Total body electrical conductivity (TOBEC) analysis is a bioelectrical technique that uses measures total body electrical conductivity to estimate lean body mass. Other dimensions can also be assessed. The method was originally developed to quantify lean tissue in meat.
The TOBEC method is based on the principle that organisms placed in an electro-magnetic field perturb the field. The degree of perturbation is dependent on the amount and volume of distribution of electrolytes present. Fat free mass (FFM) has a much higher water and electrolyte content than fat mass (FM) and the strength of the field depends on the electrolytes found in the person's body water.
This method is most accurate when measuring lean mass. However, it is not widely available and expensive to purchase.
TOBEC has been used mainly to monitor changes in body composition in women during pregnancy or lactation, in infants and in childhood obesity.
An overview of the characteristics of TOBEC is outlined in Table 1.
Table 1 Characteristics of TOBEC.
|Number of participants||Small|
|Researcher burden of data collection||Low|
|Researcher burden of coding and data analysis||Low|
|Risk of reactivity bias||No|
|Risk of recall bias||No|
|Risk of social desirability bias||No|
|Risk of observer bias||Yes|
|Suitability for field use||Not suitable|
|Participant literacy required||No|
Considerations relating to the use of TOBEC in specific populations are described in Table 2.
Table 2 Use of TOBEC in different populations.
|Infancy and lactation||Yes*|
|Toddlers and young children||Yes*|
*TOBEC has been used mainly to monitor changes in body composition in women during pregnancy or lactation, in infants and in childhood obesity.
Refer to section: practical considerations for objective anthropometry