Originally Posted by braisler

I have a Tanita scale too. The body fat measurement is supposed to be based on conductance of your body's tissues. The scale sends a VERY mild electrical current through your body and uses that to calculate your body fat %. Don't worry, you can't feel the current. Now, I have a suspicion that the Tanita scale is actually measuring the conductance and factoring in your height and weight (You input those into the scale) to make a calculation of its estimate of your body fat. I don't know how accurate it is, because I have weighed myself and gotten one figure and then weighed myself while holding a large textbook (non-conductive, and not in the circuit) and my "body-fat" went up significantly.

I do like having the body-fat % there as it helps with my motivation, but I don't put too much faith in it being dead-on accurate. Interestingly, I am going to have a total body composition test done in the next couple of weeks, so I'll have an update as to how accurate my scale is then.