which are prognostic factors in breast cancer. This study aims to validate the bioelectrical impedance analysis (BIA) of women who are breast cancer survivors by using the dual-energy x-ray absorptiometry (DXA) measurement method. This validation study included 104 women without metastasis between 32 and 72 years old (mean 47.03 ± 8.59) whose treatment was completed 6 months prior. Body composition analysis was performed sequentially using both measurements and when participants were hungry. Meaningful differences were found in fat-free mass (FFM) (BIA: 46.57 ± 5.54 kg; DXA: 41.06 ± 5.11 kg), body fat percentage (%BF) (BIA: 34.28% ± 6.24%; DXA: 43.91% ± 5.58%), body fat mass (FM) (BIA: 25.37 ± 8.84 kg; DXA: 31.24 ± 9.09 kg), and lean soft tissue mass (LSTM) (BIA: 4.42 ± 5.66 kg; DXA: 38.75 ± 4.98 kg) (P < 0.001). Powerful associations for body FM and strong associations for other parameters were seen. A constant and/or proportional error was found between the two devices within the direction of strong and solid components. Compared with DXA, the BIA measurement gives a lower estimate of %BF and FM and a higher estimate of LSTM and FFM. By the mathematical relationship between the two measurement methods, it seems possible to adapt the body composition parameters obtained from BIA of patients with breast cancer to DXA results. In the future, there will be a need to evaluate these two devices with more extensive studies.

Duchenne muscular dystrophy (DMD) patients have a lower percentage of total body water and higher extracellular water to intracellular water (ECW/ICW) ratio compared with normal subjects. However, it is not known whether this is due to increased fat mass or a decreased amount of ICW in muscle cells in DMD patients. The purpose of this study was to (1) determine the effect of increased fat mass and decreased lean mass on the ECW to ICW ratio in DMD patients and to (2) determine the validity of multifrequency bioelectrical impedance analysis (MFBIA) in assessing body composition in DMD patients. This study has a quasi-experimental, comparative design using nonequivalent groups. A total of 46 boys ranging from 6 to 13 yrs of age participated in this study. There were 12 nonobese able-bodied controls, 19 obese able-bodied children (obese), and 15 boys with DMD. Body composition was measured by dual-energy x-ray absorptiometry (DEXA). Body composition and body water compartment analysis were assessed by MFBIA. All measurements obtained using MFBIA were compared with those obtained using DEXA for validation. Both MFBIA and DEXA measures were strongly correlated in control (r = 0.99), obese (r = 0.92), and DMD subjects (r = 0.95). However, lean tissue mass measured by DEXA in the DMD subjects was only slightly higher (19.2 +/- 1.1 vs. 18.2 +/- 1.2, P < 0.02) than as measured by MFBIA. Mean percentage of body fat measured by DEXA in the DMD subjects (30.4 +/- 3.1%) was significantly lower than as measured by MFBIA (38.7 +/- 2.2%). The mean percentage of body fat measured by DEXA in the control group (23.2 +/- 1.8%) was significantly (P < 0.001) lower than as measured by MFBIA (28.6 +/- 1.6%). The mean percentage of body fat measured by DEXA in obese able-bodied controls (40.8 +/- 0.9%) was not significantly different from that measured by MFBIA (40.4 +/- 1.5%). Compared with the obese and control subjects, DMD subjects showed reduced ICW and ECW, with an increased ECW/ICW ratio, as expected. However, the percentage of fat for the DMD group was not different from the obese group. DMD patients have elevated ECW/ICW ratios compared with obese subjects and nonobese controls. However, obese subjects and nonobese controls had similar ECW/ICW ratios, despite the increased fat tissue mass in obese subjects. This suggests that the elevated ECW/ICW ratios in DMD subjects are not due to increased fat mass but rather some other mechanism, likely impaired cellular homeostasis due to muscle membrane instability. Although MFBIA slightly underestimates lean tissue mass in boys with DMD, it has a potential role as an inexpensive and easy to use measurement tool to measure changes in muscle mass in the clinical setting.

Background Precise assessment of body composition is critical for managing obesity and sarcopenia, both of which are rising health concerns around the globe. While dual-energy X-ray absorptiometry (DXA) remains the gold standard, its high cost and limited accessibility hinder large-scale application. Multi-frequency bioelectrical impedance analysis (MF-BIA) shows promise as an alternative method, but validation in specific populations remains necessary. Objectives This study aimed to validate and evaluate the diagnostic accuracy of the InBody 970S MF-BIA device in estimating body composition parameters against DXA among healthy Malaysian adults. Methods A prospective validation study was conducted among 148 healthy adults aged 20–45 years. Participants underwent standardised assessments using MF-BIA (InBody 970S) and full-body DXA. Linear regression, paired t-tests, Bland–Altman plots, and diagnostic performance indices (sensitivity, specificity, PPV, NPV) were used to evaluate the agreement between methods for fat mass (BFM), lean body mass (LBM), fat-free mass (FFM), percent body fat (PBF), bone mineral content (BMC), and skeletal muscle mass index (SMI). Results MF-BIA showed strong correlations with DXA across all parameters (R 2 = 0.72–0.97). The predictive models for BFM, LBM, and PBF demonstrated high accuracy (e.g., BFM: R 2 = 0.96; LBM: R 2 = 0.96; FFM: R 2 = 0.97). Diagnostic agreement was particularly strong for sarcopenia (sensitivity = 95.1%, NPV = 98.0%) and obesity classification (specificity and PPV = 100%), though obesity sensitivity was lower (75.2%). Bland–Altman analysis confirmed acceptable limits of agreement. Conclusion MF-BIA offers a clinically valid, non-invasive, and accessible method for body composition assessment in Malaysian adults. Its utility in identifying obesity and sarcopenia risk supports its integration into routine clinical practice and public health screening, especially in resource-limited settings. Future work should explore ethnic-specific calibration to enhance its diagnostic precision across diverse populations.

Pilates is a popular type of exercise, aimed at improving core muscle strength and endurance, core stability, and joint flexibility through a variety of whole-body exercises. Research has shown that Pilates improves body composition, muscle endurance, and joint flexibility. Adequate protein intake is a key factor in supporting the adaptive response of skeletal muscle to exercise training. However, whether protein supplementation augments the adaptations to Pilates training remains unknown. Thus, the aim of the present study was to investigate the effects of protein supplementation during Pilates training on body composition, core muscle endurance, and joint flexibility in trained women. Nineteen Pilates-trained women (31 ± 9 y) performed 10 weeks of Pilates training using the Reformer and Cadillac apparatuses, at least 2 times per week. Participants were randomly allocated to either a placebo (n = 10) or protein supplementation group (n = 9) in a quadruple-blind (participants, intervention providers, investigators, and outcome assessors) design. Participants received 0.6 g of maltodextrin or whey protein per kg body weight daily, respectively. Habitual dietary intake was monitored throughout the study. Before and after the intervention, anthropometric measures (body weight, body mass index, waist and hip circumferences), body composition [through full-scan dual-energy X-ray absorptiometry (DXA) and multifrequency bioelectrical impedance analysis (BIA)], core muscle endurance (through the McGill's torso muscular endurance test battery), and joint flexibility (through the sit-and-reach test) were assessed. Data were analyzed by 2-way ANOVA (supplement × time) with repeated measures on time. Common DXA and BIA variables (whole-body fat and lean mass) were compared through paired Student's t tests and subjected to Pearson's correlation analysis. The level of statistical significance was set at α = 0.05. Participants received, on average, 1.3 g protein/kg body weight/day from their habitual diet. After 10 weeks of Pilates training and regardless of supplementation, body fat (assessed by BIA) and hip circumference decreased; lean mass, total water, and extracellular water (by BIA) increased; and arm lean mass, trunk bone mineral content, and trunk bone area (by DXA) increased (all p < 0.05). The common BIA and DXA variables were highly correlated (r > 0.78, p < 0.001) and did not differ pre-intervention (p > 0.1), although they differed post-intervention (p < 0.001), with BIA overestimating lean mass compared with DXA. Core muscle endurance and joint flexibility increased with training (p < 0.05), with no effect of supplementation. Ten weeks of Pilates training improved core muscle endurance, joint flexibility, and aspects of body composition in healthy trained women, but these adaptations were not enhanced by daily supplementation with 0.6 g of protein per kilogram body weight.

Objective To establish diagnostic standard of sarcopenia using bioelectrical impedance analysis (BIA) and to obtain the prevalence of sarcopenia in the elderly in Shanghai. Methods 40 volunteers aged 20-77 years were enrolled and received BIA and dual-energy X-ray absorptiometry (DEXA) measurements in order to verify the reliability of BIA for measuring lean mass. 219 healthy young volunteers aged 20 to 40 years with ratio of gender men: women 100: 119 had BIA measurements to obtain peak muscle mass and sarcopenia diagnostic cut-off point of the elderly. 657 elderly aged ≥ 60 years with ratio of gendermen: women 318: 339 took BIA measurements to obtain the prevalence of sarcopenia in the elderly in Shanghai. Results No statistical difference between BIA-measured and DEXA-measured LM was observed (P=0.307). The appendicular skeletal muscle mass/height2 (ASM/h2) was (7.90±0.62) kg/m2 in young men, and (6.12±0.44) kg/m2 in young women, the cut off in elderly men and women were ≤6.66 kg/m2 and ≤ 5.24 kg/m2 respectively. Elderly people were divided into three age groups: aged60-69 years group, aged 70-69 years group, aged ≥ 80 years group, The prevalence of sarcopenia were 14.6%, 25.0% and 36.0% in men and 6.8%, 12.6% and 27.9% in women in aged 60-69 years, aged 70-69 years, aged ≥ 80 years groups, respectively. The overall prevalence in elderly men and women were 23.6% and 11.8% respectively. Conclusions Measurement of LM by BIA is validated in Shanghai volunteers. The prevalence of sarcopenia in the elderly is increased with age, which is higher in elderly men than in elderly women. Key words: Muscular diseases; Electric impedance; Body composition

A variety of easy-to-use commercial bioelectrical impedance appliances are available. The aim of this study was to examine the usefulness of a commercially available body composition meter using bioelectrical impedance analysis (BIA) by comparing its measurement results with those obtained from dual-energy X-ray absorptiometry (DXA). The participants were 443 children aged from 10 to 14 years (226 boys and 217 girls). Fat mass, fat-free mass, lean body mass, percentage of body fat, and bone mineral contents were evaluated for all participants using BIA and DXA. The agreement in the anthropometric data obtained from both devices was analyzed using correlation analysis, intraclass correlation coefficient (ICC), Lin’s concordance correlation coefficient (CCC), Bland–Altman plots, and ordinary least products regression analysis. Equivalence between both devices was tested by two one-sided t-test. All measured indicators showed strong linear correlations between the two measurement systems (r, 0.853–1.000). Fat mass, fat-free mass, and lean body mass showed absolute concordance (ICC, 0.902–0.972; Lin’s CCC, 0.902–0.972). BIA overestimated bone mineral content (62.7–66.5%) and underestimated percentage of body fat (− 8.9 to − 0.8%), lean body mass (− 3.5 to − 1.8%), and body mass (− 0.8 to − 0.5%). For fat mass and fat-free mass, the overestimate or underestimate varied according to the sex and statistical analysis test. Bland–Altman analysis and ordinary least products analysis showed fixed bias and proportional bias in all indicators. Results according to quartiles of body mass index showed poor agreement for fat mass and percentage of body fat in both boys and girls in the lowest body mass index quartile. The present results revealed strong linear correlations between BIA and DXA, which confirmed the validity of the present single-frequency BIA-derived parameters. Our results suggest that BIA cannot provide the exact same values as DXA for some body composition parameters, but that performance is sufficient for longitudinal use within an individual for daily health management and monitoring.

Introduction Limb muscle mass measurement using dual-energy X-ray absorptiometry (DXA) is considered the gold standard for the diagnosis of sarcopenia. Moreover, bioelectrical impedance analysis (BIA) is also recognized as a beneficial tool considering its high correlation with DXA. However, it remains to be elucidated whether DXA and BIA can accurately measure trunk lean mass. The aim of this study was to investigate the correlation between DXA and BIA measurements of trunk muscle mass and the cross-sectional area (CSA) of trunk muscles measured using magnetic resonance imaging (MRI) and to compare measures of trunk muscle mass obtained using DXA and BIA in patients with low back pain (LBP). Methods In total, 65 patients participated in the study. The correlation between DXA and BIA measurements and the CSA of trunk and paraspinal muscles at the L4-5 level were calculated. In addition, the correlation between DXA and BIA measurements of trunk muscle mass and the differences between these two measurements were determined. Results The correlation coefficient between DXA and BIA trunk muscle mass measurement and trunk muscle CSA was 0.74 and 0.56 for men and 0.69 and 0.44 for women, respectively. DXA and BIA measurement values showed a significantly moderate correlation with the CSA of the erector spinae (ES) and psoas major (PM). The multifidus (MF) CSA did not correlate with measurements of DXA and BIA in both men and women. Although DXA and BIA measurements were significantly correlated, a significant difference between these two measurements was found. BIA overestimated the trunk muscle mass significantly compared with DXA. Conclusions Trunk muscle mass measured with DXA and BIA was correlated with the CSA of most trunk muscles. Although the measurement of DXA and BIA showed a high correlation, BIA overestimated trunk muscle mass compared with DXA. Both DXA and BIA are beneficial for measuring trunk muscle mass.