Bioelectrical Impedance Analysis

The BIAS (bioelectrical impedance analysis) technique constitutes the estimation formula based on three variables: height, body weight, and bioelectrical impedance.  

The bioelectrical impedance increases when the weight decreases (dehydration).  But when the weight increases due to excess intake of food and water, the bioelectrical impedance decreases.  

Therefore, the change in the bioelectrical impedance is inversely proportional to the change in the weight.