InBody in Studies

Now with more frequencies, and frequencies up to 3000 kHz, the InBody970 and the BWA2.0 devices provide not only more outputs, but greater precision. Life journal in a July 2022 publication evaluated the newest InBody devices compared to dual-energy X-ray absorptiometry (DEXA) in a cohort of 109 individuals. What they found was that high-frequency InBody devices showed a “high correlation with the DEXA results” for assessing appendicular lean mass (β ≥ 0.95), fat-free mass (R2 ≥ 0.95), and percent body fat (R2≥ 0.89). 

Yi, Y.; Baek, J.; Lee, E.; Jung, H.; Jang, I. (July 2022). “A Comparative Study of High-Frequency Bioelectrical Impedance Analysis and Dual-Energy X-ray Absorptiometry for Estimating Body Composition”. Life 2022, 12(7), 994; https://doi.org/10.3390/life12070994

The Journal of Pediatric Gastroenterology and Nutrition published a 2020 study that evaluated the accuracy of different BIA devices relative to DXA in children with obesity. Amongst other BIA, InBody stood out as it was “relatively accurate for estimating body fat percentage” and was not limited to patients younger than 10 or patients with high body fat percentage (>50%). Beyond being a “reasonably accurate alternative to DXA” in pediatric obesity, InBody is available at a tenth of the cost.

Khan, S., Xanthakos, S. A., Hornung, L., Arce-Clachar, C., Siegel, R., & Kalkwarf, H. J. (2020). Relative Accuracy of Bioelectrical Impedance Analysis for Assessing Body Composition in Children With Severe Obesity. Journal of Pediatric Gastroenterology & Nutrition, 70(6), e129–e135. https://doi.org/10.1097/MPG.0000000000002666 

Researchers from the Mayo Clinic compared InBody technology to DXA, a body composition gold standard, for estimating fat-free mass and percent body fat in a 2020 study. They validated InBody as 98% correlated to DXA and overall had good agreement amongst all BMI categories. The authors note that InBody “allows providers to further risk stratify patients and develop treatment plans.” On another note, InBody “takes the same amount of space as a scale and allows our clinical assistants to obtain body composition measurements in a few minutes while obtaining other vitals (eg, weight, heart rate, and blood pressure).”

Ryan T. Hurt; Jon O. Ebbert; Ivana Croghan; Sanjeev Nanda; Darrell R. Schroeder; Levi M. Teigen; Saketh R. Velapati; and Manpreet S. Mundi. The Comparison of Segmental Multifrequency Bioelectrical Impedance Analysis and Dual-Energy X-ray Absorptiometry for Estimating Fat Free Mass and Percentage Body Fat in an Ambulatory Population. Journal of Parenteral and Enteral Nutrition. 00.0, 1-8 (2020). 10.1002/jpen.1994

In a 2021 study published by Elsevier Ltd, the correlation of Multi-Frequency Bioelectrical Impedance Analysis (InBody720) was assessed in comparison to Computed Tomography (CT). The study found that body fat mass and body fat percentage measurements obtained by BIA showed excellent correlations with CT-based torso fat volume and waist fat area in both men and women, with correlation coefficients ranging from 0.86 to 0.95 (P < .001 for all).

Lee, Y.S., Hong, N., Witanto, J.N., Choi, Y.R., Park, J., Decazes, P., Eude, F., Kim, C.O., Kim, H.C., Goo, J.M. and Rhee, Y., 2021. Deep neural network for automatic volumetric segmentation of whole-body CT images for body composition assessment. Clinical Nutrition, 40(8), pp.5038-5046. https://doi.org/10.1016/j.clnu.2021.06.025.

A 2019 study from the Journal of Functional Morphology and Kinesiology compared InBody770 and DXA for body composition changes in exercise-trained men and women after a 4-week program. The researchers found that the device “can predict changes in body composition (i.e., fat mass, fat-free mass, and percent body fat) similar to a DXA.” InBody’s multiple frequencies “may be less subject to error” and “likely a superior method for the estimation of total body composition.”

Antonio, J.; Kenyon, M.; Ellerbroek, A.; Carson, C.; Burgess, V.; Tyler-Palmer, D.; Mike, J.; Roberts, J.; Angeli, G.; Peacock, C. Comparison of Dual-Energy X-ray Absorptiometry (DXA) Versus a Multi-Frequency Bioelectrical Impedance (InBody 770) Device for Body Composition Assessment after a 4-Week Hypoenergetic Diet. J. Funct. Morphol. Kinesiol. 2019, 4, 23. https://doi.org/10.3390/jfmk4020023 

Researchers in the American Journal of Clinical Nutrition assessed the integration of DXA and InBody for a rapid body composition model in a 2018 clinical population study. What they found was that InBody had “high agreement” with D20 TBW measurements, the gold standard for assessing body water. Nonetheless, InBody is “an appealing method for clinical TBW measurement owing to its low cost, rapid results, and amenability to field calibration.”

Ng, B. K., Liu, Y. E., Wang, W., Kelly, T. L., Wilson, K. E., Schoeller, D. A., Heymsfield, S. B., & Shepherd, J. A. (2018). Validation of rapid 4-component body composition assessment with the use of dual-energy X-ray absorptiometry and bioelectrical impedance analysis. American Journal of Clinical Nutrition, 108(4), 708–715. https://doi.org/10.1093/ajcn/nqy158

In a 2010 study published by the American College of Sports Medicine, the accuracy of the MF-BIA (InBody520) was assessed for measuring Fat-Free Mass (FFM). This evaluation compared MFBIA results with those from hydrostatic weighing (HW) and skinfold measurements (SK) in high school wrestlers. There was a strong correlation (r = 0.96) and no significant differences in mean Fat Free Mass (FFM) predicted by MFBIA when compared to hydrostatic weighing (HW). Furthermore, there were no significant differences in mean FFM values between the two methods, suggesting that MFBIA provides FFM measurements that are statistically comparable to those obtained through hydrostatic weighing.

Utter, A.C. and Lambeth, P.G., 2010. Evaluation of multifrequency bioelectrical impedance analysis in assessing body composition of wrestlers. Med Sci Sports Exerc, 42(2), pp.361-367. https://doi.org/10.1249/MSS.0b013e3181b2e8b4.

The Obesity Science & Practice published a 2019 study that validated the efficacy and reliability of Multi-Frequency Bioelectrical Impedance Analysis (MF-BIA) compared to Air Displacement Plethysmography (ADP). Strong correlations were observed between the Multi-Frequency Bioelectrical Impedance Analysis (MF-BIA) and Air Displacement Plethysmography (ADP) for various body composition metrics. For Percent Body Fat (%), the correlation coefficients ranged from 0.88 to 0.96 (P<0.001), while for Fat Mass (FM), the correlation was exceptionally high at 0.99 (P<0.001). Similarly, the correlation for Fat Free Mass (FFM) ranged from 0.93 to 0.97 (P<0.001). These strong relationships indicate that the InBody720 MF-BIA analyzer provides body composition measurements consistent with ADP, supporting its efficacy and reliability for use in the obese population.

Sullivan, P.A., Still, C.D., Jamieson, S.T., Dixon, C.B., Irving, B.A. and Andreacci, J.L., 2019. Evaluation of multi‐frequency bioelectrical impedance analysis for the assessment of body composition in individuals with obesity. Obesity science & practice, 5(2), pp.141-147. https://doi.org/10.1002/osp4.321