Phase Angle Measurement in Healthy Human Subjects through Bio-Impedance Analysis

Document Type : Original Article


1 Department of Physiology, Yenepoya Medical College, Deralakatte, Mangalore-575018. Karnataka, India

2 Department of Radiology, Yenepoya Medical College, Deralakatte, Mangalore-575018. Karnataka, India


Bioelectrical impedance is the measure of impedance of the body. Impedance consists of electric resistance and reactance. Phase angle (PA) is the tan value of the ratio of reactance versus electric resistance. PA depends on cell membrane integrity and on body cell mass. There exists a correlation between PA values and body cell mass.
The objective of this study was to compare the PA values of normal individuals and their anthropometric measurements.
Materials and Methods
Anthropometric measurements, Bioelectrical impedance analysis and PA measurements were done using Bodystat Quadscan 4000 machine on 42 healthy subjects between the age group of 18 to 50 yrs at a private hospital, Bangalore, Karnataka, India for eight months. Kolmogrov-Smirnov and Pearson’s correlation tests were used for data analysis.
The PA values were 7.321.17º in healthy subjects. PA values were significantly positively correlated with body mass index (BMI) (r= 0.011, P<0.001). The phase angle values for males and females were 7.43±0.98º and 7.05±1.1.58º, respectively.
PA values positively correlated with BMI indicating the nutritional status of the study group. PA values were similar to the values to found in other studies.


1. Kushner RF. Bioelectrical impedance analysis: A review of principles and applications. J Am Coll Nutr 1992; 11:199–209.
2. Foster KR, Lukaski HC. Whole body impedance- what does it measure? Am J Clin Nutr 1996; 64:388-396.
3. Cowen S, Hannan WJ, Ghosh S. Nutrition index determined by a portable multifrequency bioelectrical impedance analysis machine. GUT 1998; 42:144-152.
4. Schwenk A, Beisenherz A, Romer K, Kremer G, Salzberger B, Elia M. Phase angle from bioelectrical impedance analysis remains an independent predictive marker in HIV infected patients in the era of highly active antiretroviral treatment. Am J Clin Nutr 2000; 72:496-501.
5. Gupta D, Lammersfeld CA, Burrows JL, Dahlk SL,Vashi PG, Grutsch JF, et al. Bioelectrical impedance phase angle in clinical practice: implications for prognosis in advanced colorectal cancer. Am J Clin Nutr 2004; 80:1634-1638.
6. Guglielmi FW, Mastronuzzi T, Pietrini L, Panarese A, Panella C, Francavilla A. Electrical bioimpedance methods: applications to medicine and biotechnology. Ann N Y Acad Sci 1999; 873:105-111.
7. Schloerb PR, Forster J, Delcore R, Kindscher JD. Bioelectrical impedance in the clinical evaluation of liver disease. Am J Clin Nutr 1996; 64:510-14.
8. Savastano S, Belfiore A, Di Somma C, Mauriello C, Rossi A, Pizza G, et al. Validity of bioelectrical impedance analysis to estimate body composition changes after bariatric surgery in premenopausal morbidly women. Obes Surg 2010; 20:332-339.
9. Lukaski HC. Biological indexes considered in the derivation of the bioelectrical impedance analysis. Am J Clin Nutr 1996; 64:397-404.
10. Guo SS, Chumlea WC, Cockram DB. Use of statistical methods to estimate body composition. Am J Clin Nutr 1996; 64:428-435.
11. Gupta D, Lis CG, Dahlk SL, Vashi PG, Grutsch JF, Lammersfeld CA. Bioelectrical impedance phase angle as a prognostic indicator in advanced pancreatic cancer. Br J Nutr 2004; 92:957-962.
12. Van lettow M, Kumwenda JJ, Harries AD, Whalen CC, Taha TE, Kumwenda N, et al. Malnutrition and the severity of lung disease in adults and pulmonary tuberculosis in Malawi. Int J Tuberc Lung Dis 2004; 8:211-217.
13. Cristina MG, Silva B, Aluisio JD, Barros AJD, Wang J, Heymsfield SB, et al. Bioelectrical impedance analysis: Population reference values for phase angle by age and Sex. Am J Clin Nutr 2005; 82:49-52.
14. Fuller NJ, Elia M. Potential use of bioelectrical impedance of the whole body and of body segments for the assessment of body composition: comparison with densitometry and anthropometry. Eur J Clin Nutr 1989; 43:779-791.
15. Norman K, Stobäus N, Pirlich M, Bosy-Westphal A. Bioelectrical phase angle and impedance vector analysis - Clinical relevance and applicability of impedance parameters. Clin Nutr 2012 Jun 12. [Epub ahead of print]
16. Walter-Kroker A, Kroker A, Mattiucci-Guehlke M, Glaab T. A practical guide to bioelectrical impedance analysis using the example of chronic obstructive pulmonary disease. Nutr J 2011; 10:35.
17. Stobäus N, Pirlich M, Valentini L, Schulzke JD, Norman K. Determinants of bioelectrical phase angle in disease. Br J Nutr 2012; 107:1217-1220.
18. Kushner RF, Schoelle DA, Gudivaka R. Clinical characteristics influencing bioelectrical impedance analysis measurements. Am J Clin Nutr 1996; 64:423-427.
19. Steiner MC, Barton RL, Singh SJ, Morgan MDL. Bedside methods versus dual energy X-ray absorptiometry for body composition measurement in COPD. Eur Respir J 2002; 19:626-631.
20. Leitgeb N, Schrottner J, Cech R. Perception of ELF electromagnetic fields: excitation thresholds and inter-individual variability. Health Phys 2007; 92:591-595.
21. Lindenblatt G, Silney J. Evaluation and comparison of 50 Hz current threshold of electrocutaneous sensations using different methods. Science 2006; 7:933-946.