Final answer:
Bioelectric Impedance Analysis (BIA) estimates body fat by passing a low electrical current through the body, measuring the resistance to current flow, which correlates with body fat content.
Step-by-step explanation:
Bioelectric Impedance Analysis (BIA) is a method used to estimate body fat content. This technique involves passing a low electrical current through the body to measure resistance to the flow of the current, which varies depending on the amount of body fat. Fat, being less conductive than muscle or water, slows down the passage of electricity, allowing the device to estimate the user's body composition. BIA is a convenient option compared to other methods like skinfold thickness measurements, waist circumference assessments, and Dual-energy X-ray absorptiometry (DEXA), and it is available for both professional use and home use as body composition scales.