Bodystat^® Phase Angle

The Bodystat^®1500 single frequency unit measures Impedance, the resistance to the flow of the current in the body. High fat levels result in high impedance values. Typically females carry higher fat levels than males and consequently reflect higher impedance values.

However, the Bodystat^®1500MDD dual-frequency and QuadScan 4000 multi-frequency devices, incorporate a Phase Angle measurement.

Impedance is made up of two bioelectrical parameters:
Resistance (R) and Reactance (Xc).

Resistance is the opposition offered by the body to the flow of an alternating electrical current and is inversely related to the water and electrolyte content of tissue.

Reactance is related to the capacitance properties of the cell membrane and variations can occur depending on its integrity, function, and composition.

The reactive component is assumed to be produced by the capacitive properties of cells that shift the voltage and current out of phase. In electrical terms, this phenomenon is defined by the Phase Angle (PA), where PA = arctangent (Xc/R).

Uniquely Bodystat®1500MDD & QuadScan 4000 units MEASURE directly PA from which is then derived R and Xc.

Direct Phase Angle Measurement

The Definition of Complex Impedance Phase Angle

Phase angle expresses both changes in the amount as well as the quality of soft tissue mass (i.e. cell membrane permeability and soft tissue hydration). Phase angle is dependent on:

• the capacitive behaviour of tissues (reactance) associated with cellularity, cell size and integrity of the cell membrane,

• its pure resistive behaviour (resistance), mainly dependent on tissue hydration.

Phase angle is significantly greater in men (who have more muscle mass) than in women in all age categories.

Although, its biological meaning and pathogenic effects are not completely understood, PA has been interpreted as an indicator of membrane integrity and water distribution between the intra- and extra-cellular spaces.

The phase angle can typically range between 2° and 12°.

A low phase angle is an indicator of cell membrane breakdown and an inability of cells to store energy.

A high phase angle indicates that the membranes of the cells are intact and body cell mass (BCM) is high.

Therefore the phase angle has been shown to provide a reliable prediction of the outcome of a variety of clinical conditions where alterations in cell membranes are known to have occurred e.g. HIV infection or cancer.

However, PA is not easy to explain nor easily understood. Therefore, Bodystat has introduced the unique concept of its Wellness and Illness Markers.