Figuring body fat with bioelectric impedance

Bioelectrical impedance analysis promises at least one measure of body composition that can be applied to large populations.

Bioelectrical impedance is inexpensive, easy to use, and free of observer bias. It evaluates the electricity conductivity characteristics of the human body.

Human body is full of fluids packed with electrolytes, such as sodium and potassium, ion that conduct the electrical impulses that send message back and forth among the cells.

Muscle tissue contains more fluid than fat tissue, so a body with more muscle than fat is less resistant to an outside electrical current.

Electricity is not conducted by fat because adipose tissue is less than 5% water whereas a lean tissue is a good conductor of electricity because it is mostly water.

To measure body resistant to electric current, the technical conducting the test places electrodes at the wrists and ankles and zaps a harmless low intensity electric current through.

Then, she calculates how resistant the tissues were to the current. The final number indicates how much body fat in the body is available.

Precise bioelectrical impedance, measures of electrical and biological parameters are unknown and vary from person to persons because of differences in body size, shape, electrolytes fluids distribution, or other aspects of the body’s composition.

Also this method is unreliable in patients with any excess of deficiency of fluid as is common in eating disorders.
Figuring body fat with bioelectric impedance